Influenza Situation Updates 2016

Bi-weekly Influenza Situation Update 20 December 2016 Virological Surveillance Summary The number of specimens reported to FluNet by the Western Pacific Region countries and areas between week 1 and week 49, and the number of Influenza positive specimens are presented in the table below. Influenza A (H3) is currently the predominant circulating subtype (Figure 1). Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 49, 2016 Figure 1: Number of influenza positive specimens by subtype and week, Western Pacific Region, 2015-16 (accessed 20 December 2016) Country (most recent week) Total number of specimens processed Total number of influenza positive specimens Australia (week 49) 36,411 6,190 Cambodia (week 48) 1,334 356 China (week 49) 524,461 77,504 Fiji (week 38) 349 120 Japan (week 48) NA 7,231 Lao People's Democratic Republic (week 42) 4,495 403 Malaysia (week 30) 2,461 212 Mongolia (week 49) 3,783 364 New Caledonia (week 41) 1,360 301 New Zealand (week 39) 942 298 Papua New Guinea (week 39) 388 143 Philippines (week 48) 1027 251 Republic of Korea (week 49) 10,329 1,371 Singapore (week 49) 2,254 1,149 Viet Nam (week 47) 1,421 333 Influenza Situation Update| 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection (ARI) with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In Republic of Korea, the proportion of ILI visits per 1,000 patients increased sharply between epidemiological weeks 48 and 50. In the most of the other countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity is increasing and following seasonal trends. Outpatient ILI Surveillance China (North) During week 47, the percentage of visits for ILI at national sentinel hospitals in northern China was 3.4%, which was higher than the previous week and the same week of 2014 and 2015 (Figure 2). Mongolia There has been a increase in ILI activity in Mongolia since week 30, which follows seasonal trends (Figure 3). Republic of Korea In week 50 2016, the proportion of ILI visits per 1,000 patients was 34.8 ILI cases per 1,000 patients, which increased sharply from 13.3 ILI cases per 1,000 patients recorded in the previous week. (Figure 4). Source: http://www.cdc.go.kr/CDC/eng/info/CdcEngInfo0101.jsp?menuIds=HOME002- MNU0826-MNU0825 China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatient ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update| 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 30 November 2016, influenza activity is increasing and following seasonal trends (Figure 5). Figure 5: Number of influenza cases reported weekly per reporting sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update| 4 Countries/areas in the tropical zone In weeks 1 to 49 of 2016, ILI or ARI activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance In week 50, the average consultation rate for ILI among sentinel general outpatient clinics (GOPCs) was 4.0 ILI cases per 1,000 consultations, which was lower than the rate of 4.2 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 50.8 ILI cases per 1,000 consultations, which was higher than the rate of 47.1 recorded in the previous week (Figure 7). Among the respiratory specimens received in week 50,200(5.47%) tested positive for seasonal influenza viruses, which was lower than 6.34% recorded in the previous week. Influenza A(H3) was the predominant subtype detected comprising 96.5% of respiratory specimens. Other viruses detected were influenza C (2.0%), influenza A(H1)(1.0%), and influenza B(0.5%). China (South) - ILI Surveillance During week 47, the percentage of outpatient or emergency visits for ILI (ILI %) at national sentinel hospitals in southern China was 3.1%, which ws the same as the previous week (3.1%), and higher than the same week of 2014 and 2015 (2.2% and 2.6%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI decreased from 2,589 (over 5.5 working days) in week 48 to 2,377 (over 5.5 working days) in week 49 (Figure 9). The proportion of patients with ILI among polyclinic attendances for ARI remained low at 1.0%. The overall positivity rate for influenza virus among ILI samples (n=62) in the community was 35.5% in the past 4 weeks. Of influenza-positive specimens in November 2016, the majority were influenza A(H3N2) (64.3%), followed by influenza A(H1N1)pdm09 (3.6%) and influenza B (32.1%). Source: https://www.moh.gov.sg/content/dam/moh_web/Statistics/Infectious_Diseases_Bulletin/2016/Decemb er/2016_week_49.pdf Influenza Situation Update| 5 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for ARI, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza Situation Update| 6 Countries in the temperate zone of the southern hemisphere In the temperate zone of the southern hemisphere, influenza activity followed seasonal trends. Australia – Laboratory-confirmed influenza(no update) As of 28 October 2016, a total of 83,092 notifications of laboratory confirmed influenza were reported to the National Notifiable Diseases Surveillance System (Figure 10). Ninety percent of notifications were influenza A (73% A (unsubtyped), 6% influenza A(H1N1)pdm09 and 11% influenza A(H3N2), 10% were influenza B and less than 1% were influenza C, influenza A&B co-infections or untyped. Source: http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu- flucurr.htm/$File/Australian-Influenza-Surveillance-Report.pdf Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness (no update) In week 39, ending 2 October 2016, 24 patients with ILI consulted sentinel general practices in 20 District Health Boards. The weekly ILI incidence was 4.4 ILI cases per 100 000 patients. Of the 14 tested ILI cases, 4 were positive for influenza viruses, yielding an influenza-associated ILI incidence rate of 1.3 ILI cases per 100 000 patients (adjusted) . Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Influenza Situation Update| 7 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 49, the number of ILI cases reported was higher than the previous week in American Samoa and Vanuatu. The number of ILI cases in Solomon Islands, Fiji and Tonga decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Influenza Situation Update| 8 Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 6 December 2016 Virological Surveillance Summary The number of specimens reported to FluNet by the Western Pacific Region countries and areas between week 1 and week 47, and the number of Influenza positive specimens are presented in the table below. Influenza A (H3) is reported to be the predominantly circulating subtype currently (Figure 1). Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 47, 2016 Figure 1: Number of influenza positive specimens by subtype and week, Western Pacific Region, 2015-16 (accessed 5 December 2016) Country (most recent week) Total number of specimens processed Total number of influenza positive specimens Australia (week 47) 35,572 6,166 Cambodia (week 45) 1,254 343 China (week 47) 506,169 74,614 Fiji (week 38) 349 120 Japan (week 46) NA 7,190 Lao People's Democratic Republic (week 42) 4,495 403 Malaysia (week 30) 2,461 212 Mongolia (week 47) 3,336 335 New Caledonia (week 41) 1,360 301 New Zealand (week 39) 942 298 Papua New Guinea (week 39) 388 143 Philippines (week 47) 999 250 Republic of Korea (week 47) 9,870 1,298 Singapore (week 47) 2,231 1,141 Viet Nam (week 43) 1,219 326 Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection (ARI) with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 47 ILI% at national sentinel hospitals in north China was 3.4%, higher than last week and the same week of 2014 and 2015 (Figure 2). Mongolia There has been a increase in ILI activity in Mongolia since week 30, which follows seasonal trends (Figure 3). Republic of Korea In week 47 2016, overall weekly ILI) rate was 5.9‰, which is higher than 4.5 recorded in the previous week (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatient ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 16 November 2016, influenza activity is increasing and following seasonal trends (Figure 5). Figure 5: Number of influenza cases reported weekly per reporting sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 47 of 2016, ILI or ARI activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance In week 48, the average consultation rate for ILI among sentinel general outpatient clinics (GOPCs) was 4.4 ILI cases per 1,000 consultations, which was similar to 4.3 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 46.4 ILI cases per 1,000 consultations, which was lower than 54.8 recorded in the previous week(Figure 7). Among the respiratory specimens received in week 48,231 (6.67%) were tested positive for seasonal influenza viruses, including 1 (0.03%) influenza A(H1), 223 (6.44%) influenza A(H3), 1 (0.03%) influenza B and 6 (0.17%) influenza C. The percentage of respiratory specimens tested positive for seasonal influenza viruses last week was 6.67%, which was lower than 7.08% recorded in the previous week. Among the influenza viruses detected in the last week, the proportions of A(H3), C, A(H1) and B were 96.5%, 2.6%, 0.4% and 0.4% respectively. China (South) - ILI Surveillance During week 47, the percentage of outpatient or emergency visits for ILI (ILI %) at national sentinel hospitals in south China was 3.1%, same as last week (3.1%), higher than the same week of 2014 and 2015 (2.2% and 2.6%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI decreased from 2,651 (over 5.5 working days) in week 46 to 2,620 (over 5.5working days) in week 47(Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 1.2%. The overall positivity rate for influenza among ILI samples (n=69) in the community was 40.6% in the past 4 weeks. Of the specimens tested positive for influenza in October 2016, these were positive for influenza A(H3N2) (84.6%), influenza A(H1N1)pdm09 (7.7%) and influenza B (7.7%). Source: https://www.moh.gov.sg/content/dam/moh_web/Statistics/Infectious_Diseases_Bulletin/2016/November/2016_ week_47.pdf Influenza Situation Update | 5 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for ARI, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza Situation Update | 6 Countries in the temperate zone of the southern hemisphere In the temperate zone of the southern hemisphere, influenza activity followed seasonal trends, declining in Australia and remaining at low levels in New Zealand. Australia – Laboratory-confirmed influenza(no update) As of 28 October 2016, a total of 83,092 notifications of laboratory confirmed influenza were reported to the National Notifiable Diseases Surveillance System (Figure 10). Ninety percent of notifications were influenza A (73% A (unsubtyped), 6% influenza A(H1N1)pdm09 and 11% influenza A(H3N2), 10% were influenza B and less than 1% were influenza C, influenza A&B co-infections or untyped. Source: http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu- flucurr.htm/$File/Australian-Influenza-Surveillance-Report.pdf Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness (no update) In week 39, ending 2 October 2016, 24 patients with ILI consulted sentinel general practices in 20 District Health Boards. The weekly ILI incidence was 4.4 ILI cases per 100 000 patients. Of the 14 tested ILI cases, 4 were positive for influenza viruses, yielding an influenza-associated ILI incidence of of 1.3 per 100 000 patients (adjusted). Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Influenza Situation Update | 7 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 47, the number of ILI cases reported was higher than the previous week in American Samoa. The number of ILI cases in Guam, Tokelau and Tonga decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance /en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Influenza Situation Update | 8 Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 22 November 2016 Virological Surveillance Summary The number of specimens reported to FluNet by the Western Pacific Region countries and areas between week 1 and week 45, and the number of Influenza positive specimens are presented in the table below. Influenza A (H3) is reported to be the predominantly circulating subtype currently (Figure 1). Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 45, 2016 Figure 1: Number of influenza positive specimens by subtype and week, Western Pacific Region, 2015-16 (accessed 8 November 2016) Country (most recent week) Total number of specimens processed Total number of influenza positive specimens Australia (week 45) 35,063 6,139 Cambodia (week 43) 1,189 331 China (week 45) 488,624 72,402 Fiji (week 38) 349 120 Japan (week 42) NA 7,093 Lao People's Democratic Republic (week 42) 4,495 403 Malaysia (week 30) 2,461 212 Mongolia (week 41) 2,933 335 New Caledonia (week 41) 1,360 301 New Zealand (week 39) 942 298 Papua New Guinea (week 39) 388 143 Philippines (week 45) 963 248 Republic of Korea (week 44) 9,005 1,292 Singapore (week 44) 2,179 1,122 Viet Nam (week 43) 1,219 326 Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection (ARI) with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 45, the percentage of consultations for ILI at national sentinel hospitals in Northern China was 3.1%. This is higher than the previous week of 2016 (2.8%) and same as the same week of 2015 (2.5%) (Figure 2). Mongolia There has been a increase in ILI activity in Mongolia since week 30, which follows seasonal trends (Figure 3). Republic of Korea In week 44, the overall weekly ILI rate was 4.8 ILI cases/1,000 outpatients, which is the same as the previous week and the national baseline of 8.9 ILI cases/1,000 outpatients (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatient ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 9 November 2016, influenza activity is low and following seasonal trends (Figure 5). Figure 5: Number of influenza cases reported weekly per reporting sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 44 of 2016, ILI or ARI activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance As of week 44, the average consultation rate for ILI among sentinel general outpatient clinics was 4.8 ILI cases per 1,000 consultations, which was lower than the 5.7 ILI cases per 1,000 consultations recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 47.8 ILI cases per 1,000 consultations, which was similar to the 47.7 ILI cases per 1,000 consultations recorded in the previous week (Figure 7). These average consultation rates for ILI among sentinel general outpatient clinics and private doctors are the highest observed in 5 years. The percentage of respiratory specimens in week 46 which tested positive for seasonal influenza viruses was 8.06%. This is lower than the 8.95% recorded in the previous week. Influenza A(H3) was the predominant circulating subtype comprising 98.2% of positive respiratory specimens. Other viruses detected were influenza B (1.1%), influenza C (0.4%) and influenza A(H1) (0.4%). China (South) - ILI Surveillance During week 45, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in southern China was 3.0%. This is higher than that in the previous week of 2016 (2.8%) and higher than that in the same week of 2015 (2.2%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI was 2,462 (over 5.5 working days) in week 45, decreased from previous week of 2,598 in week 44 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 1.0%. The overall influenza virus positivity of ILI samples (n=51) in the community was 31.4% in the past 4 weeks. Of the specimens tested positive for influenza virus in September 2016, 86.7% were positive for influenza A(H3N2), 6.7% for influenza B and 6.7% for influenza A(H1N1)pdm09. Source: https://www.moh.gov.sg/content/moh_web/home/statistics/infectiousDiseasesStatistics/weekly_infect iousdiseasesbulletin.html Influenza Situation Update | 5 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for ARI, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza Situation Update | 6 Countries in the temperate zone of the southern hemisphere In the temperate zone of the southern hemisphere, influenza activity followed seasonal trends, declining in Australia and remaining at low levels in New Zealand. Australia – Laboratory-confirmed influenza As of 28 October 2016, a total of 83,092 notifications of laboratory confirmed influenza were reported to the National Notifiable Diseases Surveillance System (Figure 10). Ninety percent of notifications were influenza A (73% A(unsubtyped), 6% influenza A(H1N1)pdm09 and 11% influenza A (H3N2), 10% were influenza B and less than 1% were influenza C, influenza A&B co-infections or untyped. Source: http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu- flucurr.htm/$File/Australian-Influenza-Surveillance-Report.pdf Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness (no update) In week 39, ending 2 October 2016, 24 patients with ILI consulted sentinel general practices in 20 District Health Boards. The weekly ILI incidence was 4.4 ILI cases per 100 000 patients. Of the 14 tested ILI cases, 4 were positive for influenza viruses, yielding an influenza-associated ILI incidence of of 1.3 per 100 000 patients (adjusted) . Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Influenza Situation Update | 7 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 45, the number of ILI cases reported was higher than the previous week in American Samoa, Solomon Islands and Fiji. The number of ILI cases in Vanuatu, Tonga and Federated States of Micronesia decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Influenza Situation Update | 8 Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Virological Surveillance Summary The number of specimens reported to FluNet by the Western Pacific Region countries and areas between week 1 and week 43, and the number of Influenza posiHve specimens are presented in the table below. Influenza A (H3) is reported to be the predominantly circulaHng subtype currently (Figure 1). Table 1: Countries and areas reporHng data to FluNet, Western Pacific Region, weeks 1 to 43, 2016 Country (most recent week) Total number of specimens processed Total number of influenza posiHve specimens Australia (week 43) 33,815 6,067 Cambodia (week 41) 1,121 316 China (week 42) 457,877 69,483 Fiji (week 38) 349 120 Japan (week 42) NA 7,093 Lao People's Democratic Republic (week 42) 4,495 403 Malaysia (week 30) 2,461 212 Mongolia (week 41) 2,871 335 New Caledonia (week 41) 1,360 301 New Zealand (week 39) 942 298 Papua New Guinea (week 39) 388 143 Philippines (week 43) 953 248 Republic of Korea (week 42) 8,622 1,291 Singapore (week 43) 2,161 1,114 Viet Nam (week 39) 1,025 308 Influenza SituaHon Update | 1 Bi-weekly Influenza SituaHon Update 8 November 2016 Figure 1: Number of influenza posiHve specimens by subtype and week, Western Pacific Region
 2015-16 (accessed 8 November 2016) Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpaHent and inpaHent senHnel surveillance systems. Case definiHons, populaHons under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where rouHne surveillance is conducted and informaHon is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory InfecHons (SARI). The WHO surveillance case definiHon for ILI is an acute respiratory infecHon with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infecHon (ARI) with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalizaHon. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza acHvity remained at low levels. OutpaHent ILI Surveillance China (North) 
 During week 43, the percentage of ILI visits at naHonal senHnel hospitals in Northern China was 2.7%. This is higher than the previous week of 2016 (2.6%) and same as the same week of 2015 (2.4%) 
 (Figure 2). Mongolia There has been a increase in ILI acHvity in Mongolia since week 30, which follows the seasonal trends (Figure 3). Influenza SituaHon Update | 2 Republic of Korea In week 44, overall weekly ILI rate was 4.8/1,000 outpaHents, which is the same as the previous week and the naHonal baseline of 8.9/1,000 outpaHents (Figure 4). Figure 4: Weekly proporHon of ILI visits per 1,000 paHents 2012-2016 
 (Source: Korean Centre for Disease Control and PrevenHon) Republic of Korea China (North) Figure 2: Percentage of visits for ILI at senHnel hospitals, 2012-2016 (Source: China NaHonal Influenza Center) Mongolia Figure 3: ProporHon of outpaHent ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia NaHonal Influenza Center) Influenza SituaHon Update | 3 SenHnel influenza surveillance Japan As of 26 October 2016, influenza acHvity is low and following seasonal trends (Figure 5). Figure 5: Number of influenza cases reported weekly per reporHng senHnel hospital site, Japan 2006-2016 (Source: Japan NaHonal InsHtute of InfecHous Diseases) Countries/areas in the tropical zone In weeks 1 to 44 of 2016, ILI or ARI acHvity followed previous seasonal trends in countries/areas in the tropical zone. OutpaHent Surveillance Hong Kong (China) - ILI Surveillance As of week 44, the average consultaHon rate for ILI among senHnel general outpaHent clinics was 4.7 ILI cases per 1,000 consultaHons, which was higher than 4.0 ILI cases per 1,000 consultaHons recorded in the previous week (Figure 6). The average consultaHon rate for ILI among senHnel private doctors was 48.6 ILI cases per 1,000 consultaHons, which was lower than 47.4 ILI cases per 1,000 consultaHons recorded in the previous week (Figure 7). The average consultaHon rates for ILI among senHnel general outpaHent clinics and private doctors were the highest in the previous 5 years. The percentage of respiratory specimens in week 44 which tested posiHve for seasonal influenza viruses was 8.68%. This is lower than 8.98% recorded in the previous week. Influenza A(H3) was the predominant circulaHng subtype comprising 97.3% of posiHve respiratory specimens. Other viruses detected were influenza B (1.4%), influenza C (0.7%) and influenza A(H1) (0.7%) Influenza SituaHon Update | 4 China (South) - ILI Surveillance During week 43, the percentage of outpaHent or emergency visits for ILI at naHonal senHnel hospitals in southern China was 2.8%. This is higher than that in the previous week of 2016 (2.7%) and higher than that in the same week of 2015 (2.3%) (Figure 8). Singapore – ARI Surveillance The average daily number of paHents seeking treatment in the polyclinics for ARI was 2,408 (over 5.5 working days) in week 43, decreased from previous week of 2,398 in week 42 (Figure 9). The proporHon of paHents with ILI among the polyclinic ahendances for ARI remained low at 1.5%. The overall influenza virus posiHvity of ILI samples (n=50) in the community was 22.0% in the past 4 weeks. Of the specimens tested posiHve for influenza virus in September 2016, 81.8% were posiHve for influenza A(H3N2), 9.1% for influenza B and 9.1% for influenza A(H1N1)pdm09. Source: hhps://www.moh.gov.sg/content/moh_web/home/staHsHcs/infecHousDiseasesStaHsHcs/ weekly_infecHousdiseasesbulleHn.html Hong Kong (China) - ILI Surveillance Figure 6: ILI consultaHon rates at senHnel general outpaHent clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health ProtecHon) Figure 7: ILI consultaHon rates at senHnel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health ProtecHon) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at naHonal senHnel hospitals in South China, 2012-2016 (Source: China NaHonal Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic ahendances for ARI, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza SituaHon Update | 5 Countries in the temperate zone of the southern hemisphere In the temperate zone of the southern hemisphere, influenza acHvity followed seasonal trends, declining in Australia and remaining at low levels in New Zealand. Australia – Laboratory-confirmed influenza As of 14 October 2016, a total of 79,534 noHficaHons of laboratory confirmed influenza were reported to the NaHonal NoHfiable Diseases Surveillance System (Figure 10). Ninety percent of noHficaHons were influenza A (72% A(unsubtyped), 7% influenza A(H1N1)pdm09 and 11% influenza A (H3N2), 10% were influenza B and less than 1% were influenza C, influenza A&B co-infecHons or untyped. Source: hhp:// www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu-flucurr.htm/$File/Australian- Influenza-Surveillance-Report.pdf Figure 10: Australian noHficaHons of laboratory confirmed influenza 
 (Source: NaHonal NoHfiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness (no update) In week 39, ending 2 October 2016, 24 paHents with ILI consulted senHnel general pracHces in 20 District Health Boards. The weekly ILI incidence was 4.4 per 100 000 paHent populaHon. Of the 14 tested ILI cases, 4 were posiHve for influenza viruses. This gives an ILI related influenza incidence (adjusted) of 1.3 per 100 000 paHent populaHon. 
 Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: InsHtute of Environmental Science and Research Ltd (ESR), New Zealand)
 Influenza SituaHon Update | 6 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 43, the number of ILI cases reported in Federated States pf Micronesia, Guam and Takelau shows above the threshold of 90% historical values (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situaHon updates Epidemiological update:hhp://www.who.int/influenza/surveillance_monitoring/updates/ latest_update_GIP_surveillance/en/ Virological update: hhp://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: hhp://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composiHon of influenza virus vaccines for use in the 2016 southern hemisphere influenza season hhp://www.who.int/influenza/vaccines/virus/recommendaHons/2016_south/en/ Influenza SituaHon Update | 7 AnHgenic and geneHc characterisHcs of zoonoHc influenza viruses and candidate vaccine viruses developed for potenHal use in human vaccines hhp://www.who.int/influenza/vaccines/virus/characterisHcs_virus_vaccines/en/ 4th WHO Informal ConsultaHon on Improving Influenza Vaccine Virus SelecHon 
 hhp://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selecHon/en/ Video on influenza on WHO's YouTube Channel Arabic: hhps://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: hhps://www.youtube.com/watch?v=xW9gDKEPitQ English: hhps://www.youtube.com/watch?v=yhhJfT86Bgg French: hhps://www.youtube.com/watch?v=8mo8rWWJZkc Russian: hhps://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: hhps://www.youtube.com/watch?v=qXr75cKxwTY Influenza SituaHon Update | 8

Bi-weekly Influenza Situation Update 17 June 2014 Virological Surveillance Summary The number of specimens reported to FluNet by the Western Pacific Region countries and areas between week 1 and week 39, and the number of Influenza positive specimens are presented in the table below. Influenza A (H3) is reported to be the predominantly circulating subtype currently (Figure 1). Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 39, 2016 Figure 1: Number of influenza positive specimens by subtype and week, Western Pacific Region, 2015-16 (accessed 11 October 2016) Country (most recent week) Total number of specimens processed Total number of influenza positive specimens Australia (week 39) 32,115 5,688 Cambodia (week 39) 1,053 293 China (week 38) 417,401 66,894 Fiji (week 38) 349 120 Japan (week 38) NA 7,072 Lao People's Democratic Republic (week 38) 3,784 226 Malaysia (week 30) 2,461 212 Mongolia (week 38) 2,802 335 New Caledonia (week 38) 1,320 301 New Zealand (week 34) 733 209 Papua New Guinea (week 39) 388 143 Philippines (week 38) 830 238 Republic of Korea (week 38) 7,907 1,288 Singapore (week 39) 2,092 1,106 Viet Nam (week 32) 771 274 Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection (ARI) with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 38, the percentage of ILI visits at national sentinel hospitals in Northern China was 2.4%. This is lower than the previous week of 2016 (2.7%) and higher than the same week of 2015 (2.3%) (Figure 2). Mongolia There has been a increase in ILI activity in Mongolia since week 30 until week 38 (Figure 3). Republic of Korea In week 40, overall weekly ILI rate was 4.2/1,000 outpatients, which is higher than 3.9 recorded in the previous week. The national baseline is 11.3/1,000 outpatients (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatient ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 28 September 2016, influenza activity is low and following seasonal trends (Figure 5). Figure 5: Number of influenza cases reported weekly per reporting sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 40 of 2016, ILI or ARI activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance As of week 40, the average consultation rate for ILI among sentinel general outpatient clinics was 4.7 ILI cases per 1,000 consultations, which was lower than 5.6 ILI cases per 1,000 consultations recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 56.2 ILI cases per 1,000 consultations, which was higher than 53.3 ILI cases per 1,000 consultations recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 40 which tested positive for seasonal influenza viruses was 12.4%. This is lower than 14.2% recorded in the previous week. Influenza A (H3) was the predominant circulating subtype comprising 98.8% of positive respiratory specimens. Other viruses detected were influenza B (1.0%) and influenza A (H1) (0.2%). China (South) - ILI Surveillance During week 38, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in southern China was 2.8%. This is lower than the previous week of 2016 (2.9%) and higher than the same week of 2015 (2.7%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI was 2,384 (over 5.5 working days) in week 39, decreased from previous week of 2,449 in week 38 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 1.3%. The overall influenza virus positivity of ILI samples (n=103) in the community was 31.1% in the past 4 weeks. Of the specimens tested positive for influenza virus in August 2016, 85.0% were positive for influenza A(H3N2), 13.1% for influenza B and 1.9% for influenza A(H1N1)pdm09. Source: https://www.moh.gov.sg/content/moh_web/home/statistics/infectiousDiseasesStatistics/weekly_infecti ousdiseasesbulletin.html). Influenza Situation Update | 5 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for ARI, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza Situation Update | 6 Countries in the temperate zone of the southern hemisphere In the temperate zone of the southern hemisphere, influenza activity followed seasonal trends, declining in Australia and remaining at low levels in New Zealand. Australia – Laboratory-confirmed influenza (no update) As of 16 September 2016, a total of 66,648 notifications of laboratory confirmed influenza were reported to the National Notifiable Diseases Surveillance System (Figure 10). Ninety percent of notifications were influenza A (71% A(unsubtyped), 7% influenza A(H1N1)pdm09 and 11% influenza A (H3N2), 10% were influenza B and less than 1% were influenza C, influenza A&B co-infections or untyped. Source:http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu- flucurr.htm/$File/Australian-Influenza-Surveillance-Report.pdf Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness In week 39, ending 2 Octomber 2016, 24 patients with ILI consulted sentinel general practices in 20 District Health Boards. The weekly ILI incidence was 4.4 per 100 000 patient population. Of the 14 tested ILI cases, 4 were positive for influenza viruses. This gives an ILI related influenza incidence (adjusted) of 1.3 per 100 000 patient population. Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Influenza Situation Update | 7 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 39, the number of ILI cases reported in Guam, Solomon Islands, Tokelau, Tonga and Vanuatu were reported above the threshold of 90% historical value (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Influenza Situation Update | 8 Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 27 September 2016 Virological Surveillance Summary The number of specimens reported to FluNet by the Western Pacific Region countries and areas between week 1 and week 37, and the number of Influenza positive specimens are presented in the table below. Influenza A (H3) is reported to be the predominantly circulating subtype currently (Figure 1). Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 37, 2016 Figure 1: Number of influenza positive specimens by subtype and week, Western Pacific Region, 2015-16 (accessed 27 September 2016) Country (most recent week) Total number of specimens processed Total number of influenza positive specimens Australia (week 37) 27,412 4,721 Cambodia (week 36) 966 256 China (week 37) 410,140 65,860 Fiji (week 35) 349 120 Japan (week 31) NA 7,000 Lao People's Democratic Republic (week 35) 3,564 195 Malaysia (week 30) 2,461 212 Mongolia (week 35) 2,768 335 New Caledonia (week 35) 1,238 298 New Zealand (week 34) 733 209 Papua New Guinea (week 35) 377 143 Philippines (week 35) 790 221 Republic of Korea (week 36) 7,571 1,287 Singapore (week 36) 2,002 1,082 Viet Nam (week 35) 771 274 Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection (ARI) with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 37, the percentage of ILI visits at national sentinel hospitals in Northern China was 2.7%. This is higher than the previous week of 2016 (2.4%) and the same week of 2015 (2.1%) (Figure 2). Mongolia There has been a steady increase in ILI activity in Mongolia since week 30 until week 37 (Figure 3). Republic of Korea In week 38, overall weekly ILI rate was 3.9/1,000 outpatients, which is lower than 4.6 recorded in the previous week and the national baseline of 11.3/1,000 outpatients (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatient ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 14 September 2016, influenza activity is low and following seasonal trends (Figure 5). Figure 5: Number of influenza cases reported weekly per reporting sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 38 of 2016, ILI or ARI activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance As of week 38, there is an increase in local influenza activity. The average consultation rate for ILI among sentinel general outpatient clinics was 6.4 ILI cases per 1,000 consultations, which is an increase from 4.6 ILI cases per 1,000 consultations recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 47.7 ILI cases per 1,000 consultations, which was higher than 46.4 ILI cases per 1,000 consultations recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 38 which tested positive for seasonal influenza viruses was 14.4%. This is higher than 7.8% recorded in the previous week. Influenza A (H3) was the predominant circulating subtype comprising 97.1% of positive respiratory specimens. Other viruses detected were influenza B (2.1%), influenza A (H1) (0.6%), and influenza C virus (0.2%). China (South) - ILI Surveillance During week 38, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in southern China was 2.9%. This is higher than the previous week of 2016 (2.6%) and the same week of 2015 (2.5%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI was 2,566 (over 5.5 working days) in week 37, an increase from previous week of 2,371 in week 36 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 1.3%. The overall influenza virus positivity of ILI samples (n=164) in the community was 31.7% in the past 4 weeks. Of the specimens tested positive for influenza virus in August 2016, 85.0% were positive for influenza A(H3N2), 13.1% for influenza B and 1.9% for influenza A(H1N1)pdm09. Source: https://www.moh.gov.sg/content/moh_web/home/statistics/infectiousDiseasesStatistics/weekly_infect iousdiseasesbulletin.html). Influenza Situation Update | 5 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for ARI, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza Situation Update | 6 Countries in the temperate zone of the southern hemisphere In the temperate zone of the southern hemisphere, influenza activity followed seasonal trends, declining in Australia and remaining at low levels in New Zealand. Australia – Laboratory-confirmed influenza As of 16 September 2016, a total of 66,648 notifications of laboratory confirmed influenza were reported to the National Notifiable Diseases Surveillance System (Figure 10). Ninety percent of notifications were influenza A (71% A(unsubtyped), 7% influenza A(H1N1)pdm09 and 11% influenza A (H3N2), 10% were influenza B and less than 1% were influenza C, influenza A&B co-infections or untyped. Source: http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu- flucurr.htm/$File/Australian-Influenza-Surveillance-Report.pdf Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness In week 37, ending 18 September 2016, 48 patients with ILI consulted sentinel general practices in 20 District Health Boards. The weekly ILI incidence was 9.1 per 100 000 patient population. Of the 30 tested ILI cases, 16 were positive for influenza viruses. This gives an ILI related influenza incidence (adjusted) of 4.9 per 100 000 patient population. Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Influenza Situation Update | 7 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 37, the number of ILI cases reported in Guam and Marshall Islands shows an increasing trend and are above the threshold of 90% historical value (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Influenza Situation Update | 8 Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY


 Virological Surveillance Summary The number of specimens provided to FluNet by each of the Western Pacific Region countries and areas that reported between week 1 and week 33, and the number of Influenza posiGve specimens are presented in the table below. 
 Table 1: Countries and areas reporGng data to FluNet, Western Pacific Region, weeks 1 to 33, 2016 
 Country (most recent week) Total number (%) of specimens processed Total number of influenza posiGve specimens China (week 33) 375,771 64,177 Republic of Korea (week 33) 6,969 1,285 Mongolia (week 30) 2,688 335 Lao People's DemocraGc Republic (week 33) 3,285 169 Malaysia (week 26) 2,237 179 Singapore (week 29) 1,438 836 Australia (week 33) 13,913 2,026 New Caledonia (week 28) 810 173 Philippines (week 32) 662 170 Viet Nam (week 32) 771 274 Papua New Guinea (week 32) 377 143 Fiji (week 30) 310 117 Cambodia (week 31) 853 194 Japan (week 25) N/A 6,526 New Zealand (week 31) 540 123 Influenza SituaGon Update | 1 Bi-weekly Influenza SituaGon Update
 30 August 2016 Figure 1: Number of influenza posiGve specimens by subtype and week, 
 Western Pacific Region, 2015-16 (accessed 29 August 2016) 
 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpaGent and inpaGent senGnel surveillance systems. Case definiGons, populaGons under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where rouGne surveillance is conducted and informaGon is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory InfecGons (SARI). The WHO surveillance case definiGon for ILI is an acute respiratory infecGon with a measured fever of
 ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infecGon with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalizaGon. 
 Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza acGvity remained at low levels. OutpaGent ILI Surveillance China (North) 
 During week 33, 2016, the percentage (%) of ILI visits at naGonal senGnel hospitals in Northern China was 2.4%. This is higher than last week (week 32) and the same as week 33 of 2014 (both 2.3%), but lower than the same week of 2015 (2.5%) (Figure 2). Mongolia Since week 30, 2016, there has been a steady increase in ILI acGvity in Mongolia (Figure 3). Influenza SituaGon Update | 2 Republic of Korea In week 33, 2016, the rate of ILI paGent visits to senGnel physicians was 4.5 /1,000 outpaGents which is below the naGonal baseline of 11.3/1,000 outpaGents (Figure 4). Republic of Korea Figure 4: Weekly proporGon of ILI visits per 1,000 paGents 2012-2016 
 (Source: Korean Centre for Disease Control and PrevenGon) China (North) Figure 2: Percentage of visits for ILI at senGnel hospitals, 2012-2016 (Source: China NaGonal Influenza Center) Mongolia Figure 3: ProporGon of outpaGent ILI visits (per 10,000 people), 2014-2016 (Source: Mongolia NaGonal Influenza Center) Influenza SituaGon Update | 3 SenGnel influenza surveillance Japan As of 24 August 2016, the number of influenza cases reported weekly was 0.02 per senDnel hospital sites. The seasonal pakern remains similar to that seen in the majority of previous years (Figure 5). Figure 5: Number of influenza cases reported weekly per reporGng senGnel hospital site, Japan 2006-2016 
 (Source: Japan NaGonal InsGtute of InfecGous Diseases) Countries/areas in the tropical zone In weeks 1 to 33 of 2016, ILI or Acute Respiratory InfecGon (ARI) acGvity followed previous seasonal trends in countries/areas in the tropical zone. OutpaGent Surveillance
 
 Hong Kong (China) - ILI Surveillance During week 33, the latest surveillance data showed that local influenza acGvity remained at a low level. The average consultaGon rate for influenza-like illness (ILI) among senGnel general outpaGent clinics was 3.8 ILI cases per 1,000 consultaGons, which was lower than 3.9 ILI cases per 1,000 consultaGons recorded in the previous week (Figure 6). The average consultaGon rate for ILI among senGnel private doctors was 35.4 ILI cases per 1,000 consultaGons, which was lower than 43.7 ILI cases per 1,000 consultaGons recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 33 which tested posiGve for seasonal influenza viruses was 4.11%. This is higher than 3.99% recorded in the previous week. Of all respiratory specimens tested in week 31, 127 (4.11%) tested posiGve for seasonal influenza viruses, including 5 (0.16%) influenza A (H1), 102 (3.30%) influenza A (H3), 15 (0.49%) influenza B and 5 (0.16%) influenza C. China (South) - ILI Surveillance During week 33, the percentage of outpaGent or emergency visits for ILI (ILI%) at naGonal senGnel hospitals in southern China was 2.8%. This is similar to last week(week 32), but lower than the same week of 2014 and 2015 (2.9% and 3.1% respecGvely) (Figure 8). Influenza SituaGon Update | 4 Singapore – ARI Surveillance The average daily number of paGents seeking treatment in polyclinics for ARI decreased from 3,233 (over 4.5 working days) in week 32 to 2,834 (over 5.5 working days) in week 33 (Figure 9). The proporGon of paGents with ILI among the polyclinic akendance for ARI remained low at 1.3 %. The overall prevalence of posiGve influenza cases among ILI samples (n=421) in the community was 46.8% in the past 4 weeks. Of the specimens that tested posiGve for influenza in July 2016, 8.1% were posiGve for influenza B, 3.2% for influenza A(H1N1)pdm09, and 88.7% for influenza A(H3N2). Source: hkps://www.moh.gov.sg/content/moh_web/home/staGsGcs/infecGousDiseasesStaGsGcs/ weekly_infecGousdiseasesbulleGn.html). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultaGon rates at senGnel general outpaGent clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health ProtecGon) Figure 7: ILI consultaGon rates at senGnel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health ProtecGon) 
 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at naGonal senGnel hospitals in South China, 2012-2016 (Source: China NaGonal Influenza Center) 
 Singapore - ARI Surveillance Figure 9: Average daily polyclinic akendances for Acute Respiratory InfecGon, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza SituaGon Update | 5 Countries in the temperate zone of the southern hemisphere Influenza acGvity remained at inter-seasonal levels in the reporGng countries of the southern hemisphere. Australia – Laboratory-confirmed influenza As of 05 August 2016, a total of 25,335 noGficaGons of laboratory confirmed influenza were reported to the NaGonal NoGfiable Diseases Surveillance System (Figure 10). In the most recent fortnight, 92% of noGficaGons were influenza A (63% A(unsubtyped), 8% influenza A(H1N1)pdm09 and 21% influenza A (H3N2)), 8% were influenza B and less than 1% were influenza A and B co-infecGons or untyped. Source: hkp://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu-flucurr.htm/$File/ Australian-Influenza-Surveillance-Report.pdf Figure 10: Australian noGficaGons of laboratory confirmed influenza 
 (Source: NaGonal NoGfiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness In week 33, 117 paGents were reported with ILI through senGnel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 22.2 ILI cases per 100,000 residents (Figure 11). Of the 48 tested ILI cases, 22 were posiGve for influenza virus, giving an ILI associated influenza incidence (adjusted) of 10.2 per 100,000 paGent populaGon. 
 Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand 
 (Source: InsGtute of Environmental Science and Research Ltd (ESR), New Zealand) Influenza SituaGon Update | 6 Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 33, the number of ILI cases reported was higher than the previous week in American Samoa and Fiji . The number of ILI cases in Guam, Tonga, Vanuatu and Palau decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 
 Global influenza situaGon updates Epidemiological update: hkp://www.who.int/influenza/surveillance_monitoring/updates/ latest_update_GIP_surveillance/en/ Virological update: hkp://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: hkp://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composiGon of influenza virus vaccines for use in the 2016 southern hemisphere influenza season hkp://www.who.int/influenza/vaccines/virus/recommendaGons/2016_south/en/ Influenza SituaGon Update | 7 AnGgenic and geneGc characterisGcs of zoonoGc influenza viruses and candidate vaccine viruses developed for potenGal use in human vaccines hkp://www.who.int/influenza/vaccines/virus/characterisGcs_virus_vaccines/en/ 4th WHO Informal ConsultaGon on Improving Influenza Vaccine Virus SelecGon hkp://www.who.int/ influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selecGon/en/ Video on influenza on WHO's YouTube Channel Arabic: hkps://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: hkps://www.youtube.com/watch?v=xW9gDKEPitQ English: hkps://www.youtube.com/watch?v=yhhJfT86Bgg French: hkps://www.youtube.com/watch?v=8mo8rWWJZkc Russian: hkps://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: hkps://www.youtube.com/watch?v=qXr75cKxwTY Influenza SituaGon Update | 8


 Virological Surveillance Summary The number of specimens provided to FluNet by each of the Western Pacific Region countries and areas that reported between week 1 and week 31, and proporDon of all specimens contributed by each country is presented in the table below. Table 1: Countries and areas reporDng data to FluNet, Western Pacific Region, weeks 1 to 31, 2016 
 Figure 1: Number of specimens posiDve for influenza by subtype and week, 
 Western Pacific Region, 2015-16 (accessed 15 August 2016) Influenza SituaDon Update | 1 Bi-weekly Influenza SituaDon Update 16 August 2016 Country Total (%) China 391,048 (95.6) Republic of Korea 6,634 (1.6) Mongolia 2,688 (0.7) Lao People's Democratic Republic 2,209 (0.5) Malaysia 1,648 (0.4) Singapore 1,438 (0.4) Australia 901 (0.2) New Caledonia 810 (0.2) Philippines 645 (0.2) Viet Nam 584 (0.1) Papua New Guinea 360 (0.1) Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpaDent and inpaDent senDnel surveillance systems. Case definiDons, populaDons under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where rouDne surveillance is conducted and informaDon is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory InfecDons (SARI). The WHO surveillance case definiDon for ILI is an acute respiratory infecDon with a measured fever of
 ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infecDon with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalizaDon. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza acDvity remained at low levels. OutpaDent ILI Surveillance China (North) 
 During week 31, 2016, the percentage (%) of visits for ILI at naDonal senDnel hospitals in north China was 2.5%,same as last week and the same week of 2014 (both 2.5%), higher than the same week of 2015 (2.4%) (Figure 2). Mongolia In week 31, 2016, ILI acDvity in Mongolia conDnued to decrease (Figure 3). Republic of Korea In week 31, 2016, the rate of ILI paDent visits to senDnel physicians was 4.7/1,000 outpaDents which is below the naDonal baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at senDnel hospitals, 2012-2016 (Source: China NaDonal Influenza Center) Mongolia Figure 3: ProporDon of outpaDents that were ILI (per 10,000 people), 2014-2016 (Source: Mongolia NaDonal Influenza Center) Influenza SituaDon Update | 2 SenDnel influenza surveillance Japan As of 10 August 2016, the number of influenza cases reported weekly was 0.02 per senDnel hospital sites. This follows the seasonal pafern (Figure 5). Figure 5: Number of influenza cases reported weekly per senDnel hospital site, Japan 2006-2016 
 (Source: Japan NaDonal InsDtute of InfecDous Diseases) Republic of Korea Figure 4: Weekly proporDon of ILI visits per 1,000 paDents 2012-2016 (Source: Korean Centre for Disease Control and PrevenDon) Influenza SituaDon Update | 3 Countries/areas in the tropical zone In weeks 1 to 31 of 2016, ILI or Acute Respiratory InfecDon (ARI) acDvity followed previous seasonal trends in countries/areas in the tropical zone. OutpaDent Surveillance Hong Kong (China) - ILI Surveillance During week 31, the latest surveillance data showed that local influenza acDvity remained at a low level. The average consultaDon rate for influenza-like illness (ILI) among senDnel general outpaDent clinics was 3.9 ILI cases per 1,000 consultaDons, which was lower than 4.1 recorded in the previous week (Figure 6). The average consultaDon rate for ILI among senDnel private doctors was 49.2 ILI cases per 1,000 consultaDons, which was lower than 54.1 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 31 which tested posiDve for seasonal influenza viruses was 4.11%, which was higher to the record of 3.99% in the previous week. Of all respiratory specimens tested in week 31, 127 (4.11%) tested posiDve for seasonal influenza viruses, including 5 (0.16%) influenza A (H1), 102 (3.30%) influenza A (H3), 15 (0.49%) influenza B and 5 (0.16%) influenza C. China (South) - ILI Surveillance During week 31, the percentage of outpaDent or emergency visits for ILI (ILI%) at naDonal senDnel hospitals in south China was 2.8%, lower than last week (3.1%), and lower than the same week of 2014 and 2015 (3.4% and 3.8%) (Figure 8). Singapore – ARI Surveillance The average daily number of paDents seeking treatment in polyclinics for ARI increased from 3,566 (over 5.5 working days) in week 30 to 3,499 (over 5.5 working days) in week 29 (Figure 9). The proporDon of paDents with ILI among the polyclinic afendances for ARI remained low at 2.1 %. The overall prevalence of influenza among ILI samples (n=481) in the community was 57.4% in the past 4 weeks. Of specimens that tested posiDve for influenza in June 2016, 8.1% were posiDve for influenza B, 3.2% for influenza A(H1N1)pdm09, and 88.7% for influenza A(H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultaDon rates at senDnel general outpaDent clinics, Hong Kong 2012-2016 
 (Source: Hong Kong Centre for Health ProtecDon) Figure 7: ILI consultaDon rates at senDnel private doctors, 
 Hong Kong 2012-2016 
 (Source: Hong Kong Centre for Health ProtecDon) Influenza SituaDon Update | 4 Countries in the temperate zone of the southern hemisphere Influenza acDvity remained at inter-seasonal levels in most of the reporDng countries in the southern hemisphere. Australia – Laboratory-confirmed influenza As of 22 July 2016, a total of 17,830 noDficaDons of laboratory confirmed influenza were reported (Figure 10). In the most recent fortnight, 90% of noDficaDons were influenza A (57% A(unsubtyped), 12% influenza A(H1N1)pdm09 and 21% influenza A (H3N2)), 10% were influenza B and less than 1% were influenza A and B co-infecDons or untyped. Figure 10: Australian noDficaDons of laboratory confirmed influenza 
 (Source: NaDonal NoDfiable Diseases Surveillance System, Australian Department of Health) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at naDonal senDnel hospitals in South China, 2012-2016 
 (Source: China NaDonal Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic afendances for
 Acute Respiratory InfecDon, Singapore 2015-2016 
 (Source: Singapore Ministry of Health) Influenza SituaDon Update | 5 New Zealand – Influenza like Illness In week 31, 95 paDents were reported with ILI through senDnel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 18.0 ILI cases per 100,000 residents (Figure 11). Of the 29 tested ILI cases, 13 were posiDve for influenza virus, giving an ILI associated influenza incidence (adjusted) of 6.7 per 100,000 paDent populaDon. 
 Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand 
 (Source: InsDtute of Environmental Science and Research Ltd (ESR), New Zealand) Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 31 the number of ILI cases reported was higher than the previous week in American Samoa and Fiji . The number of ILI cases in Guam, Tonga, Vanuatu and Palau decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza SituaDon Update | 6 Global influenza situaDon updates Epidemiological update:hfp://www.who.int/influenza/surveillance_monitoring/updates/ latest_update_GIP_surveillance/en/ Virological update: hfp://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: hfp://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composiDon of influenza virus vaccines for use in the 2016 southern hemisphere influenza season: hfp://www.who.int/influenza/vaccines/virus/recommendaDons/2016_south/en/ AnDgenic and geneDc characterisDcs of zoonoDc influenza viruses and candidate vaccine viruses developed for potenDal use in human vaccines: hfp://www.who.int/influenza/vaccines/virus/ characterisDcs_virus_vaccines/en/ 4th WHO Informal ConsultaDon on Improving Influenza Vaccine Virus SelecDon hfp://www.who.int/ influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selecDon/en/ Video on influenza on WHO's YouTube Channel Arabic: hfps://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: hfps://www.youtube.com/watch?v=xW9gDKEPitQ English: hfps://www.youtube.com/watch?v=yhhJfT86Bgg French: hfps://www.youtube.com/watch?v=8mo8rWWJZkc Russian: hfps://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: hfps://www.youtube.com/watch?v=qXr75cKxwTY Influenza SituaDon Update | 7

Bi-weekly Influenza Situation Update 02 August 2016 Virological Surveillance Summary The number of specimens provided to FluNet by each of the Western Pacific Region countries and areas that reported between week 1 and week 29, and proportion of all specimens contributed by each country is presented in the table below. Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 29, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 01 August 2016) Country Total (%) China 368,835 (95.6) Republic of Korea 6,309 (1.6) Mongolia 2,678 (0.7) Lao People's Democratic Republic 1,748 (0.5) Malaysia 1,648 (0.4) Singapore 1,438 (0.4) Australia 827 (0.2) New Caledonia 810 (0.2) Viet Nam 584 (0.2) Philippines 545 (0.1) Papua New Guinea 360 (0.1) Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 29, 2016, the percentage (%) of visits for ILI at national sentinel hospitals in north China was 2.5%, higher than last week, and lower than the same week of 2015 (2.6%), same as the same week of 2014 (2.5%) (Figure 2). Mongolia In week 29, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 29, 2016, the rate of ILI patient visits to sentinel physicians was 5.3/1,000 outpatients which is below the national baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 27 July 2016, the number of influenza cases reported weekly, 0.02 per sentinel hospital site, continued to decrease in line with the seasonal pattern (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 29 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 29, the latest surveillance data showed that local influenza activity remained at a low level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 4.6 ILI cases per 1,000 consultations, which was lower than 5.0 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 45.5 ILI cases per 1,000 consultations, which was higher than 36.0 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 29 which tested positive for seasonal influenza viruses was 3.37%, which was lower to the record of 3.73% in the previous week. Of all respiratory specimens tested in week 29, 109 (3.37%) tested positive for seasonal influenza viruses, including 1 (0.03%) influenza A (H1), 82 (2.53%) influenza A (H3), 17 (0.53%) influenza B and 9 (0.28%) influenza C. China (South) - ILI Surveillance During week 29, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.0% which was lower than the last week (3.1%) and lower than the same week of 2014 and 2015 (both 3.6%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI increased from 2,940 (over 5.5 working days) in week 28 to 3,427 (over 5.5 working days) in week 29 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 2.2 %. The overall prevalence of influenza among ILI samples (n=337) in the community was 65.6% in the past 4 weeks. Of specimens that tested positive for influenza in June 2016, 9.9% were positive for influenza B, 7.4% for influenza A(H1N1)pdm09, and 82.6% for influenza A(H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update | 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza activity remained at inter-seasonal levels in most of the reporting countries in the southern hemisphere. Australia – Laboratory-confirmed influenza As of 22 July 2016, a total of 17,830 notifications of laboratory confirmed influenza were reported (Figure 10). In the most recent fortnight, 90% of notifications were influenza A (57% A(unsubtyped), 12% influenza A(H1N1)pdm09 and 21% influenza A (H3N2)), 10% were influenza B and less than 1% were influenza A and B co-infections or untyped. Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) Influenza Situation Update | 6 New Zealand – Influenza like Illness In week 29, 96 patients were reported with ILI through sentinel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 18.2 ILI cases per 100,000 residents (Figure 11). Of the 38 tested ILI cases, 14 were positive for influenza virus, giving an ILI associated influenza incidence (adjusted) of 6.7 per 100,000 patient population. Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 29 the number of ILI cases reported was higher than the previous weeks in French Polynesia, Guan, Kiribati, and Vanuatu. The number of ILI cases in American Samoa, Fiji, and Palau decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 7 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 19 July 2016 Virological Surveillance Summary The number of specimens provided to FluNet by each of the Western Pacific Region countries and areas that reported between week 1 and week 27, and proportion of all specimens contributed by each country is presented in the table below. Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 27, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 18 July 2016) Country Total (%) China 351281 (95.7) Republic of Korea 5907 (1.6) Mongolia 2658 (0.7) Lao People's Democratic Republic 1748 (0.5) Malaysia 1648 (0.4) Singapore 1233 (0.3) Cambodia 610 (0.2) New Caledonia 605 (0.2) Philippines 519 (0.1) Viet Nam 404 (0.1) Papua New Guinea 358 (0.1) Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 26, 2016, the percentage (%) of visits for ILI at national sentinel hospitals in north China was 2.5%, the same as last week, and lower than the same week of 2014 and 2015 (both 2.6%) (Figure 2). Mongolia In week 26, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 28, 2016, the rate of ILI patient visits to sentinel physicians was 4.3/1,000 outpatients which is below the national baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 13 July 2016, the number of influenza cases reported weekly, 0.03 per sentinel hospital site, continued to decrease in line with the seasonal pattern (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 26 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 28, the latest surveillance data showed that local influenza activity remained at a low level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 5.0 ILI cases per 1,000 consultations, which was higher than 4.8 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 36.0 ILI cases per 1,000 consultations, which was lower than 49.1 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 28 which tested positive for seasonal influenza viruses was 2.89%, which was similar to the record of 2.88% in the previous week. Of all respiratory specimens tested in week 26, 100 (2.89%) tested positive for seasonal influenza viruses, including 6 (0.17%) influenza A (H1), 43 (1.25%) influenza A (H3), 45 (1.30%) influenza B and 6 (0.17%) influenza C. China (South) - ILI Surveillance During week 26, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.3% which was lower than the last week (3.4%) but the same as in 2014 and 2015 (3.5% and 4.1%) (Figure 8). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI increased from 3,021 (over 5.5 working days) in week 26 to 2,989 (over 5.5 working days) in week 27 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 2.2 %. The overall prevalence of influenza among ILI samples (n=195) in the community was 63.1% in the past 4 weeks. Of specimens that tested positive for influenza in June 2016, 9.9% were positive for influenza B, 7.4% for influenza A(H1N1)pdm09, and 82.6% for influenza A(H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update | 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza activity remained at inter-seasonal levels in most of the reporting countries in the southern hemisphere. Australia – Laboratory-confirmed influenza (No update) As of 24 June 2016, a total of 12,269 notifications of laboratory confirmed influenza were reported (Figure 10). In the most recent fortnight, 85% of notifications were influenza A (58% A(unsubtyped), 16% influenza A(H1N1)pdm09 and 11% influenza A (H3N2)), 14% were influenza B and less than 1% were influenza A and B co-infections or untyped. Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness In week 27, 91 patients were reported with ILI through sentinel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 17.3 ILI cases per 100,000 residents (Figure 11). Of the 37 tested ILI cases, 16 were positive for influenza virus, giving an ILI associated influenza incidence (adjusted) of 7.5 per 100,000 patient population. Influenza Situation Update | 6 Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 27 the number of ILI cases reported was higher than the previous weeks in Cook Islands, Federated States of Micronesia, French Polynesia, Palau, and Tonga. The number of ILI cases in American Samoa, Guam, Kiribati, Nauru and Vanuatu decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 7 Global influenza situation updates Epidemiological:update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season. http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 05 July 2016 Virological Surveillance Summary In the WHO Western Pacific Region, influenza virus B (Victoria lineage) predominated during week 25, 2016. The number of specimens provided to FluNet by each of the Western Pacific Region countries and areas that reported between week 1 and week 25, and proportion of all specimens contributed by each country is presented in the table below. Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 25, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 04 July 2016) Country Total (%) China 331434 (95.7) Republic of Korea 5547 (1.6) Mongolia 2638 (0.8) Lao People's Democratic Republic 1748 (0.5) Malaysia 1648 (0.5) Singapore 1004 (0.3) Cambodia 610 (0.2) New Caledonia 605 (0.2) Philippines 481 (0.1) Viet Nam 404 (0.1) Papua New Guinea 285 (0.1) Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) (No update) During week 21 2016, the percentage (%) of visits for ILI at national sentinel hospitals in north China was 2.4%, the same as last week, and lower than the same week in 2014 (2.5%), but higher than the same week in 2015 (2.3%) (Figure 2). Mongolia In week 24, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 25, 2016, the rate of ILI patient visits to sentinel physicians was 5.1/1,000 outpatients which is below the national baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 29 June 2016, the number of influenza cases reported weekly, 0.04 per sentinel hospital site, continued to decrease in line with the seasonal pattern (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 25 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 26, the latest surveillance data showed that local influenza activity increased compared with the past few weeks. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 6.7 ILI cases per 1,000 consultations, which was higher than 4.5 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 45.5 ILI cases per 1,000 consultations, which was higher than 39.5 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 26 which tested positive for seasonal influenza viruses was 2.89%, which was similar to the record of 2.88 in the previous week. Of all respiratory specimens tested in week 26, 100 (2.89%) tested positive for seasonal influenza viruses, including 6 (0.17%) influenza A (H1), 43 (1.25%) influenza A (H3), 45 (1.30%) influenza B and 6 (0.17%) influenza C. China (South) - ILI Surveillance (No update) During week 21, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.3% which was lower than the last week (3.4%) but the same as in 2014 and 2015 (3.3%) (Figure 8). In South China, influenza B was the predominant type of influenza detected (78.3%). Of the influenza B subtypes, Victoria lineage was predominant (72.9%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI increased from 2,564 (over 5.5 working days) in week 24 to 2,819 (over 5.5 working days) in week 25 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 2.1 %. The overall prevalence of influenza among ILI samples (n=130) in the community was 63.1% in the past 4 weeks. Of specimens that tested positive for influenza in April 2016, 55.1% were positive for influenza B, 30.6% for influenza A(H1N1)pdm09, and 14.3% for influenza A(H3N2). Influenza Situation Update | 5 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza activity remained at inter-seasonal levels in most of the reporting countries in the southern hemisphere. Australia – Laboratory-confirmed influenza As of 24 June2016, a total of 12,269 notifications of laboratory confirmed influenza were reported (Figure 10). In the most recent fortnight, 85% of notifications were influenza A (58% A(unsubtyped), 16% influenza A(H1N1)pdm09 and 11% influenza A (H3N2)), 14% were influenza B and less than 1% were influenza A and B co-infections or untyped. Influenza Situation Update | 6 Figure 10: Australian notifications of laboratory confirmed influenza (Source: National Notifiable Diseases Surveillance System, Australian Department of Health) New Zealand – Influenza like Illness In week 25, 31 patients were reported with ILI through sentinel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 13.5 ILI cases per 100,000 residents (Figure 11). Of the 38 tested ILI cases, 5 were positive for influenza virus, giving an ILI associated influenza incidence (adjusted) of 1.8 per 100,000 patient population. Figure 11: Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 25 the number of ILI cases reported was higher than the previous weeks in American Samoa, Cook Islands, Federated States of Micronesia, Marshall Islands and Vanuatu. The number