-- Experts have concluded the safety and effectiveness of antiretroviral (ARV) regimens which prevent HIV transmission from mother to child warrant their use beyond pilot projects and research settings.
According to a technical consultation held in Geneva from 11-13 October 2000, the prevention of mother-to-child transmission of HIV -- the virus that causes AIDS - should be included in the minimum standard package of care for HIV-positive women and their children. The meeting also recommended that "there is no justification to restrict use of any of these regimens to pilot project or research settings."
"We welcome these new recommendations, particularly those relating to the use of nevirapine", said Dr Awa-Marie Coll-Seck, UNAIDS Director of Policy, Strategy and Research. "It is my sincere hope that more women will now have access to mother-to-child prevention programmes in developing countries".
"A number of available regimens are known to be effective and safe," said Dr Winnie Mpanju-Shumbusho, Director of the HIV/AIDS/STI Initiative of WHO. "The choice should be determined according to local circumstances on the grounds of costs and practicality, particularly as related to the availability and quality of antenatal care."
The safety of preventive treatments including zidovudine
alone, zidovudine and lamivudine
, and nevirapine, has been studied extensively for both breastfeeding and non-breastfeeding populations worldwide. Information currently available does not suggest any adverse effects on the health of the mother, growth and development of infants, or the health and mortality of infants infected despite prophylaxis.
The most complex regimen includes antepartum and intrapartum zidovudine for the mother and post-natal doses for the infant. The simplest regimen requires a single dose of nevirapine at the onset of labour and a single dose for the newborn. These regimens work by decreasing viral load in the mother and through prophylaxis of the infant during and after exposure to virus.
Previous recommendations from March 2000 had stated that because of possible concerns about the rapid development of nevirapine-resistant virus in women using this intervention, nevirapine should be used within the context of pilot and research projects only.
While resistant virus may develop quickly to antiretroviral drug regimens that do not fully suppress viral replication, such as those including lamivudine and nevirapine, evidence indicates that virus containing drug resistant mutations decreases once the antiretroviral drugs are discontinued. Mutant virus may remain present in an individual in very low levels, which could reduce the effectiveness of future antiretroviral treatment for the mother. However, the meeting concluded that the benefit of decreasing mother-to-child HIV transmission with these antiretroviral drug prophylaxis regimens greatly outweighs any theoretical concerns related to development of drug resistance.
The prevention of mother-to-child transmission involves more than simple provision of antiretroviral drugs. It also requires appropriate counselling and testing services, as well as support for mothers and infants, including counselling on infant feeding options.
There is continued concern that up to 20% of infants born to HIV-positive mothers may acquire HIV through breastfeeding. The meeting concluded that the guidelines issued in 1998 remain valid. An HIV-infected women should receive counselling, which includes information about the risks and benefits of different infant feeding options, and specific guidance in selecting the option most likely to be suitable for her situation. The final decision should be the woman's, and she should be supported in her choice. For HIV-positive women who choose to breastfeed, exclusive breastfeeding is recommended for the first months of life, and should be discontinued when an alternative form of feeding becomes feasible.
Each year, more than 600 000 infants become infected by HIV/AIDS, mainly in developing countries. Since the beginning of the HIV epidemic, an estimated 5.1 million children worldwide have been infected with HIV. Mother-to-child transmission is responsible for more than 90% of these infections. Two-thirds are believed to occur during pregnancy and delivery, and about one-third through breastfeeding. As the number of women of childbearing age infected by HIV rises, so does the number of infected children.
The WHO Technical Consultation was held on behalf of the UNAIDS/UNICEF/UNFPA/WHO InterAgency Task Team on the Prevention of Mother-to-Child Transmission of HIV. Participants included scientists, managers of national AIDS control programmes, HIV-positive mothers, non-governmental organizations, and United Nations agencies. Participants came from Africa, Asia, Europe, the Caribbean and the Americas.