Male circumcision programmes in Kenya: lessons from the Kenya AIDS Indicator Survey 2007

Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412 Research 642 Male circumcision programmes in Kenya: lessons from the Kenya AIDS Indicator Survey 2007 Zebedee Mwandi,a Rebecca Bunnell,a Peter Cherutich,b Jonathan Mermin,a Andrea A Kim,c Anthony Gichangi,a Patrick Mureithi,d Timothy A Kellogg,e Tom Oluoch,a James Muttunga,f Carol Ngare,b Evelyn Kimc & Reinhard Kaisera Introduction Of an estimated 33.4 million people living with human immunodeficiency virus (HIV) infections worldwide, ap- proximately 22.4 million live in sub-Saharan Africa and, of these, 1.5 million live in Kenya.1 Most HIV transmission in sub-Saharan Africa and Kenya is heterosexual. In the past two decades, observational studies have provided evidence that male circumcision has a protective effect against HIV infection and sexually transmitted infections in general.2,3 In addition, three randomized controlled trials indicated that male circumcision reduces the acquisition rate for HIV infection by approximately 60%.4–6 Consequently, the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) recommended that countries include male circumcision as part of HIV preven- tion interventions and expand its implementation, priori- tizing areas with a low male circumcision rate and a high prevalence of HIV infection.7 Kenya’s population comprises over 40 ethnic groups, many of which have a cultural tradition of male circumcision. However, despite a high rate of migration from rural to urban areas and the resulting heterogeneous mixing of people with different ethnic and cultural practices, individuals’ cultural and religious practices, including their attitude to circumcision, tend to remain unchanged. The 2003 Kenya Demographic Health Survey estimated that 84% of men in the country were circumcised: the rate ranged from 46.4% in Nyanza province to 100% in North Eastern Province.8 Optimizing the expansion of male circumcision services depends on having nationally representative data on the size of the population and the distribution of uncircumcised men and on their demographic characteristics and sexual behaviour. Suitable data only became available with the 2007 Kenya AIDS Indicator Survey, which was used by the Kenyan Ministry of Public Health and Sanitation to develop a national strategy for male circumcision in 2009.9 The aim was to circumcise 80% of all eligible men aged 15 to 49 years between 2009 and 2013 and, consequently, to avert an estimated 100 000 HIV infections over 10 years.10 The male circumcision strategy targets men in four provinces with relatively large male adult populations where traditionally few men are circumcised (i.e. Nairobi, Nyanza, Rift Valley and Western Province).9 The strategy involves a phased approach over more than 10 years in which progressively younger males are circumcised, start- ing with men aged 15 years and older in regions with a high prevalence of HIV infection and a low circumcision rate and concluding with infant circumcision, where acceptable (personal communication, Kenyan Ministry of Public Health and Sanitation). Objective To provide guidance for male circumcision programmes in Kenya by estimating the population of uncircumcised men and investigating the association between circumcision and infection with the human immunodeficiency virus (HIV), with particular reference to uncircumcised, HIV-uninfected men. Methods Data on men aged 15 to 64 years were derived from the 2007 Kenya AIDS Indicator Survey, which involved interviews and blood collection to test for HIV and herpes simplex virus 2 (HSV-2). The prevalence of HIV infection and circumcision in Kenyan provinces was calculated and the demographic characteristics and sexual behaviour of circumcised and uncircumcised, HIV-infected and HIV-uninfected men were recorded. Findings The national prevalence of HIV infection in uncircumcised men was 13.2% (95% confidence interval, CI: 10.8–15.7) compared with 3.9% (95% CI: 3.3–4.5) among circumcised men. Nyanza province had the largest estimated number of uncircumcised, HIV-uninfected men (i.e. 601 709), followed by Rift Valley, Nairobi and Western Province, respectively, and most belonged to the Luo ethnic tribe. Of these men, 77.8% did not know their HIV status and 33.2% were HSV-2-positive. In addition, 65.3% had had unprotected sex with a partner of discordant or unknown HIV status in the past 12 months and only 14.7% consistently used condoms with their most recent partner. However, only 21.8% of the uncircumcised, HIV-uninfected men aged 15 to 19 years were sexually active. Conclusion The Kenyan male circumcision strategy should focus on the provinces with the highest number of uncircumcised, HIV-uninfected men and target young men before or shortly after sexual debut. a Center for Global Health, US Centers for Disease Control and Prevention, PO Box 606, Village Market, Nairobi, 00621, Kenya. b National AIDS and STI Control Program, Ministry of Public Health and Sanitation, Nairobi, Kenya. c Center for Global Health, US Centers for Disease Control and Prevention, Atlanta, United States of America (USA). d National AIDS Control Council, Government of Kenya, Nairobi, Kenya. e San Francisco Department of Health, San Francisco, USA. f Kenya Medical Research Institute, Nairobi, Kenya. Correspondence to Zebedee Mwandi (e-mail: zmwandi@ke.cdc.gov). (Submitted: 24 October 2011 – Revised version received: 3 April 2012 – Accepted: 4 April 2012 – Published online: 19 June 2012 ) R search Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412 643 Research Male circumcision in KenyaZebedee Mwandi et al. We conducted an in-depth analysis of national male circumcision data from the 2007 Kenya AIDS Indicator Survey with the aim of: (i) describing the preva- lence of male circumcision in Kenya and the association between the prevalence of circumcision and the prevalence of HIV infection; (ii) describing