PEPFAR: Early weaning to avoid mother-to-child transmission of HIV could endanger infant’s health

Early weaning to prevent mother-to-child transmission (PMTCT) of HIV can pose considerable challenges in resource-limited settings — and could put HIV-exposed infant’s health in serious jeopardy —according to reports presented at the 2006 PEPFAR Implementers meeting in Durban this June.

Infant feeding background

Breastfeeding is usually the best way to feed an infant. Aside from being a good source for nutrition, mother’s milk contains antibodies and other factors that may protect infants from community acquired infections. However, when a woman is HIV-infected, breastfeeding also carries of risk of HIV transmission. Therefore, UNICEF and World Health Organization (WHO) guidelines recommend that, in resource-limited settings, women with HIV exclusively breastfeed their infants for at least several months but to wean them as soon as possible once a consistent, safe and suitable alternative feeding option is available.

However, in many resource-limited settings, this guidance poses logistical problems in providing good nutrition, and may even endanger the child’s life.

For example, researchers from Elizabeth Glaser Pediatric AIDS Foundation (EGPAF) and Health Alliance International reported the results of a study demonstrating that in parts of Mozambique, most mothers are unable to provide sufficient nutrition following early cessation of breastfeeding.

Chronic malnutrition in children under five is common in parts of Mozambique, with rates ranging from 34 to 42%. In this study, 67 HIV-positive mothers and 70 mothers of unknown status were recruited from three different provinces and then interviewed to gather information on household food security and their infants' diet between the six to twelve month period. Replacement diets were then assessed using WHO linear programming methods which determine whether the combinations of locally available foods could meet the nutritional needs of non-breastfed infants.

The majority (78%) of HIV-positive mothers with infants over six months of age had stopped breastfeeding compared to all but 10% of the women of unknown status who were still breastfeeding their infants.

Only 10% of the mothers reported that the replacement diet in children regularly included iron-rich and animal-sourced foods that non-breastfeeding infants require. In one province (where there was a food shortage for almost have the mothers during the study), linear programming results indicated that the local replacement diet couldn’t possibly meeting the infants nutritional needs, while in the other two provinces, replacement diets could be adequate but only when it contained a range of nutrient rich foods in addition to the common staple diet. However, including these foods effectively doubled the cost of feeding the infant.

The researchers concluded that “early breastfeeding cessation is likely to increase the risk of malnutrition among already vulnerable infants from food insecure families.” They recommended either increasing access to antiretroviral therapy (ART) for breastfeeding women or providing specialised replacement feeding for the infants.

Higher mortality associated with early weaning in Uganda

In fact, preliminary data from a Ugandan study, also reported troubling findings related to early weaning in mothers on antiretroviral therapy. The study found that although mothers who used antiretroviral therapy were less likely to pass on HIV than women with less advanced HIV who only took single-dose nevirapine (sd-NVP), they were also far more likely to wean earlier than women who merely took sd-NVP.

This likely contributed to the lower rate of HIV transmission but the infants who were born to the women on ART also had a higher rate of mortality. According to the study’s abstract, eleven in the ART group versus three in the non-ART group died (RR=1.61 p

Severe diarrhoea outbreak in Botswana

But the provision of “suitable” alternative foods can also go wrong. For example, in Botswana, the wealthiest country in sub-Saharan Africa where quality replacement formula is freely provided to HIV-exposed infants, a major outbreak in severe diarrhoea has claimed the lives of hundreds of children. The outbreak mostly in northern Botswana involved over 10,000 infants (HIV-infected and uninfected) and caused at least 200 deaths.

But the source wasn't cholera, or anything that the laboratories in Botswana could easily identify. So the country had called in experts from the US Centers for Disease Control (CDC) for assistance, and they concluded that the outbreak was caused by a gastroenteric virus.

However, the CDC team made one key observation — that infants who were formula fed (regardless of whether they were HIV-infected or not) were much more likely to develop diarrhoea and to die from it.

Prevention studies in Botswana have demonstrated that treatment for PMTCT and early breastfeeding have led to a dramatic reduction in HIV transmission — and yet many HIV-exposed infants are still in poor health. In addition to the diarrhoea outbreak, researchers found that acute malnutrition and growth failure have been common among formula fed infants. This raises questions about the safety of formula feeding and points out the need for very close monitoring of infant feeding programmes.

Its possible that support for better sanitation — boiling water and feeding infants from a cup (which can be more easily sterilised than a bottle) could help avoid some of the diarrhoea. However, given that breastfeeding has a protective effect against diarrhoea in children, the findings could also suggest the health costs of early weaning outweigh the benefit of preventing HIV infection — and that programmes need to evaluate infant mortality and morbidity over long term.