Simplified antiviral prophylaxis with or and without artificial feeding to reduce mother-to-child transmission of HIV in low and middle income countries: modelling positive and negative impact on child survival.

BACKGROUND Antiviral prophylaxis is recommended for HIV positive mothers to prevent mother-to-child transmission of HIV. To date UNAIDS and WHO policy has been based on a study in Thailand which showed a reduction in transmission by half with short course AZT (Zidovudine) treatment together with artificial feeding. We modelled the possible positive and negative effects on child deaths in low and middle resource developing country settings of two interventions to reduce mother to child transmission (MTCT) of HIV: antenatal testing, short-course antivirals (zidovudine or nevirapine), firstly with and then without artificial feeding. MATERIAL AND METHODS Estimates are made of child lives likely to be saved by the programme by age ten years, balanced against increases in deaths due to more uninfected mothers choosing to use artificial feeds where these are part of the intervention. Mid-point values for variables affecting the balance of mortality gains and losses are taken from recent published data for low and middle income developing countries and a sensitivity analysis is undertaken. RESULTS In low income settings the use of antivirals alone would result in an estimated gain in child survival of around 0.36%, representing 360 deaths avoided from a birth cohort of 100,000 by age 10 years. Adding artificial feeding could reduce the gain to 0.03% (30 deaths avoided). In middle income settings the gain from antivirals alone would be 0.26% but as 'spill-over' of artificial feeding to uninfected women was more likely it could result in a net increase of child deaths of up to 1.08% (1,080 additional deaths). A sensitivity analysis emphasised this potential for regimens using artificial feeding if progamme participation was low, and under most circumstances in middle income settings. CONCLUSIONS HIV testing and use of antivirals by infected mothers, if well implemented, will be effective at a population level in reducing MTCT. However the addition of artificial feeding is potentially be a high risk strategy, especially in middle income countries.