the de- mographic characteristics and sexual be- haviour of circumcised, uncircumcised, and uncircumcised HIV-uninfected men in Kenya; (iii) estimating the num- ber of circumcised, uncircumcised, and uncircumcised HIV-uninfected men in Kenya; and (iv) deriving implications for male circumcision planning in Kenya. Although the national circumcision strategy targets both HIV-infected and HIV-uninfected men,9 our analysis paid particular attention to uncircumcised, HIV-uninfected men since there is little evidence that circumcising uncir- cumcised HIV-infected men reduces the risk of HIV transmission to sexual partners.11 Methods The 2007 Kenya AIDS Indicator Survey involved a representative sample of households from all eight provinces in Kenya and was carried out between August and December 2007.12 It was designed to provide national and pro- vincial data on the sociodemographic, behavioural and biological correlates of HIV infection.13 All individuals aged 15 to 64 years who were either usually resi- dent in the selected households or visit- ing the household on the night before the survey were eligible to participate. Interviewers obtained information on the participants’ demographic charac- teristics and sexual behaviour using a structured questionnaire. In addition, a venous blood sample was taken to test for the presence of HIV or herpes sim- plex virus 2 (HSV-2) infection. All those who participated in the interview and gave a blood sample provided informed consent. The study was approved by the Kenya Medical Research Institute’s ethical review committee and the insti- tutional review board of the Centers for Disease Control and Prevention in the United States of America (USA). The interviewers obtained informa- tion on: (i) male circumcision, including whether, where and by whom it had been performed and age at circumci- sion; (ii) self-reported HIV status, based on the results of previous HIV testing; (iii) consistent condom use with the most recent sexual partner in the last 12 months, where consistent use was defined as using a condom each time the respondent had sexual intercourse with this partner; (iv) the number of sexual partners of unknown or discordant HIV status, based on the self-reported HIV status of partners, in the last 12 months; and (v) unprotected sex with a partner of unknown or discordant HIV status during at least one of the three most recent sex acts in the last 12 months. In- dividuals who performed male circum- cision were classified as either medical practitioners, traditional practitioners or home health workers. No physical examination was conducted to verify circumcision. Laboratory tests were performed by the Kenya National Public Health Laboratories12 and quality assurance was carried out at the laboratory of the Centers for Disease Control and Preven- tion and the Kenya Medical Research Institute in Nairobi. The Vironostika HIV-1/2 test (Bio-Mérieux Diagnos- tics, Marcy l’Etoile, France) was used to screen for HIV infection and all samples that tested positive were confirmed using the Murex HIV.1.2.O enzyme immunoassay (Abbott Laboratories, Abbott Park, USA). Samples that gave discordant results on the two tests were retested using the two assays and, if there were two sets of discordant results, the Roche HIV DNA version 1.5 polymerase chain reaction test (Hoffmann La Roche, Basel, Switzerland) was performed. All samples that tested positive for HIV and 5% of those that tested negative were retested at the quality assurance laboratory using the same procedure. Testing for HSV 2 was carried out using the Kalon enzyme immunoassay (Kalon Biological Limited, Guildford, United Kingdom of Great Britain and Northern Ireland). All samples that tested posi- tive were retested using the Kalon test by a second laboratory technician. For quality control, all samples that tested positive for HSV 2, 5% of those that tested negative and all those that gave indeterminate results were retested at the quality assurance laboratory using the same procedure. Samples that gave discordant results at the two laboratories were reported as indeterminate. We calculated the number of men in Kenya who had not been circumcised from estimates of the population and of the prevalence of circumcision and HIV infection in each province. We used the 1999 Kenyan Population and Household Census to estimate the size of the adult population.14 However, because data from the 2007 Kenya AIDS Indicator Survey on the number of uncircumcised men in some provinces included fewer than 25 observations, we calculated uncertainty bounds for the population estimates based on 95% confidence in- tervals (CIs) derived from survey data. All analyses were performed using the procedures for surveys in SAS software version 9.2 (SAS Institute Inc., Cary, USA). The analysis took into account the stratified cluster design of the survey and each response was weighted to take its sampling probability into account and to adjust for the nonresponse rate. Results Of the 19 840 individuals eligible to participate in the survey, 91% were in- terviewed and 80% gave blood samples. In total, 8883 were men. Of these, 7701 (86.7%) participated in the interview: 6586 (74.1%) reported being circum- cised and 1092 (12.3%) reported being uncircumcised, whereas 23 (0.26%) did not report their circumcision status. Of the 1092 uncircumcised men, 979 (89.7%) were tested for HIV infection during the survey. The overall prevalence of HIV infection in uncircumcised men was 13.2% compared with 3.9% in circum- cised men Table 1. The prevalence was substantially higher among uncircum- cised men aged 25 to 54 years than in those aged 15 to 24 years and peaked among men aged 35 to 44 years at 30.2% (Fig. 1). Table 2 shows the estimated num- ber of men aged 15 to 64 years in the eight provinces in Kenya who were or were not circumcised or infected with HIV. The number of HIV-uninfected men who were uncircumcised at the time of the survey was estimated to be around 1.2 million, which corresponded to 13% of the total male population in Kenya aged 15 to 64 years. Nyanza and Rift Valley Provinces had the highest estimated number of uncircumcised, HIV-uninfected men (601 709 and 235 688, respectively), followed by Nai- robi Province with 135 271 and Western Province with 113 692 (Table 2). These four provinces accounted for nearly 90% of all uncircumcised, HIV-uninfected men in the country. Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412644 Research Male circumcision in Kenya Zebedee Mwandi et al. Table 1. Circumcised and uncircumcised men aged 15–64 years, Kenya AIDS Indicator Survey 2007 Variable Circumcised men (n = 6 586) Uncircumcised men (n = 1 092) No. Weighted %a (95% CI) No. Weighted %a (95% CI) Total 6586 3.9 (3.3–4.5) 1092 13.2 (10.8–15.7) Age group, years 15–24 2008 31.6 (30.0–33.3) 505 48.8 (45.2–52.4) 25–34 1654 24.5 (23.1–25.9) 227 20.1 (17.3–22.8) 35–44 1249 19.0 (17.8–20.2) 161 14.4 (12.1–16.7) 45–54 953 13.8 (12.9–14.7) 125 10.2 (8.3–12.1) 55–64 722 11.0 (10.1–11.9) 74 6.6 (4.8–8.3) Total 6586 100 (NA) 1092 100 (NA) Province Nairobi 792 8.9 (7.3–10.5) 133 10.2 (5.7–14.7) Central 1072 16.0 (14.4–17.7) 49 4.3 (2.6–6.0) Coast 794 8.6 (7.3–9.9) 28 1.5 (0.8–2.3) Eastern 1243 20.6 (18.0–23.3) 52 4.5 (2.4–6.6) North-Eastern 325 2.0 (1.6–2.4) 9 0.3 (0.0–0.6) Nyanza 533 8.6 (7.2–10.1) 566 52.9 (46.3–59.4) Rift Valley 970 23.0 (20.3–25.6) 120 16.7 (12.2–21.2) Western 857 12.2 (10.6–13.8) 135 9.7 (5.2–14.1) Total 6586 100 (NA) 1092 100 (NA) Area of residence Rural 4880 77.2 (74.1–80.3) 836 79.8 (74.2–85.4) Urban 1706 22.8 (19.7–25.9) 256 20.2 (14.6–25.8) Total 6586 100 (NA) 1092 100 (NA) Educational level No primary 605 6.5 (5.4–7.6) 54 6.4 (3.7–9.1) Incomplete primary 1696 27.2 (25.3–29.1) 429 41.1 (36.5–45.6) Complete primary 1580 24.6 (23.2–26.1) 259 23.5 (20.4–26.5) Secondary or higher 2705 41.7 (39.3–44.1) 350 29.0 (24.8–33.3) Total 6586 100 (NA) 1092 100 (NA) Marital status Never married or cohabited 2301 35.3 (33.6–37.0) 489 46.9 (43.1–50.8) Currently married or cohabiting 3918 58.8 (57.0–60.7) 551 48.6 (44.9–52.3) Separated or divorced 288 4.5 (3.9–5.1) 34 2.8 (1.6–3.9) Widowed 79 1.3 (1.0–1.7) 18 1.7 (0.8–2.5) Total 6586 100 (NA) 1092 100 (NA) Ethnic tribe Embu 101 1.6 (0.9–2.3) 2 0.2 (0.0–0.5) Kalenjin 545 11.0 (8.8–13.1) 41 5.9 (2.4–9.3) Kamba 809 13.6 (10.5–16.8) 6 0.8 (0.0–1.8) Kikuyu 1590 25.2 (22.6–27.7) 54 4.8 (2.8–6.9) Kisii 509 8.2 (6.8–9.5) 5 0.4 (0.0–0.8) Luhya 1161 17.0 (15.0–18.9) 81 5.7 (2.1–9.2) Luo 147 2.3 (1.6–2.9) 739 66.7 (60.5–72.9) Masai 68 2.0 (0.7–3.3) 3 0.4 (0.0–0.8) Meru 438 7.5 (6.3–8.7) 32 3.1 (1.5–4.8) Mijikenda 448 5.0 (4.0–6.0) 0 Somali 383 2.4(2.0–2.9) 5 0.2 (0.0–0.4) Taita/Taveta 110 1.0 (0.7–1.3) 2 0.1 (0.0–0.2) Swahili 10 0.1 (0.0–0.1) 0 Other 267 3.2 (2.2–4.2) 122 11.7 (7.3–16.1) Total 6586 100 (NA) 1092 100 (NA) (continues. . .) 645Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412 Research Male circumcision in KenyaZebedee Mwandi et al. Circumcised versus uncircumcised men The median age of the 6586 circumcised men included in the survey was 32 years (interquartile range, IQR: 23–45) and their median age at the time of circum- cision was 13 years (IQR: 10–16 years). The median time since circumcision was 20 years (IQR: 10–32). Overall, 83.9% (95% CI: 82.5–85.3) were circumcised under the age of 25 years and 1.7% reported being circumcised at 1 year of age or younger. Most circumcised men lived in rural areas, had completed at least primary education, were currently married or cohabiting with a partner and had never been tested for HIV (Table 1). More of these men belonged to the Kikuyu ethnic tribe than to any other ethnic tribe. Nearly one quarter Variable Circumcised men (n = 6 586) Uncircumcised men (n = 1 092) No. Weighted %a (95% CI) No. Weighted %a (95% CI) Self-reported HIV status Never tested or unknownb 4833 76.2 (74.6–77.8) 791 75.7 (71.8–79.5) Negative 1530 23.3 (21.7–24.9) 239 22.0 (18.2–25.9) Positive 29 0.5 (0.3–0.7) 27 2.3 (1.3–3.3) Total 6392 100 (NA) 1057 100 (NA) HSV-2 infection No 4355 75.8 (74.3–77.4) 546 59.3 (55.6–63.1) Yes 1320 24.2 (22.6–25.7) 396 40.7 (36.9–44.4) Total 5675 100 (NA) 942 100 (NA) Consistent condom use with most recent partner in the last 12 months Yes 601 12.3 (11.1–13.5) 124 16.1 (12.7–19.4) No 4389 87.7 (86.5–88.9) 633 83.9 (80.6–87.3) Total 4990 100 (NA) 757 100 (NA) Number of sexual partners of unknown or discordant HIV status in the last 12 months 0 1037 23.4 (21.8–25.0) 136 20.2 (15.5–24.9) 1 2962 66.8 (65.1–68.5) 423 63.2 (58.1–68.2) 2 371 8.5 (7.5–9.5) 92 12.9 (9.9–15.8) 3 or more 56 1.3 (0.9–1.7) 29 3.8 (2.3–5.3) Total 4426 100 (NA) 680 100 (NA) Unprotected sex in the last 12 monthsc With partner of unknown or discordant status 3143 65.0 (62.9–67.0) 463 63.1 (56.8–69.3) With partner of concordant status 1137 23.3 (21.5–25.1) 156 21.1 (17.0–25.2) Did not have unprotected sex 566 11.7 (10.5–13.0) 118 15.8 (12.4–19.3) Total 4846 100 (NA) 737 100 (NA) CI, confidence interval; HIV, human immunodeficiency virus; HSV-2, herpes simplex virus 2; NA, not applicable. a Each man’s response was weighted to take its sampling probability into account and to adjust for the nonresponse rate. b In total, 74 circumcised men and 26 uncircumcised men had been tested but did not know their HIV status. c An individual was classified as having had unprotected sex in the last 12 months if he had unprotected sex during at least one of the three most recent sex acts in the last 12 months. Fig. 1. Prevalence of HIV infection among men aged 15–64 years, by circumcision status and age, Kenya AIDS Indicator Survey 2007 Circumcised, HIV-infected men Uncircumcised, HIV-infected men Pe rc en ta ge H IV -p os iti ve 40 35 30 25 20 15 10 5 0 Age group (years) 15–24 25–34 35–44 45–54 55–64 Note: The bars represent 95% confidence intervals. (. . .continued) Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412646 Research Male circumcision in