of ILI cases in Fiji, Kiribati, Niue and Tonga decreased from the previous week (Figure 12). Influenza Situation Update | 7 Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Influenza Situation Update | 8 Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Influenza Situation Update| 1 Bi-weekly Influenza Situation Update 21 June 2016 Virological Surveillance Summary In the WHO Western Pacific Region, influenza virus B (Victoria lineage) predominated during week 23, 2016. The number of specimens provided to FluNet by each of the Western Pacific Region countries and areas that reported between week 1 and week 23, and proportion of all specimens contributed by each country is presented in the table below. Table 1: Countries and areas reporting data to FluNet, Western Pacific Region, weeks 1 to 23, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 20 June 2016) Country Total (%) Cambodia 530 (0.2) China 310819 (95.8) Lao People's Democratic Republic 1632 (0.5) Mongolia 2628 (0.8) New Caledonia 605 (0.2) Philippines 467 (0.1) Republic of Korea 5170 (1.6) Singapore 1004 (0.3) Viet Nam 283 (0.1) Papua New Guinea 285 (0.1) Influenza Situation Update| 2 Bi-weekly Influenza Situation Update 21 June 2016 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) (No update) During week 21 2016, the percentage (%) of visits for ILI at national sentinel hospitals in north China was 2.4%, the same as last week, and lower than the same week in 2014 (2.5%), but higher than the same week in 2015 (2.3%) (Figure 2). Mongolia In week 23, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 24, 2016, the rate of ILI patient visits to sentinel physicians was 4.5 /1,000 outpatients which is below the national baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update| 3 Bi-weekly Influenza Situation Update 21 June 2016 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 15 June 2016, the number of influenza cases reported weekly, 0.13 per sentinel hospital site, continued to decrease in line with the seasonal pattern (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update| 4 Bi-weekly Influenza Situation Update 21 June 2016 Countries/areas in the tropical zone In weeks 1 to 23 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 24, the latest surveillance data showed that local influenza activity remained at a low level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 5.5 ILI cases per 1,000 consultations, which was lower than 5.6 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 32.6 ILI cases per 1,000 consultations, which was lower than 44.5 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 24 which tested positive for seasonal influenza viruses was 3.42%, slightly lower than that recorded in the previous week (3.52%). Of all respiratory specimens tested in week 24, 113 (3.42%) tested positive for seasonal influenza viruses, including 22 (0.67%) influenza A (H1), 9 (0.27%) influenza A (H3), 72 (2.18%) influenza B and 10 (0.30%) influenza C. China (South) - ILI Surveillance (No update) During week 21, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.3% which was lower than the last week (3.4%) but the same as in 2014 and 2015 (3.3%) (Figure 8). In South China, influenza B was the predominant type of influenza detected (78.3%). Of the influenza B subtypes, Victoria lineage was predominant (72.9%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI decreased from 2,634 (over 5.5 working days) in week 22 to 2,521 (over 5.5 working days) in week 23 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 1.5 %. The overall prevalence of influenza among ILI samples (n=119) in the community was 51.3% in the past 4 weeks. Of specimens that tested positive for influenza in April 2016, 55.1% were positive for influenza B, 30.6% for influenza A(H1N1)pdm09, -and 14.3% for influenza A(H3N2). Influenza Situation Update| 5 Bi-weekly Influenza Situation Update 21 June 2016 Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza activity remained at inter-seasonal levels in most of the reporting countries in the southern hemisphere. New Zealand – Influenza like Illness In week 23, 45 patients were reported with ILI through sentinel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 9.4 ILI cases per 100,000 residents (Figure 10). This is below the seasonal threshold of ILI consultations (Figure 11). Of the 11 tested ILI cases, none were positive for influenza virus, giving an ILI associated influenza incidence (adjusted) of 0.0 per 100, 000 patient population. Influenza Situation Update| 6 Bi-weekly Influenza Situation Update 21 June 2016 Figure 10. Weekly resident ILI and influenza incidence since (Week 18) 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Figure 11: Weekly incidence rates for influenza-like illness in New Zealand in 2016 (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 22 the number of ILI cases reported was higher than the previous weeks in American Samoa, Federated States of Micronesia, Niue, and Vanuatu. The number of ILI cases in Fiji, New Caledonia and Northern Mariana Islands decreased from the previous week (Figure 12). Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update| 7 Bi-weekly Influenza Situation Update 21 June 2016 Global influenza situation updates Epidemiological update:http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/en/ Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 7 June 2016 Virological Surveillance Summary In the WHO Western Pacific Region, influenza virus B (Victoria lineage) predominated during week 21, 2016. The number of specimens provided to FluNet by each of the Western Pacific Region countries that reported between week 1 and week 21, and proportion of all specimens contributed by each country is presented in the table below. Table 1: Countries providing specimens for FluNet, Western Pacific Region, weeks 1 to 21, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 6 June 2016) Country Total (%) Cambodia 461 (0.2) China 289741 (96.1) Lao People's Democratic Republic 1259 (0.4) Mongolia 2531 (0.8) New Caledonia 559 (0.2) Philippines 432 (0.1) Republic of Korea 4801 (1.6) Singapore 956 (0.3) Viet Nam 283 (0.1) Papua New Guinea 285 (0.1) Influenza Situation Update| 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 21 2016, the percentage (%) of visits for ILI at national sentinel hospitals in north China was 2.4%, the same as last week, and lower than the same week in 2014 (2.5%), but higher than the same week in 2015 (2.3%) (Figure 2). Mongolia In week 21, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 22, 2016, the rate of ILI patient visits to sentinel physicians was 5.4 /1,000 outpatients which is below the national baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update| 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 29 May 2016, the number of influenza cases reported weekly, 0.29 per sentinel hospital site, continued to decrease in line with the seasonal pattern (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Countries/areas in the tropical zone In weeks 1 to 21 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 22, the latest surveillance data showed that local influenza activity remained at a low level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 6.1 ILI cases per 1,000 consultations, which was lower than 6.8 recorded in the previous week (Figure 6). Influenza Situation Update| 4 The average consultation rate for ILI among sentinel private doctors was 40.7 ILI cases per 1,000 consultations, which was lower than 42.7 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 22 which tested positive for seasonal influenza viruses was 6.26%, lower than that recorded in the previous week (8.50%). Of all respiratory specimens tested in week 22, 237 (6.26%) tested positive for seasonal influenza viruses, including 35 (0.90%) influenza A (H1), 22 (0.58%) influenza A (H3), 157 (4.15%) influenza B and 23 (0.61%) influenza C. China (South) - ILI Surveillance During week 21, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.3% which was lower than the last week (3.4%) but the same as in 2014 and 2015 (3.3%) (Figure 8). In South China, influenza B was the predominant type of influenza detected (78.3%). Of the influenza B subtypes, Victoria lineage was predominant (72.9%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI decreased from 2,853 (over 5.0 working days) in week 20 to 2,775 (over 5.5 working days) in week 21 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at 1.1 %. The overall prevalence of influenza among ILI samples (n=134) in the community was 34.3% in the past 4 weeks. Of specimens that tested positive for influenza in April 2016, 60.5% were positive for influenza B, 26.3% for influenza A(H1N1) pdm09, and 13.2% for influenza A(H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update| 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza activity remained at inter-seasonal levels in most of the reporting countries in the southern hemisphere. New Zealand – Influenza like Illness In week 21, 52 patients were reported with ILI through sentinel surveillance in 20 District Health Boards, with a weekly ILI incidence rate of 10.7 per 100,000 (Figure 10). This is below the seasonal threshold of ILI consultations (Figure 11). Three out of 16 ILI cases tested were positive for influenza virus, giving an ILI related influenza incidence (adjusted) of 2.0 per 100, 000 patient population. Figure 10. Weekly resident ILI and influenza incidence since 2 May 2016 in New Zealand (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Figure 11: Weekly incidence rates for influenza-like illness in New Zealand in 2016 (Source: Institute of Environmental Science and Research Ltd (ESR), New Zealand) Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 21 the number of ILI cases reported is higher than the previous weeks in Fiji and Cook Islands. The number of ILI cases in French Polynesia and New Caledonia are decreasing compared to the previous week (Figure 12). Influenza Situation Update| 6 Figure 12: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Global influenza situation updates Epidemiological update: http://http://www.who.int/influenza/surveillance_monitoring/updates/2016_05_30_surveillance_update_264.pdf Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Influenza Situation Update| 7 Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 24 May 2016 Virological Surveillance Summary In the WHO Western Pacific Region, influenza virus B (Victoria lineage) was predominated during week 19, 2016. The number of specimens provided to FluNet by each of the Western Pacific Region countries that reported between week 1 and week 19, and proportion of all specimens contributed by each country is presented in the table below. Table 1: Countries providing specimens for FluNet, Western Pacific Region, weeks 1 to 19, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 23 May 2016) Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). Country Total (%) Cambodia 483 (0.17) China 267445 (95.95) Lao People's Democratic Republic 1332 (0.48) Mongolia 2479 (0.89) New Caledonia 492(0.18) Philippines 442 (0.16) Republic of Korea 4615 (1.66) Singapore 877 (0.31) Viet Nam 291 (0.10) Papua New Guinea 285 (0.10) Influenza Situation Update | 2 The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) During week 19 2016, percentage (%) of visits for ILI at national sentinel hospitals in north China was 2.4%, lower than last week and the same week of 2014 (2.6% and 2.5%), but higher than the same week in 2015 (2.3%) (Figure 2). Mongolia In week 19, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 20, 2016, the rate of ILI patient visits to sentinel physicians decreased (6.3 /1,000 outpatients) below the national baseline of 11.3/ 1,000 (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Influenza Situation Update | 3 Sentinel influenza surveillance Japan As of 17 May 2016, the number of influenza cases reported weekly, 1.24 per sentinel hospital site, continued to decrease in line with the seasonal pattern (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Countries/areas in the tropical zone In weeks 1 to 19 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 20, the latest surveillance data showed that local influenza activity has almost returned to baseline level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 6.5 ILI cases per 1,000 consultations, which was same as that in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 43.4 ILI cases per 1,000 consultations, similar to 43.1 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 20 which tested positive for seasonal influenza viruses was 9.46%, lower than that recorded in the previous week (11.45%). Of all respiratory specimens tested in week 20, 325 (9.46%) tested positive for seasonal influenza viruses, including 96 (2.8%) influenza A (H1), 21 (0.6%) influenza A (H3), 195 (5.75%) influenza B and 13 (0.4%) influenza C. China (South) - ILI Surveillance During week 19, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.5%, lower than the last week 3.7% but higher than the corresponding weeks in 2014 and 2015 (3.0% and 2.9%) (Figure 8). In South China, influenza B was the predominant type of influenza detected (78.3%). Of the influenza B subtypes, B Victoria was the most common (72.9%). Influenza Situation Update | 4 Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI decreased from 2,715 (over 4.5 working days) in week 18 to 2,648 (over 5.5 working days) in week 19 (Figure 9). The proportion of patients with ILI among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=110) in the community was 34.5% in the past 4 weeks. Of specimens that tested positive for influenza in April 2016, 60.5% were positive for influenza B, 26.3% for influenza A (H1N1) pdm, and 13.2% for influenza A (H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Influenza Situation Update | 5 Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 19 the number of ILI cases reported is higher than the previous weeks in the Marshall Islands. The number of ILI cases in American Samoa, Fiji and Federated States of Micronesia are decreasing compared to the high numbers reported in previous weeks. (Fig. 10) Figure 10: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_05_16_surveillance_update_263.pdf Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/vaccines/virus/4thmtg_improve_vaccine_virus_selection/en/ Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 26 April 2016 Virological Surveillance Summary In the Western Pacific Region, the following influenza viruses predominated: Table 1: Predominant influenza viruses, Western Pacific Region, 2015 to week 15 2016 Year Week Predominant viruses 2015 1-9 A (H3) 10-16 B (Yamagata lineage), B (lineage not determined) 17-19 B (Yamagata lineage), A (H3) 20-37 A (H3) 38-42 A (H3), B (lineage not determined) 43-51 Influenza virus activity is low in all subtypes 52-53 A (H3), A (H1N1) pdm09 2016 1-15 A (H1N1) pdm09 The number of specimens provided to FluNet by each of the Western Pacific Region countries that reported between week 1 and week 15, and proportion of all specimens contributed by each country is presented in the table below. Table 2: Countries providing specimens for FluNet, Western Pacific Region, weeks 1 to 15, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 26 April 2016) Country Total Cambodia 389 China 272465 Lao People's Democratic Republic 1068 Mongolia 2224 New Caledonia 426 Philippines 391 Republic of Korea 3722 Singapore 877 Viet Nam 207 Papua New Guinea 285 Influenza Situation Update| 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) In week 15 2016, ILI activity decreased slightly. The proportion of hospital visits that were for ILI at national sentinel hospitals in north China in week 15 was 2.8%, compared to 3.2% in week 14 of 2016, and 2.6% and 2.5% in the corresponding weeks of 2014 and 2015 respectively (Figure 2). Mongolia In week 15, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 16, 2016, the rate of ILI patient visits to sentinel physicians decreased (21.1 /1,000 outpatients) but is still higher than that of previous years (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2012-2016 (Source: China National Influenza Center) Mongolia Figure3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update| 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 20 April 2016, the number of influenza cases reported weekly per sentinel hospital site continued to decrease in line with the seasonal pattern (Error! Reference source not found.). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update| 4 Countries/areas in the tropical zone In weeks 1 to 15 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 16, overall influenza activity is decreasing but is still higher than the previous years. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 6.6 ILI cases per 1,000 consultations, compared to 8.4 per 1,000 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 58.5 ILI cases per 1,000 consultations, similar to 57.9 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 16 which tested positive for seasonal influenza viruses was 16.7%, slightly lower than that recorded in the previous week (17.5%). Of all respiratory specimens tested in week 16, 678 (16.7%) tested positive for seasonal influenza viruses, including; 293 (7.2%) influenza A (H1), 18 (0.4%) influenza A (H3), 346 (8.5%) influenza B and 21 (0.5%) influenza C. China (South) - ILI Surveillance During week 15, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.7%, lower than the previous week (4.0%), and was higher than the corresponding weeks of 2014 and 2015 (3.1% and 2.8% respectively) (Figure 8). In South China, influenza B was the predominant type of influenza detected (73.7%). Of the influenza B subtypes, B Victoria was the most common (72.6%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI decreased from 2,417 (over 5.5 working days) in week 14 to 2,383 (over 5.5 working days) in week 15 (Figure 9). The proportion of patients with influenza-like illness (ILI) among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=129) in the community was 45.0% in the past 4 weeks. Of specimens that tested positive for influenza in March 2016, 72.9% were positive for influenza B, 21.4% for influenza A (H1N1) pdm09, and 5.7% for influenza A (H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update| 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2012-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 14, the number of ILI cases reported is higher than the previous weeks in American Samoa, Fiji, Kiribati, Northern Mariana Islands, Samoa and Tuvalu. (Figure 10) Figure 10: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update| 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_04_04_surveillance_update_260.pdf?ua=1 Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 12 April 2016 Virological Surveillance Summary In the Western Pacific Region, the following influenza viruses predominated: Table 1: Predominant influenza viruses, Western Pacific Region, 2015 to week 13 2016 Year Week Predominant viruses 2015 1-9 A (H3) 10-16 B (Yamagata lineage), B (lineage not determined) 17-19 B (Yamagata lineage), A (H3) 20-37 A (H3) 38-42 A (H3), B (lineage not determined) 43-51 Influenza virus activity is low in all subtypes 52-53 A (H3), A (H1N1) pdm09 2016 1-13 A (H1N1) pdm09 The number of specimens provided to FluNet by each of the Western Pacific Region countries that reported between week 1 and week 13, and proportion of all specimens contributed by each country is presented in the table below. Table 2: Countries providing specimens for FluNet, Western Pacific Region, weeks 1 to 13, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 12 April 2016) Country Total Cambodia 315 China 185519 Lao People's Democratic Republic 1017 Mongolia 2029 New Caledonia 337 Philippines 361 Republic of Korea 2979 Singapore 684 Viet Nam 116 Papua New Guinea 285 Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) In week 13 2016, ILI activity decreased slightly but is still high compared to previous years. The proportion of hospital visits that were for ILI at national sentinel hospitals in north China in week 13 was 3.7%, compared to 4.0% in week 12 of 2016, and 2.9% and 2.6% in the corresponding weeks of 2014 and 2015 respectively (Figure 2). Mongolia In week 13, 2016, ILI activity in Mongolia continued to decrease (Figure 3). Republic of Korea In week 14, 2016, the rate of ILI patient visits to sentinel physicians continues to increase (32.0 /1,000 outpatients). This trend is similar to that in last year (2014-2015). (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2011-2016 (Source: China National Influenza Center) Mongolia Figure3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 6 April 2016, the number of influenza cases reported weekly per sentinel hospital site continued to decrease in line with the seasonal pattern (Error! Reference source not found.). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Countries/areas in the tropical zone In weeks 1 to 14 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Influenza Situation Update | 4 Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 14, overall influenza activity remained at a high level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 8.2 ILI cases per 1,000 consultations, compared to 9.0 per 1,000 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 68.2 ILI cases per 1,000 consultations, increased from 58.9 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 14 which tested positive for seasonal influenza viruses was 18.6%, slightly lower than that recorded in the previous week (21.3%). Of all respiratory specimens tested in week 14, 979 (18.6%) tested positive for seasonal influenza viruses, including; 365 (6.9%) influenza A (H1), 30 (0.6%) influenza A (H3), 560 (10.6%) influenza B and 24 (0.5%) influenza C. China (South) - ILI Surveillance During week 13, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 4.0%, lower than the previous week (4.1%), and was higher than the corresponding weeks of 2014 and 2015 (3.0% and 2.5% respectively) (Figure 8). In South China, influenza B was the predominant type of influenza detected (72.6%). Of the influenza B subtypes, B Victoria was the most common (77.1%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI decreased from 2,596 (over 4.5 working days) in week 12 to 2,530 (over 5.5 working days) in week 13 (Figure 9). The proportion of patients with influenza-like illness (ILI) among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=198) in the community was 54.5% in the past 4 weeks. Of specimens that tested positive for influenza in March 2016, 72.9% were positive for influenza B, 21.4% for influenza A (H1N1) pdm09, and 5.7% for influenza A (H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update | 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2011-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, in week 13, the number of ILI cases reported is higher than the previous weeks in American Samoa, Fiji, Kiribati, Northern Mariana Islands, Samoa and Tuvalu. (Figure 10) Figure 10: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_04_04_surveillance_update_260.pdf?ua=1 Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 29 March 2016 Virological Surveillance Summary In the Western Pacific Region, the following influenza viruses predominated: Table 1: Predominant influenza viruses, Western Pacific Region, 2015 to week 11 2016 Year Week Predominant viruses 2015 1-9 A (H3) 10-16 B (Yamagata lineage), B (lineage not determined) 17-19 B (Yamagata lineage), A (H3) 20-37 A (H3) 38-42 A (H3), B (lineage not determined) 43-51 Influenza virus activity is low in all subtypes 52-53 A(H3), A(H1N1)pdm09 2016 1-11 A(H1N1)pdm09 The number of specimens provided to FluNet by each of the Western Pacific Region countries that reported between week 1 and week 10, and proportion of all specimens contributed by each country is presented in the table below. Table 2: Countries providing specimens for FluNet, Western Pacific Region, weeks 1 to 10, 2016 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 29 March 2016) Country Total Cambodia 242 China 155629 Lao People's Democratic Republic 698 Mongolia 1676 New Caledonia 212 Philippines 240 Republic of Korea 2233 Singapore 608 Viet Nam 32 Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) In week 11 2016, ILI activity had begun to increase. The proportion of hospital visits that were for ILI at national sentinel hospitals in north China in week 11 was 4.0%, compared to 3.8% in week 10 of 2016, and 2.9% and 2.6% in the corresponding week of 2014 and 2015 respectively (Figure 2). Mongolia In week 11, 2016, ILI activity in Mongolia has been following seasonal patterns however has surpassed the upper tolerance limit (Figure 3). Republic of Korea In week 12, 2016, the rate of ILI patient visits to sentinel physicians (30.1 /1,000 outpatients) followed the seasonal trend of previous years (2012-2015) and was above baseline (11.3/1,000 outpatients) (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2011-2016 (Source: China National Influenza Center) Mongolia Figure3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 23 March 2016, the number of influenza cases reported weekly per sentinel hospital site started decreasing, following the seasonal pattern (Error! Reference source not found.). Figure 1: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 10 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 12, overall influenza activity remained at a high level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 8.2 ILI cases per 1,000 consultations, which was lower than 10.0 per 1,000 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 69.7 ILI cases per 1,000 consultations, which was similar to 70.2 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 12 which tested positive for seasonal influenza viruses was 18.4%, slightly lower than that recorded in the previous week (22.1%). Of all respiratory specimens tested in week 12, 781 (18.4%) tested positive for seasonal influenza viruses, including; 315 (7.4%) influenza A (H1), 20 (0.5%) influenza A (H3), 437 (10.3%) influenza B and 9 (0.2%) influenza C. China (South) - ILI Surveillance During week 11, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.9%, higher than the previous week (3.6%), as well as the corresponding weeks of 2014 and 2015 (3.0% and 2.5% respectively) (Figure 8). In South China, influenza B was the predominant type of influenza detected (65.5%). Of the influenza B subtypes, B Victoria was the most common (69.4%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in polyclinics for ARI decreased from 2,702 (over 5.5 working days) in week 10 to 2,382 (over 5.5 working days) in week 11 (Figure 9). The proportion of patients with influenza-like illness (ILI) among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=277) in the community was 61.0% in the past 4 weeks. Of specimens that tested positive for influenza in February 2016, 61.1% were positive for influenza B, 22.7% for influenza A (H1N1) pdm09, and 16.2% for influenza A (H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update | 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2011-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, as of week 10, the number of ILI cases reported is higher than the previous weeks in French Polynesia, Vanuatu, Fiji, Guam, Kiribati and New Caledonia. (Figure 10) Figure 10: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_03_21_surveillance_update_259. pdf?ua=1 Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 16 March 2016 Virological Surveillance Summary In the Western Pacific Region, the following influenza viruses predominated: Table 1: Predominant influenza viruses, Western Pacific Region, 2015 to week 9 2016 Year Week Predominant viruses 2015 1-9 A (H3) 10-16 B (Yamagata lineage), B (lineage not determined) 17-19 B (Yamagata lineage), A (H3) 20-37 A (H3) 38-42 A (H3), B (lineage not determined) 43-51 Influenza virus activity is low in all subtypes 52-53 A(H3), A(H1N1)pdm09 2016 1-9 A(H1N1)pdm09 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 16 March 2016) Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Influenza Situation Update | 2 Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) In week 9 2016, ILI activity had begun to decrease. The proportion of hospital visits that were for ILI at national sentinel hospitals in north China in week 9 was 3.6%, compared to 3.5% in week 8 of 2016, and 2.8% and 2.9% in the corresponding week of 2014 and 2015 respectively (Figure 2). Mongolia In week 9, 2016, ILI activity in Mongolia has been following seasonal patterns however has surpassed the upper tolerance limit (Figure 3). Republic of Korea In week 9, 2016, the rate of ILI patient visits to sentinel physicians (43.0/1,000 outpatients) followed the seasonal trend of previous years (2012-2015) and was above baseline (11.3/1,000 outpatients) (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2011-2016 (Source: China National Influenza Center) Mongolia Figure3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Republic of Korea Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Influenza Situation Update | 3 Sentinel influenza surveillance Japan As of 9 March 2016, the number of influenza cases reported weekly per sentinel hospital site started decreasing, following the seasonal pattern. (Error! Reference source not found.). Figure 1: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 10 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 10, overall influenza activity remained at a high level. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics was 11.7 ILI cases per 1,000 consultations, which was lower than 9.5 per 1,000 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 82.3 ILI cases per 1,000 consultations, which was higher than 67.7 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 10 which tested positive for seasonal influenza viruses was 25.5%, slightly lower than that recorded in the previous week (26.5%). Of all respiratory specimens tested in week 10, 1303 (25.5%) tested positive for seasonal influenza viruses, including; 739 (14.5%) influenza A (H1), 43 (0.8%) influenza A (H3), 489 (9.6%) influenza B and 32 (0.6%) influenza C. China (South) - ILI Surveillance During week 9, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.4%, higher than last week (3.0%), as well as the corresponding weeks of 2014 and 2015 (2.9% and 2.7% respectively) (Figure 8). In South China, influenza B was the predominant type of influenza detected (54.3%). Of the influenza B subtypes, B Victoria was the most common (62.3%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI decreased from 3,148 (over 5.5 working days) in week 8 to 3,001 (over 5.5 working days) in week 9 (Figure 9). The proportion of patients with influenza-like illness (ILI) among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=249) in the community was 66.7% in the past 4 weeks. Of specimens that tested positive for influenza in February 2016, 61.1% were positive for influenza B, 22.7% for influenza A (H1N1) pdm09, and 16.2% for influenza A (H3N2). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update | 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2011-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, as of week 9, the number of ILI cases reported is higher than the previous weeks in Fiji, Guam, Kiribati and New Caledonia. (Figure 10) Figure 10: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_03_07_surveillance_update_258.pdf? ua=1 Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 1 March 2016 Virological Surveillance Summary Table 1: Predominant influenza viruses, Western Pacific Region, 2015 to week 7 2016 Year Week Predominant viruses 2015 1-9 A (H3) 10-16 B (Yamagata lineage), B (lineage not determined) 17-19 B (Yamagata lineage), A (H3) 20-37 A (H3) 38-42 A (H3), B (lineage not determined) 43-51 Influenza virus activity is low in all subtypes 52-53 A(H3), A(H1N1)pdm09 2016 1-7 A(H1N1)pdm09 The number of specimens provided to FluNet by each of the Western Pacific Region countries that reported between week 1 and week 7, and proportion of all specimens contributed by each country is presented in the table below. Table 2: Countries providing specimens for FluNet, Western Pacific Region, weeks 1 to 7, 2016 Country Total % Cambodia 149 6 Lao People's Democratic Republic 428 16 Philippines 124 5 Republic of Korea 1519 57 Singapore 397 15 Viet Nam 32 1 Figure 1: Number of specimens positive for influenza by subtype and week, Western Pacific Region, 2015-16 (accessed 1 March 2016) Influenza Situation Update | 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) In week 6 2016, ILI activity increased to a level above seasonal peaks observed since 2011. The proportion of hospital visits that were for ILI at national sentinel hospitals in north China in week 6 was 4.6%, compared to 3% in week 5 of 2016, and 3.5% and 2.8% in the corresponding week of 2014 and 2015 respectively (Figure 2). Mongolia In week 7, 2016, ILI activity in Mongolia is increasing in line with seasonal trend (Figure 3). Republic of Korea In week 8, 2016, the rate of ILI patient visits to sentinel physicians (46.1/1,000 outpatients) followed the seasonal trend of previous years (2012-2015) and was above baseline (11.3/1,000 outpatients) (Figure 4). China (North) Figure 1: Percentage of visits for ILI at sentinel hospitals, 2011-2016 (Source: China National Influenza Center) Mongolia Figure 2: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Influenza Situation Update | 3 Republic of Korea Figure 3: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Sentinel influenza surveillance Japan As of 24 February 2016, the number of influenza cases reported weekly, per sentinel hospital site increased in line with previous seasons peaks. Figure 4: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Influenza Situation Update | 4 Countries/areas in the tropical zone In weeks 1 to 8 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 8, overall influenza activity remained at a high level. The average consultation rate for influenza- like illness (ILI) among sentinel general outpatient clinics was 9.0 ILI cases per 1,000 consultations, which was lower than 10.6 per 1,000 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 47.6 ILI cases per 1,000 consultations, which was lower than 54.7 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 8 which tested positive for seasonal influenza viruses was 24.2%, slightly higher than that recorded in the previous week (22.9%). Of all respiratory specimens tested in week 8, 1,185 (24.2%) tested positive for seasonal influenza viruses, including; 771 (15.7%) influenza A (H1), 49 (1.0%) influenza A (H3), 323 (6.6%) influenza B and 42 (0.9%) influenza C. China (South) - ILI Surveillance During week 6, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 5.6%, higher than last week (4.2%), as well as the corresponding weeks of 2014 and 2015 (4.1% and 2.9% respectively) (Figure 8). In South China, influenza A was the predominant type of influenza detected (78.9%). Of the influenza A subtypes, A (H1N1) pdm09 was the most common (95.5%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI decreased from 3,740 (over 3.5 working days) in week 6 to 3,174 (over 5.5 working days) in week 7 (Figure 9). The proportion of patients with influenza-like illness (ILI) among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=244) in the community was 60.7% in the past 4 weeks. Of specimens that tested positive for influenza in January 2016, 45% were positive for influenza B, 28.9% for influenza A (H3N2), and 26.1% for influenza A (H1N1) pdm09. Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Influenza Situation Update | 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2011-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, as of week 6, the number of ILI cases reported is higher than the previous weeks in Fiji, Northern Mariana Islands and Palau. (Figure 10) Figure 10: Reported cases of influenza-like illness (red line) in Pacific Island Countries, 2015–2016 Influenza Situation Update | 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_02_08_surveillance_update_256.pdf?ua=1 Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY

Bi-weekly Influenza Situation Update 16 February 2016 Virological Surveillance Summary In the Western Pacific Region, the following influenza viruses predominated: Table1. Countries providing specimens for FluNet from week 1 to week 5 2016. Country Total % Cambodia 22 1.2 Lao People's Democratic Republic 201 11.1 Philippines 124 6.9 Republic of Korea 1158 64.3 Singapore 297 16.5 Countries providing specimens for FluNet reporting from the Western Pacific Region in 2016 include Cambodia, Lao PDR, Philippines, the Republic of Korea and Singapore. From week 1 to week 5 of 2016 64% of influenza specimens provided to FluNet were from Korea (n=1158), 16.5% from Singapore (n=297), 11.1% from Lao PDR (n=201), 6.9% from Philippines (n=124) and 1.2% from Cambodia (n=22). Figure 1: Number of specimens positive for influenza by subtype in Western Pacific Region (Source: FluNet (www.who.int/flunet), accessed 16 February 2016) Year Week Predominant viruses 2015 1-9 A (H3) 10-16 B (Yamagata lineage), B (lineage not determined) 17-19 B (Yamagata lineage), A (H3) 2016 20-37 38-42 43-51 52-53 1-5 A (H3) A (H3), B (lineage not determined) Influenza virus activity is low in all subtypes A(H3), A(H1N1)pdm09 A(H1N1)pdm09 Bi-weekly Influenza Situation Update| 2 Influenza surveillance summary Influenza surveillance in the WHO Western Pacific Region is based on outpatient and inpatient sentinel surveillance systems. Case definitions, populations under surveillance and data formats differ among these countries. This influenza surveillance summary includes countries where routine surveillance is conducted and information is available from syndromic surveillance systems for Influenza-like-illness (ILI) and Severe Acute Respiratory Infections (SARI). The WHO surveillance case definition for ILI is an acute respiratory infection with a measured fever of ≥38oC and cough, with symptom onset within the last 10 days. For SARI, it is an acute respiratory infection with a history of fever or measured fever of ≥38oC and cough, with symptom onset within the last 10 days and requires hospitalization. Countries in the temperate zone of the Northern Hemisphere In most countries within the temperate zone of the Northern Hemisphere, ILI and influenza activity remained at low levels. Outpatient ILI Surveillance China (North) In week 3, 2016, ILI activity remained lower than the general seasonal trend observed in the majority of previous years (2011 –2015). Proportion of hospital visits that were ILI at national sentinel hospitals in north China was 3.6%, higher than last week (3.3%), same as the same week in 2015 and lower than the same week in 2014 (3.6% and 4.2% respectively) (Figure 2). Mongolia In week 4, 2016, ILI activity in Mongolia is increasing in line with seasonal trend (Figure 3). Republic of Korea In week 6, 2016, the rate of ILI patient visits to sentinel physicians (41.3/1,000 outpatients) followed the seasonal trend of previous years (2012-2015) and was above baseline (11.3/1,000 outpatients) (Figure 4). China (North) Figure 2: Percentage of visits for ILI at sentinel hospitals, 2011-2016 (Source: China National Influenza Center) Mongolia Figure 3: Proportion of outpatients that were ILI (per 10,000 people), 2013-2016 (Source: Mongolia National Influenza Center) Bi-weekly Influenza Situation Update| 3 Republic of Korea Sentinel influenza surveillance Japan As of 3 February 2016 in Japan, the number of influenza cases reported weekly per hospital sentinel site followed the known seasonal trend (2005-2015), with case numbers remaining low (Figure 5). Figure 5: Number of influenza cases reported weekly per sentinel hospital site, Japan 2006-2016 (Source: Japan National Institute of Infectious Diseases) Figure 4: Weekly proportion of ILI visits per 1,000 patients 2012-2016 (Source: Korean Centre for Disease Control and Prevention) Bi-weekly Influenza Situation Update| 4 Countries/areas in the tropical zone In week 1-6 of 2016, ILI or Acute Respiratory Infection (ARI) activity followed previous seasonal trends in countries/areas in the tropical zone. Outpatient Surveillance Hong Kong (China) - ILI Surveillance During week 6, overall influenza activity has continued to increase. The average consultation rate for influenza-like illness (ILI) among sentinel general outpatient clinics (GOPCs) was 7.5 ILI cases per 1,000 consultations, which was higher than 5.6 per 1,000 recorded in the previous week (Figure 6). The average consultation rate for ILI among sentinel private doctors was 53.4 ILI cases per 1,000 consultations, which was higher than 40.1 per 1,000 recorded in the previous week (Figure 7). The percentage of respiratory specimens in week 6 which tested positive for seasonal influenza viruses was 16.34%, which was higher than recorded in the previous week (9.25%). Of all respiratory specimens tested in week 6, 6643 (16.34%) were tested positive for seasonal influenza viruses, including 406 (10.32%) influenza A(H1), 53 (1.35%) influenza A(H3), 152 (3.86%) influenza B and 32 (0.81%) influenza C. China (South) - ILI Surveillance During week 3, the percentage of outpatient or emergency visits for ILI at national sentinel hospitals in south China was 3.4%, higher than last week (3.2%) (Figure 8). In South China, influenza A was the predominant type of influenza detected (74.5%). Of the influenza A subtypes, A (H1N1)pdm09 was the most common (86%). Singapore – ARI Surveillance The average daily number of patients seeking treatment in the polyclinics for ARI increased from 3,111 (over 5.5 working days) in week 4 to 3,125 (over 5.5 working days) in week 5 (Figure 9). The proportion of patients with influenza-like illness (ILI) among the polyclinic attendances for ARI remained low at approximately 1%. The overall prevalence of influenza among ILI samples (n=245) in the community was 62.0% in the past 4 weeks. Of the specimens tested positive for influenza in January 2016, these were positive for influenza B (45.0%), influenza A(H3N2) (28.9%), and influenza A (H1N1)pdm09 (26.1%). Hong Kong (China) - ILI Surveillance Figure 6: ILI consultation rates at sentinel general outpatient clinics, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Figure 7: ILI consultation rates at sentinel private doctors, Hong Kong 2012-2016 (Source: Hong Kong Centre for Health Protection) Bi-weekly Influenza Situation Update| 5 China (South) - ILI Surveillance Figure 8: Percentage of visits due to ILI at national sentinel hospitals in South China, 2011-2016 (Source: China National Influenza Center) Singapore - ARI Surveillance Figure 9: Average daily polyclinic attendances for Acute Respiratory Infection, Singapore 2015-2016 (Source: Singapore Ministry of Health) Countries in the temperate zone of the southern hemisphere Influenza surveillance data from Australia and New Zealand is reported during their influenza season and will not be updated in this report unless unusual activity is apparent. Pacific Island Countries and Areas (PICs)- ILI Surveillance In the Pacific Island Countries and Areas, as of week 5, the number of ILI cases reported is higher than the previous weeks in American Samoa, Federated States of Micronesia, Fiji, Marshall Islands, Palau, Samoa, and Solomon Islands (Figure 10). Figure 10: Reported cases of influenza-like illness (ILI) in PICs (red line), 2015–2016 Bi-weekly Influenza Situation Update| 6 Global influenza situation updates Epidemiological update: http://www.who.int/influenza/surveillance_monitoring/updates/2016_02_08_surveillance_update_256 .pdf?ua=1 Virological update: http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport/en/ Global update: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance/ Others: Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere influenza season http://www.who.int/influenza/vaccines/virus/recommendations/2016_south/en/ Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for potential use in human vaccines http://www.who.int/influenza/vaccines/virus/characteristics_virus_vaccines/en/ 4th WHO Informal Consultation on Improving Influenza Vaccine Virus Selection http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport Video on influenza on WHO's YouTube Channel Arabic: https://www.youtube.com/watch?v=PxW6Pg1AnwI Chinese: https://www.youtube.com/watch?v=xW9gDKEPitQ English: https://www.youtube.com/watch?v=yhhJfT86Bgg French: https://www.youtube.com/watch?v=8mo8rWWJZkc Russian: https://www.youtube.com/watch?v=XQO6nbkKUWQ Spanish: https://www.youtube.com/watch?v=qXr75cKxwTY