When the expectant Mississippi mother, already in labor, arrived at the University of Mississippi Medical Center in 2010, she had no idea she would be making history. She had no prenatal care during her pregnancy and had no idea that she was HIV positive, much less that she could pass the virus to her child.

Because she had not taken advantage of prenatal drug therapies that can cut the risk of passing the infection from mothers to newborns from 25% to less than 2%, her doctor took a chance. She started the infant on potent antiretroviral medications (ARVs) that have been responsible for extending the lives of millions of HIV-positive adults. Normally, babies are given a preventive regimen of one or two of these drugs for the first six weeks of life, on a just-in-case basis to ward off infection. But in this instance, with such a high risk of mother-to-child transmission, Dr. Hannah Gay decided to be more aggressive, starting the newborn, just 30 hours after birth, on a three-drug regimen normally reserved for adults.

Much to Gay’s surprise and that of the AIDS community, the now 2½-year-old toddler remains free of the HIV that was present at birth and doesn’t need to rely on any anti-HIV drugs. A single case hardly constitutes a cure, but reports of the child’s condition are stoking optimistic discussions about how an endgame for the worldwide epidemic might play out.

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