The Breast Solution: Nature's Nutrition Keeps HIV at Bay
Barry, Caroline, Science News
HIV, the virus that causes AIDS, is ravaging Africa. In some regions south of the Sahara Desert, more than 35 percent of the population is infected. Each year, as many as 700,000 children acquire HIV from their infected mothers during pregnancy, labor, or breast-feeding.
In developed countries, by contrast, mother-to-child HIV transmission has been virtually eradicated. Pregnant women take anti-HIV drugs to minimize the chance of passing the virus to their babies. Delivery by cesarean section removes the danger of HIV reaching a baby during birth. And use of infant formulas eliminates the possibility of infection through a mother's breast milk. As a result, fewer than 2 percent of babies born to HIV-positive mothers in developed countries become infected.
But in Africa, up to 40 percent of the children of HIV-infected mothers are either infected at birth or become infected soon afterward. Cesarean sections are too risky or simply unavailable in many African hospitals, and the World Health Organization (WHO) estimates that only 9 percent of pregnant HIV-infected women in subSaharan Africa receive anti-HIV drugs.
Moreover, researchers have concluded that a significant number of African babies acquire HIV infection through the very substance that protects them in so many other ways: breast milk.
"We already know how to prevent breast-feeding transmission: Don't breast-feed," says Lynne Mofenson of the National Institute of Child Health and Human Development in Bethesda, Md. But that ideal is "not an option in [developing] countries."
In the developed world, with an abundance of clean water and easy access to medicines and health services, feeding infants on formula presents no unusual difficulties or dangers. But in Africa, where food may be scarce and women sometimes can't afford enough formula or don't have access to clean water, many infected women have tried to heed WHO advice to bottle-feed their newborns but have ended up supplementing their children's diets with breast milk.
Now, research is revealing a cruel irony. This part-formula-part-breast regimen may be the worst strategy of all for the babies it's supposed to protect. Recent studies show that supplementing breast milk with other food exacerbates the risk of HIV transmission from mother to child in several ways. In addition, babies don't get the full nourishment and disease-preventing benefits of breast milk, while being exposed to heightened risks of malnutrition and gastrointestinal diseases from inadequate formula and the polluted water with which it's sometimes mixed.
On the basis of mounting anecdotal evidence and, now, a large and lengthy study of HIV and breast-feeding, many researchers and health authorities have concluded that women in developing countries should return to feeding babies only breast milk in order to reduce their chances of HIV infection as well as save them from a host of other ills.
BREACHING THE BARRIER Studies have shown that children whose infected mothers don't get antiretroviral drugs or other interventions during pregnancy have a 15 percent to 25 percent chance of acquiring HIV before or during birth. If the child of an infected mother is fortunate enough to make it into the world HIV-free, he or she still has an additional 5-to-20 percent chance of picking up the virus through breast milk. The longer an infected mother breast-feeds, the greater the chance that she will give the virus to her child, studies show.
Viruses such as hepatitis B and hepatitis C can't pass through breast milk, but HIV finds a way. Some 45-to-60 percent of breast-milk samples from HIV-infected women contain the virus, researchers have found. A baby won't be barraged with HIV every time it breast-feeds, but since a child takes milk several times a day, each baby of an infected mother is presumed to be regularly exposed to HIV.
Further increasing the likelihood of HIV transmission are various types of tissue damage. …