Every year 600,000 babies worldwide are infected with HIV, usually at birth or through breast-feeding. The four-pronged standard of care in the U.S. is to prevent transmission by suppressing the pregnant mother's virus with HAART, a C-section birth, meds for the baby and the substitution of formula for breast milk. But HAART is too expensive for wide use in poor countries, where women often breast-feed their babies for long periods either as a custom or as a last resort against starvation. What they need is cheap prevention that fits their circumstances.

Since the '90s, researchers have sought solutions. One of the most significant studies, the UNAIDS-funded Perinatal Transmission (PETRA) study, gave one group of pregnant women in five urban hospitals in South Africa, Uganda and Tanzania an AZT/3TC combo from the 36th week of pregnancy through labor, as well as seven days postpartum dosing to child and mother. The results, published in the April Lancet, showed that while the meds were very effective at blocking HIV at birth, the benefits vanished after 18 months of breast-feeding. In fact, these infants fared no better than their peers who got no HAART at all. That babies who are breast-fed by positive moms eventually lose the meds' viral protection is very distressing news, especially given the options. If moms don't breast-feed, their kids go hungry. And even when a woman can afford formula, she still may not have clean water to mix it with -- not to mention that using formula can mark her as HIV positive, putting their life in danger.

Mother to Child Transmission Plus (MTCT+) programs, which give positive women an ongoing course of HAART -- as soon as they know they are preggers, through breast-feeding and beyond -- is the only feasible panacea as drug prices fall and demand rises.