Kenya Zebedee Mwandi et al. had an HSV-2 infection. In total, 87.7% of sexually-active, circumcised men reported that they had not consistently used a condom with their most recent partner in the last 12 months, 76.6% had had at least one partner of unknown or discordant HIV status in the last 12 months and 65.0% reported that they had unprotected sex with a partner of unknown or discordant HIV status in the last 12 months. Among circumcised men, 45.5% (95% CI: 43.0–48.1) reported having been circumcised at a health facility, whereas 52.4% (95% CI: 49.9–54.9) were circumcised at home (data not shown). Only 2.1% (95% CI: 1.5–2.7) were cir- cumcised at another location or did not know who circumcised them. Of those circumcised at home, 21.8% (95% CI: 19.3–24.3) were circumcised by a home health worker or medical practitioner and 77.7% (95% CI: 75.2–80.2) were circumcised by a traditional practitio- ner. Overall, 57.1% (95% CI: 54.8–59.4) had been circumcised by a health worker or medical practitioner, irrespective of whether it took place at home or at a health facility, whereas 42.7% (95% CI: 40.2–44.7) had been circumcised by a traditional practitioner. The median age of the 1092 uncir- cumcised men included in the survey was 26 years (IQR: 18–40). The majority lived in rural areas and almost half did not complete primary education (Table 1). In addition, almost half of all uncircumcised men were unmarried, the majority came from the Luo ethnic tribe and most had never been tested for HIV. Overall, 40.7% were infected with HSV 2. Among sexu- ally-active, uncircumcised men, 83.9% reported that they did not consistently use a condom with their most recent partner, 79.8% had at least one partner of unknown or discordant HIV status in the last 12 months and 63.1% had unpro- tected sex with a partner of unknown or discordant status in the last 12 months. Compared with circumcised men, uncircumcised men were younger, less well educated, less likely to be married or cohabitating with a partner and more likely to be infected with HSV 2 (P < 0.0001 for all; Table 1). Uncircum- cised men were more likely to report consistent condom use with their most recent partner in the last 12 months (P = 0.0212) and having had two or more partners of unknown or discordant HIV status in the last 12 months (P = 0.0012). They were less likely to report unpro- Ta bl e 2. M al e po pu la tio n ag ed 1 5– 64 ye ar s i n Ke ny a, b y p ro vi nc e, ci rc um cis io n st at us a nd H IV in fe ct io n st at us , 2 00 7 Pr ov in ce No . o f m e n ag ed 1 5– 64 ye ar sa % m al e cir cu m cis io n ra te b No . o f cir cu m cis ed m en a ge d 15 –6 4 ye ar s No . o f un cir cu m cis ed m en a ge d 15 –6 4 ye ar s HI V in fe ct io n in u nc irc um cis ed m en a ge d 15 –6 4 ye ar sc No . o f un cir cu m cis ed , H IV - in fe ct ed m en a ge d 15 –6 4 ye ar s Un cir cu m cis ed , H IV -u ni nf ec te d m en a ge d 15 –6 4 ye ar s No . o f H IV -in fe ct ed m en / t ot al n o. d % (9 5% CI ) No . Un ce rt ai nt y b ou nd e N ai ro bi 1 00 9 00 0 83 .2 83 9 48 8 16 9 51 2 21 /1 22 20 .2 (1 2. 8– 27 .5 ) 34 2 41 13 5 27 1 12 2 89 6– 14 7 81 4 Ce nt ra l 1 16 0 00 0 95 .5 1 10 7 80 0 52 2 00 0/ 43 0 (N A) 0 N A N A Co as t 75 9 00 0 97 .0 73 6 23 0 22 7 70 5/ 24 15 .3 (6 .9 –2 3. 6) 3 46 1 19 3 09 17 3 96 –2 1 19 9 Ea st er n 1 38 0 00 0 96 .3 1 32 8 94 0 51 0 60 1/ 49 0. 9 (0 .0 –2 .6 ) 51 1 50 5 49 49 7 32 –5 1 06 0 N or th - Ea st er n 36 1 00 0 97 .3 35 1 25 3 9 74 7 1/ 9 7. 2 (0 .0 –1 8. 5) 69 2 9 05 5 7 94 4– 9 74 7 N ya nz a 1 40 8 00 0 48 .2 67 8 65 6 72 9 34 4 96 /5 01 17 .3 (1 3. 3– 21 .2 ) 12 7 63 5 60 1 70 9 57 2 53 5– 63 2 34 1 Ri ft Va lle y 2 24 2 00 0 88 .7 1 98 8 65 4 25 3 34 6 12 /1 12 7. 0 (2 .0 –1 1. 9) 17 6 58 23 5 68 8 22 3 19 8– 24 8 27 9 W es te rn 1 00 0 00 0 87 .8 87 8 00 0 12 2 00 0 8/ 11 9 6. 8 (2 .0 –1 1. 6) 8 30 8 11 3 69 2 10 7 84 8– 11 9 56 0 To ta l 9 31 9 00 0 85 .0 7 90 9 02 1 1 40 9 99 7 14 4/ 97 9 13 .2 (1 0. 8– 15 .7 ) 18 6 12 0 1 22 3 87 7 1 18 8 62 7– 1 25 7 71 7 CI , c on fid en ce in te rv al ; H IV , h um an im m un od efi ci en cy v iru s; N A, n ot a pp lic ab le . a E st im at ed u sin g da ta fr om th e Ke ny an 1 99 9 Po pu la tio n an d Ho us eh ol d Ce ns us . b D er iv ed fr om th e Ke ny a AI D S In di ca to r S ur ve y 20 07 . c D er iv ed fr om th e Ke ny a AI D S In di ca to r S ur ve y 20 07 . d T he n um be r o f H IV -in fe ct ed , u nc irc um ci se d m en a nd th e to ta l n um be r o f u nc irc um ci se d m en w er e th os e in cl ud ed in th e Ke ny a AI D S In di ca to r S ur ve y 20 07 fo r e ac h pr ov in ce . e T he u nc er ta in ty b ou nd s w er e ba se d on th e 95 % c on fid en ce in te rv al s f ro m th e Ke ny a AI D S In di ca to r S ur ve y 20 07 . Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412 647 Research Male circumcision in KenyaZebedee Mwandi et al. tected sex and unprotected sex with a partner of unknown or discordant HIV status in the last 12 months (P = 0.0087). Although some sociodemographic differences between circumcised and uncircumcised men, such as marital status, were influenced by the differ- ence in median age between the groups, some differences remained statistically significant even when age was taken into account. For example, circum- cised men aged 15 to 34 years were less likely than uncircumcised men of the same age to be from Nyanza province (9.4% [95% CI: 7.7–11.0] versus 49.3% [95% CI: 42.2–56.4], respectively), to belong to the Luo ethnic tribe (2.4% [95% CI: 1.6–3.1] versus 64.0% [95% CI: 57.2–70.7], respectively) and to have an HSV-2 infection (12.1% [95% CI: 10.7–13.5] versus 26.4% [95% CI: 22.0–30.9], respectively). Uncircumcised, HIV-uninfected men Table 3 shows the sociodemographic characteristics and reported sexual behaviour of the 835 uncircumcised, HIV-uninfected men in the survey. These men are representative of the pri- ority target group for voluntary medical male circumcision in Kenya. The median age of this