Preventing mother·to·child transmission of HIV

28 World Health • 51 si Year, No. 6, November-December 1998 Preventing mother·lo·child transmission of HIV Vallop Thaineua & Marc Lallemant Thailand has made great strides in the area of perinatal HIV prevention, and this experience offers important lessons for both industrialized and developing countries. Infants born to H/V-infected mothers who do not breastfeed are in less danger of an AIDS-related death, because mother-to-child transmission of HIV is now to a large extent preventable. During the past three decades, much progress has been made in the field of mother and child health. In almost every country, maternal and infant mortality rates have decreased dramatically as a result of such public health initia- tives as improved prenatal and delivery care and child immuniza- tion programmes. Now the HIV epidemic threatens to undo much of this progress. According to WHO and UN AIDS, about 1000 infants are infected with HIV each day. Most of them acquire the virus from their mother, who often only discov- ers her own HIV status when she finds she has given birth to an in- fected child. However, these infants are now in less danger of an AIDS- related death, because mother-to- child transmission of HIV is now to a large extent preventable. In Thailand, AIDS has already reversed much of the progress made in reducing child mortality and Thailand's Deputy Minister of Public Health congratulates on HIV-positive mother whose second baby has ;ust been delivered by coesoreon section. She has completed a short-treatment course of zidovudine to prevent HIV transmission to her baby Photo WHO/Ministry of Public Health of Thailand morbidity. In the early 1990s, espe- cially in northern Thailand, paedi- atric wards began to fill with children with AIDS; as they died, many more took their place. At the same time, many other children became orphans through losing their mothers to AIDS. By 1995, 800 000 persons had already become infected with HIV, while the prevalence in pregnant women varied from 1% to 8%, depending on the region. In response to this crisis, the government started a multisector AIDS programme based on the following imperatives: 1) the public should be informed; 2) the basic human rights of HIV-infected per- sons should be protected; 3) re- search appropriate to the Thai situation should be carried out; and 4) a substantial budget should be allocated for prevention and care. Most importantly, this comprehen- sive programme involved from the beginning all government ministries, nongovemmental organizations, donors and private businesses. A few years after the start of this collaborative effort, Thailand saw a sharp decrease in the incidence of HIV infection. Among young mili- tary conscripts, for example, it dropped from 12.4% in 1993 to 3.6% in 1997. Within this programme, Thailand has tackled the specific problem of mother-to-child transmission of HIV. For instance, while Thailand fully supports the UNICEF "baby- friendly" initiative and continues to promote breastfeeding, the Ministry of Public Health decided to recom- mend formula feeding to HIV- infected women. It has been demonstrated that mother-to-child transmission of HIV occurs not only during pregnancy and at delivery, but also after the birth, through breastfeeding. This late transmis- sion accounts for as many as one- third of the cases of child infection. World Health • 51st Yeor, No. 6, November-December 1998 To reduce it, efforts are made to provide formula milk free of charge to women who cannot afford it, and to follow up their children through the regular postnatal care system. ZDV drug treatment In 1994, research showed that three months' treatment with the drug zidovudine (ZDV) for the mother at the end of pregnancy, with an intra- venous loading dose during labour and a six-week treatment for the infant, while not breastfeeding, will reduce mother-to-child transmission by two-thirds. Thailand had already developed the medical expertise and health care infrastructure to benefit from these findings. In mid-1995, the World Bank and WHO helped the Ministry of Public Health to analyse the economics of antiretroviral therapy. They con- cluded that, given the Ministry 's antiretroviral budget and the quality of Thailand's health care infrastruc- ture, preventive use ofZDV for pregnant women was not only af- fordable but much more cost- effective than alternative uses of the drug such as treating people with HIV illnesses. Subsequently, the Thai Food and Drug Administration approved the use of ZDV for the prevention of paediatric AIDS. While some pregnant women re- ceived ZDV on an individual basis or through private organizations such as the Thai Red Cross, public health authorities in the north, the region most affected by the HIV epidemic, decided to launch a com- prehensive programme to provide ZDV to all HIV-infected women in the area. Knowing that most mother-to- child transmission occurs at the time of delivery, the public health author- ities in the north were convinced that a treatment regimen similar to, but shorter and simpler than, the one used in North America and Europe would significantly decrease the number of paediatric AIDS cases, cost less and be more accessible. Thus, they quickly established a comprehensive programme of coun- selling, HIV testing, ZDV prophy- laxis and formula feeding for HIV- infected pregnant women in the six northern provinces, without waiting for the results of ongoing clinical trials designed to assess the efficacy of shortened ZDV regimens. Within six months, most of the district hospitals in that region had joined the programme, and in those hospitals more than 60% of HIV- positive pregnant women had been treated. This result was achieved with limited external support at an additional cost of $0.13 per capita per year, a cost affordable even in the context of an economic crisis, since it represents less than 1% of the country's public health expendi- tures. Thailand has made great strides in the area of perinatal HIV preven- tion, and this experience offers some important lessons for both developed and industrialized countries. Firstly, there is no need to wait to save the lives of infants born to HIV-positive mothers who have alternatives to breastfeeding: efforts can and must be made now to transform proven clinical research into public health interventions as quickly as possible. As Thailand has shown, local collab- orative programmes can have a significant impact. Secondly, a country's current system of coun- selling, HIV testing, prenatal care 29 and follow-up care for mother and infant may never quite be ready for the ideal introduction of a new intervention, so it is necessary to determine the goal of the interven- tion first and then begin to reorga- nize the health care system to meet the patients' needs. Thirdly, the involvement of local health care personnel will facilitate and acceler- ate the changes necessary to ensure the success of the intervention. Just as Thailand was able to benefit from the research and experiences of other countries, today other countries can hope to benefit substantially from Thailand's experiences. • Or Va/lop Thaineua is Genera/Inspector of Health for Region I 0, covering the northernmost provinces of Thailand. Or Marc Lallemant is Director of the North Thailand Perinatal HIV Prevention Trial, a collaborative effort between Thailand, France and the United States. Their address is 57/2 Fa ham Rood, Soi 3 (Wot Langko} Muong, Chiang Mai 50000, Thailand. While continuing to promote breastfeeding in general, Thailand advocates the use of formula milk for infants whose mothers are HIV·positive. This has resulted in on important decrease in mother-to- child transmission of the virus. Photo Format/Impact Visuals/L. Me/nick