group was 26 years (IQR: 18–40): 55.0% were aged under 25 years and 72.5% were aged under 35 years (Table 3). Overall, 80.2% lived in rural areas and 93.7% had been educated to primary school level at least. In addi- tion, 52.5% were neither married nor cohabiting with a partner at the time of the survey. Among those who were married or cohabitating, 13.7% (95% CI: 9.9–17.6) were in a polygamous marriage. In total, 63.1% were from the Luo ethnic tribe, whereas 5.5% and 6.7% were from the Luhya and Kalenjin ethnic tribes, respectively. The Kikuyu ethnic tribe, a community in which circumci- sion predominates, accounted for 5.8%. Of the 835 uncircumcised, HIV- uninfected men, 22 (2.6%) did not respond to the question on HIV status, and 77.8% reported that they did not know their HIV status (Table 3). How- ever, 33.2% had HSV-2 infections. In addition, 63.4% (95% CI: 58.8–68.1) of those aged 15 to 64 years and 21.8% (95% CI: 16.2–27.4) of those aged 15 to 19 years were sexually active. Of the sexually-active, uncircumcised, HIV- uninfected men aged 15 to 64 years, Table 3. Uncircumcised, HIV-uninfected men aged 15–64 years, Kenya AIDS Indicator Survey 2007 Variable Uncircumcised, HIV-uninfected men (n = 835) No. Weighted %a (95% CI) Age group, years 15–24 439 55.0 (51.2–58.9) 25–34 155 17.5 (14.2–20.8) 35–44 94 11.1 (8.9–13.4) 45–54 86 9.2 (7.2–11.1) 55–64 61 7.2 (5.1–9.3) Total 835 100 (NA) Province Nairobi 101 9.9 (5.5–14.3) Central 43 4.9 (2.9–6.9) Coast 19 1.4 (0.5–2.3) Eastern 48 5.3 (2.8–7.9) North-Eastern 8 0.4 (0.0–0.7) Nyanza 405 49.3 (42.4–56.3) Rift Valley 100 18.4 (13.1–23.8) Western 111 10.3 (5.8–14.9) Total 835 100 (NA) Area of residence Rural 640 80.2 (74.6–85.8) Urban 195 19.8 (14.2–25.4) Total 835 100 (NA) Educational level No primary 40 6.3 (3.3–9.2) Incomplete primary 341 42.5 (37.7–47.2) Complete primary 191 22.5 (19.2–25.7) Secondary or higher 263 28.8 (24.4–33.1) Total 835 100 (NA) Marital status Never married or cohabited 421 52.5 (48.6–56.5) Currently married or cohabiting 382 44.1 (40.4–47.7) Separated or divorced 22 2.2 (1.1–3.3) Widowed 10 1.2 (0.2–2.2) Total 835 100 (NA) Ethnic tribe Embu 2 0.3 (0.0–0.6) Kalenjin 36 6.7 (2.2–11.2) Kamba 6 1.1 (0.0–2.3) Kikuyu 47 5.8 (3.2–8.3) Kisii 4 0.4 (0.0–1.0) Luhya 62 5.5 (2.1–8.9) Luo 540 63.1 (56.5–69.6) Masai 3 0.5 (0.0–1.1) Meru 29 3.6 (1.6–5.6) Mijikenda 0 0 (NA) Somali 5 0.3 (0.0–0.6) Taita/Taveta 2 0.1 (0.0–0.2) Swahili 0 0 (NA) Other 99 12.8 (7.9–17.7) Total 835 100 (NA) Self-reported HIV statusb Never tested or unknownc 627 77.8 (73.9–81.8) Negative 185 22.1 (18.1–26.1) (continues. . .) Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412648 Research Male circumcision in Kenya Zebedee Mwandi et al. 14.7% reported that they had consis- tently used a condom with their last partner and 78.2% reported they had at least one sexual partner of unknown or discordant HIV status in the 12 months before the survey. In addition, 65.3% reported unprotected sex with a partner of unknown or discordant HIV status during the three most recent sex acts in the last 12 months (Table 3). Discussion We found that the prevalence of HIV infection was three times lower in uncir- cumcised men than in circumcised men, which provides evidence for a strong association between circumcision and HIV infection and confirms the need for interventions to expand male circum- cision in Kenya. Overall, 15% of men aged 15 to 64 years in Kenya were not circumcised in 2007 and an estimated 90% of these men lived in the Nyanza, Rift Valley, Nairobi or Western Province, which are the main target regions of the national strategy for male circumcision. Uncircumcised, HIV-uninfected men were typically young and lived in a rural area. The majority were educated to at least primary school level, were not married or cohabiting, belonged to the Luo ethnic tribe and had never been tested for HIV. Almost 80% re- ported having had sex with a partner of unknown or discordant HIV status in the last 12 months and few used con- doms during these high-risk sex acts. However, there was a low level of sexual activity among HIV-uninfected men under 20 years of age, suggesting that, to reduce HIV transmission among newly sexually-active individuals, this age group should be targeted by the national programme for male circumcision and HIV testing, preferably before or soon after the men’s sexual debut. We found that circumcision was mainly performed during adolescence and at home, with a high proportion be- ing performed by traditional providers. However, traditional circumcision in a nonmedical setting has been associated with a high rate of adverse events, such as bleeding or infection.15,16 The national strategy for male circumcision includes plans to increase the use of safer surgical practices by trained health-care workers. This will involve engaging traditional male circumcision providers and edu- cating communities and parents on the safety benefits for preadolescent boys. We found that the prevalence of HSV-2 infection was significantly higher in uncircumcised than circumcised men. Although it has been shown that male circumcision has a protective effect against HSV-2 and human papillomavi- rus infections,3 approximately one third of uncircumcised, HIV-uninfected men in Kenya in 2007 were already infected with HSV 2. Given that the risk of infec- tion increases with age, performing male circumcision before young men become sexually active could help reduce the risk of acquiring both HSV-2 and HIV infections. Finally, since the majority of uncircumcised men were from the Luo ethnic group, continuous engage- ment with elders and leaders of the Luo community could facilitate cultural ac- ceptance of male circumcision. Our study had limitations. First, cross-sectional surveys cannot estab- lish a direct relationship between cause and effect. Second, physical examina- tions were not performed to determine whether there was any bias in the reporting of male circumcision. Third, we recorded information on whether circumcision was performed at home or in a health-care facility but not on whether it was performed as part of a community ritual, which is common practice in traditionally circumcising communities. Fourth, since sexual be- haviour was self-reported, participants may have been reluctant to disclose some sexual risk factors. Fifth, some subgroup comparisons were limited by small sample sizes. Finally, due to cultural sensitivity concerning ethnic- Variable Uncircumcised, HIV-uninfected men (n = 835) No. Weighted %a (95% CI) Positive 1 0.1 (0.0–0.3) Total 813 100 (NA) HSV-2 infection No 526 66.8 (63.4–70.3) Yes 275 33.2 (29.7–36.6) Total 801 100 (NA) Consistent condom use with most recent partner in the last 12 months Yes 83 14.7 (11.2–18.1) No 465 85.3 (81.9–88.8) Total 548 100 (NA) No. of sexual partners of unknown or discordant HIV status in last 12 months 0 120 21.8 (16.2–27.5) 1 340 62.9 (56.5–69.3) 2 65 11.6 (8.5–14.6) 3+ 23 3.7 (2.0–5.3) Total 548 100 (NA) Had unprotected sex in the last 12 monthsd With partner of unknown or discordant HIV status 345 65.3 (58.8–71.8) With partner of concordant HIV status 108 19.8 (15.2–24.5) Did not have unprotected sex 80 14.9 (11.3–18.4) Total 533 100 (NA) CI, confidence interval; HIV, human immunodeficiency virus; HSV-2, herpes simplex virus 2; NA, not applicable. a Each man’s response was weighted to take its sampling probability into account and to adjust for the nonresponse rate. b Only 813 of the 835 uncircumcised, HIV-uninfected men responded to the question regarding known HIV status. c HIV status was unknown for 16 men. d An individual was classified as having had unprotected sex in the last 12 months if he had sex without protection during at least one of the three most recent sex acts in the last 12 months. (. . .continued) 649Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412 Research Male circumcision in KenyaZebedee Mwandi et al. صخلم 2007 ماعل اينيك في زديلإا شرؤم حسم نم ةدافتسلما سوردلا :اينيك في روكذلا ناتخ جمارب للاخ نم اينيك في روكذلا ناتخ جمابرل تاداشرلإا ميدقت ضرغلا قيقحتلاو ناتخلل اوعضيخ لم نيذلا لاجرلا نم ناكسلا ددع ريدقت يشربلا يعانلما زوعلا سويرفب ىودعلاو ناتلخا ينب طابترلاا في لم نيذلا لاجرلا لىإ صوصلخا هجو لىع ةراشلإاب ،)HIV( .يشربلا يعانلما زوعلا سويرفب ينباصلما يرغ ناتخلل اوعضيخ حواترت نيذلا لاجرلاب ةقلعتلما تانايبلا صلاختسا مت ةقيرطلا ماعل اينيك في زديلإا شرؤم حسم نم ةنس 64 لىإ 15 ينب مهرماعأ اهرابتخلا مدلا تانيع عجمو تلاباقم لىع لمتشا يذلاو ،2007 سويرفو يشربلا يعانلما زوعلا سويرفب ةباصلإا فاشتكا ةيغب ىودعلا راشتنا باسح متو .)HSV-2( 2 طمنلا طيسبلا سبرلها متو ةينيكلا تاعطاقلما في ناتلخاو يشربلا يعانلما زوعلا سويرفب يننوتخلما لاجرلل سينلجا كولسلاو ةيفارغميدلا صئاصلخا ليجست يشربلا يعانلما زوعلا سويرف ىودعب ينباصلماو يننوتخلما يرغو .يشربلا يعانلما زوعلا سويرف ىودعب ينباصلما يرغو يشربلا يعانلما زوعلا سويرفب ىودعلا راشتنا ةبسن تغلب جئاتنلا لصاف( % 13.2 يننوتخلما يرغ لاجرلا ىدل ينطولا ديعصلا لىع % 3.9 ةبسنب ةنراقم )15.7 لىإ 10.8 :ةقثلا لصاف ،% 95 ةقثلا تمضو .يننوتخلما لاجرلا ينب )4.5 لىإ 3.3 :% 95 ةقثلا لصاف( ىودعب ينباصلما يرغ يننوتخلما يرغ لاجرلل ددع لىعأ ازناين ةعطاقم ةعطاقم اهتلت ،)صخش 601709( يشربلا يعانلما زوعلا سويرف مهمظعم ناكو ،لياوتلا لىع ةيبرغلا ةعطاقلماو بيويرنو لياف تفير لاجرلا ءلاؤه نم % 77.8 فرعي لمو .ةيقرعلا وول ةليبق لىإ يمتني % 33.2 ةبسن تناكو ،ميهدل يشربلا يعانلما زوعلا سويرف ةلاح ،كلذ لىع ةولاعو .2 طمنلا طيسبلا سبرلها سويرفل ةيبايجإ مهنم ينثلاا للاخ ةيممح يرغ ةيسنج تاسرامم في % 65.3 ةبسن تطروت يشربلا يعانلما زوعلا سويرف ةلاح كيشر عم ةيضالما ًارهش شرع % 14.7 ىوس مدختسي لمو ةفورعم يرغ وأ ةقفاوتم يرغ هيدل ىوس نكت لم هنأ ديب .كيشر ثدحأ عم ماظتناب يركذلا لزاعلا ىودعب ينباصلما يرغو ،يننوتخلما يرغ لاجرلا نم % 21.8 ةبسن 19 لىإ 15 ينب مهرماعأ حواترت نمم ،يشربلا يعانلما زوعلا سويرف .ًايسنج ءاطشن ةنس لىع اينيك في روكذلا ناتخ ةيجيتاترسا زكرت نأ ينعتي جاتنتسلاا يرغو يننوتخلما يرغ لاجرلا نم ددع لىعأ مضت يتلا تاعطاقلما فدهتست نأو يشربلا يعانلما زوعلا سويرف ىودعب ينباصلما .ةيرصق ةترفب هدعب وأ سينلجا طاشنلا لبق بابشلا ity and provinces in Kenya, we did not amalgamate ethnic tribes and provinces with small sample sizes. As a result, uncertainty in estimates derived using these samples may be large and the fig- ures should be interpreted with caution. The 2009 national male circumci- sion strategy stipulates that 80% of men in Kenya should be circumcised by 2014.9,17 In Nyanza province, implemen- tation began in October 2008 and, by the end of September 2011, approximately 210 000 men had been circumcised, which is 50% of the target for 2014 (Athanasius Ochieng, personal com- munication). The use of outreach and mobile units involving dedicated teams has been recommended as the best ap- proach for reaching men aged between 15 and 49 years in the first phase of the national strategy.18 However, efforts will be required to increase the acceptability of male circumcision since only 65% (range: 29–87) of uncircumcised men in sub-Saharan Africa find the procedure aceptable.19 In summary, our findings confirm that male circumcision programmes in Kenya should focus on four specific provinces, that circumcision by medical providers in traditionally circumcising regions should be increased and that comprehensive messages about the prevention of HIV transmission should be provided at the time of circumci- sion. In addition, our results suggest that circumcision programmes should specifically target younger men before or shortly after their sexual debut when they may still be free of HIV and HSV- 2 infections. National survey data on sexual behaviour and the prevalence of HIV infection can be useful for resource allocation and for planning male circumcision programmes in sub- Saharan Africa in addition to providing essential data for HIV prevention. The 2007 Kenya AIDS Indicator Survey provided baseline data for the national male circumcision strategy for 2009 to 2014. It is anticipated that the 2012 Ke- nya AIDS Indicator Survey will inform the development of the new strategy for 2014 to 2019. ■ Acknowledgements We thank Eddas Bennett, US Centers for Disease Control and Prevention; Willi McFarland, University of California San Francisco; and Michael Arnold, Godfrey Baltazar, Isack Baya, John Bore, Sufia Dadabhai, Helen Dale, Tura Galgalo, Catherine Gichimu, Allen Hightower, Jared Ichwara, George Kichamu, An- drea Kim, Evelyn Kim, Samuel Kipruto, George K’opiyo, Ernest Makokha, Barba- ra Marston, Lawrence Marum, Margaret Mburu, Jonathan Mermin, Joy Mirjah- angir, Rex Mpazanje, Ibrahim Mohamed, Patrick Muriithi, James Muttunga, Carol Ngare, Raymond Nyoka, Linus Odawo, Samuel Ogola, Christopher Omolo, Ray Shiraishi, John Wanyungu and Anthony Waruru, 2007 Kenya AIDS Indicator Survey study group. Funding: This study was funded by the US President’s Emergency Plan for AIDS Relief through the US Centers for Disease Control and Prevention, US Department of Health and Human Services. Competing interests: None declared. Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412650 Research Male circumcision in Kenya Zebedee Mwandi et al. 摘要 肯尼亚男性包皮环切计划：肯尼亚2007 年艾滋病指标调查的经验教训 目的 通过肯尼亚未进行包皮环切男性人群数据估测，以 及特别以未进行包皮环切、未感染HIV男性人群为参照进 行的包皮环切与艾滋病毒（HIV）感染相关性研究，为肯 尼亚男性包皮环切计划提供指导。 方法 采用的15 岁至64 岁男性的数据来源于2007 年肯尼 亚艾滋病指标调查，其中涉及访视和采血进行艾滋病毒和 单纯疱疹病毒2 型（HSV-2）检测。计算肯尼亚各省艾滋 病毒感染率和包皮环切普及率，记录进行包皮环切和未进 行包皮环切、受艾滋病毒感染和未受艾滋病毒感染的男性 人口特征和性行为。 结果 包皮环切的男性的HIV感染率为3.9%（95% 置信区 间：3.3-4.5），未进行包皮环切的男性HIV感染率为13.2% （95% 置信区间：10.8-15.7）。尼安萨省未进行包皮环 切、未感染HIV的男性估计人数最多（即601709），其 次分别是东非大裂谷、内罗毕和西部省，大部分属于卢奥 民族部落。这些男性中，77.8%的男性不知道自己的HIV 感染状况，33.2%男性的HSV-2 为阳性。此外，65.3%男 性在过去12 个月中与艾滋病毒单阳或未知的的性伙伴有 过不安全的性行为，只有14.7%的男性在最近期与性伙伴 的性行为中始终使用避孕套。然而，在未进行包皮环切、 未感染艾滋病毒的15 至19 岁的男子中，只有21.8%男性 处于性活跃状态。 结论 肯尼亚男性包皮环切战略应将重点放在未进行包皮 环切、未感染HIV人数最高的各省，并以初次性行为之前 或之后不久的年轻男性为目标。 Résumé Programmes de circoncision masculine au Kenya: leçons tirées de l’enquête de 2007 sur les indicateurs du SIDA au Kenya Objectif Conseiller des programmes de circoncision masculine au Kenya en estimant le nombre d’hommes non circoncis et en recherchant l’association entre la circoncision et l’infection par le virus de l’immunodéficience humaine (VIH), avec une référence particulière aux hommes non circoncis et non infectés par le VIH. Méthodes Des données sur des hommes âgés de 15 à 64 ans ont été obtenues de l’enquête de 2007 sur les indicateurs du SIDA au Kenya, impliquant des entretiens et des prises de sang afin de rechercher la présence du VIH et du virus de l’herpès simplex 2 (VHS-2). La prévalence de l’infection par le VIH et la circoncision dans les provinces kenyanes a été calculée, et les caractéristiques démographiques ainsi que le comportement sexuel des hommes circoncis et non circoncis, des hommes infectés et non infectés par le VIH ont été enregistrés. Résultats La prévalence nationale de l’infection par le VIH chez les hommes non circoncis s’élevait à 13,2% (intervalle de confiance de 95%, IC: 10,8–15,7) par rapport à un pourcentage de 3,9% (IC de 95%: 3,3–4,5) chez les hommes circoncis. La province de Nyanza présentait l’estimation du plus grand nombre d’homme non circoncis et d’hommes non infectés par le VIH (601 709), suivie de la vallée du Rift, de Nairobi et de la province occidentale, respectivement, dont la plus grande partie appartenait à la tribu ethnique des Luo. Chez ces hommes, 77,8% ne connaissaient pas leur séropositivité et 33,2% étaient positifs au VHS-2. De plus, 65.3% d’entre eux avaient eu des rapports sexuels non protégés avec une partenaire de statut HIV inconnu ou discordant au cours des 12 derniers mois, et seuls 14,7% d’entre eux utilisaient constamment des préservatifs avec leur dernière partenaire. Cependant, seuls 21,8% des hommes non circoncis et non infectés par le VIH âgés de 15 à 19 ans étaient sexuellement actifs. Conclusion La stratégie de circoncision des hommes kenyans doit s’orienter sur les provinces présentant le plus grand nombre d’hommes non circoncis et non infectés par le VIH, mais aussi cibler les jeunes hommes avant ou peut de temps après leur première expérience sexuelle. Резюме Программы по обрезанию крайней плоти у мужчин в Кении: уроки, извлеченные из Индикаторного исследования СПИДа в Кении, 2007 г. Цель Обеспечить руководство программами по обрезанию крайней плоти у мужчин в Кении посредством оценки численности мужчин, не подвергшихся обрезанию, и исследование связи между обрезанием крайней плоти и инфицированием вирусом иммунодефицита человека (ВИЧ) с особым акцентом на ВИЧ- неинфицированных мужчинах, не подвергшихся обрезанию. Методы Данные по мужчинам возрастной группы от 15 до 64 лет были получены из Индикаторного исследования СПИДа в Кении, 2007 г., которое включало опросы и взятие крови для проведения теста на наличие ВИЧ и вируса простого герпеса 2 (ВПГ-2). Были собраны данные по распространенности ВИЧ-инфекции и обрезанию крайней плоти в провинциях Кении, а также регистрировались демографические показатели и сексуальное поведение мужчин, подвергшихся и не подвергшихся обрезанию крайней плоти, ВИЧ-инфицированных и ВИЧ-неинфицированных мужчин. Результаты Национальная распространенность ВИЧ-инфекции у мужчин, не подвергшихся обрезанию, составила 13,2% (95% доверительный интервал, ДИ: 10,8–15,7) в сравнении с 3,9% (95% ДИ: 3,3–4,5) среди мужчин, подвергшихся обрезанию. В провинции Ньянза зарегистрировано наибольшее число мужчин, подвергшихся обрезанию крайней плоти, ВИЧ-инфицированных мужчин (т. е. 601 709), за которой следуют долина Рифт, Найроби и Западная провинция, соответственно. Большинство мужчин из данного числа принадлежат этническому племени Луо. Из этого числа мужчин, 77,8% не знали о своем ВИЧ-статусе и 33,2% имели ВПГ-2 антитела положительных образцов. Кроме того, 65,3% вступали в незащищенный половой контакт с партнером с дискордантным или неизвестным ВИЧ статусом за последние 12 месяцев и только 14,7% постоянно использовали презервативы при половом контакте с последним партнером. Тем не менее, только 21,8% ВИЧ-неинфицированных мужчин, Bull World Health Organ 2012;90:642–651 | doi:10.2471/BLT.11.096412 651 Research Male circumcision in KenyaZebedee Mwandi et al. не подвергшихся обрезанию, в возрастном диапазоне от 15 до 19 лет вели активную половую жизнь. Вывод Кенийская стратегия по обрезанию крайней плоти у мужчин должна быть сконцентрирована на провинциях с высоким числом ВИЧ-неинфицированных мужчин, не подвергшихся обрезанию, и направлена на юношей до или вскоре после начала половой жизни. Resumen Los programas de circuncisión masculina en Kenia: lecciones de la Encuesta de indicadores del SIDA en Kenia 2007 Objetivo Proporcionar orientación para los programas de circuncisión masculina en Kenia calculando la población de hombres circuncidados e investigando la relación entre la circuncisión y la infección con el virus de la inmunodeficiencia humana (VIH), haciendo alusión especial a los hombres no circuncidados ni infectados por el VIH. Métodos Los datos acerca de los hombres con edades comprendidas entre 15 y 64 años se obtuvieron de la Encuesta de indicadores del SIDA en Kenya del año 2007, que incluyó entrevistas y la recogida de muestras de sangre para realizar las pruebas del VIH y del virus del herpes simple de tipo 2 (VHS-2). Se calculó la prevalencia de la infección por el VIH y la circuncisión en las provincias de Kenia y se registraron las características demográficas y el comportamiento sexual de los hombres circuncidados y no circuncidados, infectados y no infectados con el VIH. Resultados La prevalencia nacional de la infección por VIH en los hombres circuncidados fue del 13,2% (intervalo de confianza del 95%, IC: 10,8 – 15,7) comparada con el 3,9% (IC 95%: 3,3 – 4,5) entre los hombres circuncidados. La provincia de Nyanza tuvo el mayor número estimado de hombres no circuncidados y no infectados por el VIH (esto es, 601 709), seguida por la provincia Rift Valley, Nairobi y la provincia Occidental, respectivamente, y la mayoría de ellos pertenecía a la tribu étnica Luo. De esos hombres, el 77,8% no conocía su estado serológico y el 33,2% estaba infectado con el VHS-2. Además, el 65,3% había mantenido relaciones sexuales sin protección con una pareja serodiscordante o que no conocía su estado serológico en los últimos 12 meses y sólo el 14,7% había empleado preservativos de manera sistemática con su pareja más reciente. No obstante, sólo el 21,8% de los hombres circuncidados e infectados por el VIH con edades entre los 15 y los 19 años era sexualmente activo. Conclusión La estrategia de circuncisión masculina en Kenya debería centrarse en las provincias con el mayor número de hombres no circuncidados y no infectados por el VIH y dirigirse a los hombres jóvenes antes o poco después de la primera relación sexual. References 1. AIDS epidemic update 2009. Geneva: World Health Organization & Joint United Nations Programme on HIV/AIDS; 2009. 2. Weiss HA, Quigley MA, Hayes RJ. Male circumcision and risk of HIV infection in sub-Saharan Africa: a systematic review and meta-analysis. AIDS 2000;14:2361–70. PMID:11089625 3. Tobian AA, Serwadda D, Quinn TC, Kigozi G, Gravitt PE, Laeyendecker O et al. Male circumcision for the prevention of HSV-2 and HPV infections and syphilis. N Engl J Med 2009;360:1298–309. PMID:19321868 4. Auvert B, Taljaard D, Lagarde E, Sobngwi-Tambekou J, Sitta R, Puren A. Randomized, controlled intervention trial of male circumcision for reduction of HIV infection risk: the ANRS 1265 Trial. PLoS Med 2005;2:e298. PMID:16231970 5. Bailey RC, Moses S, Parker CB, Agot K, Maclean I, Krieger JN et al. Male circumcision for HIV prevention in young men in Kisumu, Kenya: a randomised controlled trial. Lancet 2007;369:643–56. PMID:17321310 6. Gray RH, Kigozi G, Serwadda D, Makumbi F, Watya S, Nalugoda F et al. Male circumcision for HIV prevention in men in Rakai, Uganda: a randomised trial. Lancet 2007;369:657–66. PMID:17321311 7. New data on male circumcision and HIV prevention: policy and programme implications. WHO/UNAIDS Technical Consultation. Geneva: World Health Organization & Joint United Nations Programme on HIV/AIDS; 2007. 8. Central Bureau of Statistics. Kenya Demographic and Health Survey. Calverton: ORC Macro; 2003. 9. Kenya national strategy for voluntary medical male circumcision. Nairobi: Kenya Ministry of Public Health and Sanitation; 2009. 10. Bollinger L, DeCormier Plosky W, Stover J. Male circumcision: decision makers’ program planning tool, calculating the costs and impacts of a male circumcision program. Washington: Futures Group; 2009. 11. Weiss HA, Hankins CA, Dickson K. Male circumcision and risk of HIV infection in women: a systematic review and meta-analysis. Lancet Infect Dis 2009;9:669–77. PMID:19850225 12. National AIDS and STI Control Programme. 2007 Kenya AIDS Indicator Survey: final report. Nairobi: Ministry of Health; 2009. 13. Oluoch T, Mohammed I, Bunnell R, Kaiser R, Kim AA, Gichangi A et al. Risk factors for HIV infection in Kenya: a national population-based survey. Open AIDS J 2011;5:125–34. PMID:22253668 14. The 1999 population and household census. Nairobi: Kenya National Bureau of Statistics; 1999. 15. Eaton L, Kalichman SC. Behavioral aspects of male circumcision for the prevention of HIV infection. Curr HIV/AIDS Rep 2009;6:187–93. PMID:19849961 16. Bailey RC, Egesah O, Rosenberg S. Male circumcision for HIV prevention: a prospective study of complications in clinical and traditional settings in Bungoma, Kenya. Bull World Health Organ 2008;86:669–77. PMID:18797642 17. Mwandi Z, Murphy A, Reed J, Chesang K, Njeuhmeli E, Agot K et al. Voluntary medical male circumcision: translating research into the rapid expansion of services in Kenya, 2008–2011. PLoS Med 2011;8:e1001130. PMID:22140365 18. Considerations for implementing models for optimizing the volume and efficiency of male circumcision services. Field testing ed. Geneva: World Health Organization; 2010. 19. Westercamp N, Bailey RC. Acceptability of male circumcision for prevention of HIV/AIDS in sub-Saharan Africa: a review. AIDS Behav 2007;11:341–55. PMID:17053855