If the findings in the new case bear up under further scrutiny, it will mark the first time the infection has been cured by drugs. The only known cure of a case of HIV infection occurred in 2007. An American man living in Germany got a bone-marrow transplant from a donor who had a rare HIV-resistance mutation in his cells.
“We are calling this a ‘functional cure,’ ” said Katherine Luzuriaga, a physician at the University of Massachusetts Medical School, who was involved in the baby’s care. “Time and further investigation will tell us whether this child actually has been cured or not.”
Researchers provided no personal details about the case, not even the sex of the infant.
Word of the case was being greeted with interest and skepticism by researchers, who have seen many other reports of cure prove false when examined closely or tried again.
“It’s a hypothesis-generating case,” Anthony S. Fauci, head of the National Institute of Allergy and Infectious Diseases, said of the Mississippi case. “It will give us some food for thought about studies that need to be done to see if this is a real phenomenon.”
Treating a newborn with the life-extending combination of drugs known as “triple therapy” is almost never done.
The reason is that it is difficult to determine immediately after birth whether a baby is infected. Antibodies from an HIV-infected mother spill into the baby’s circulation, giving a positive test for weeks. Infants are not started on the drugs until at least six weeks after birth, when infection is certain.
Mother-to-child HIV transmission is extremely rare in the United States. Fewer than 200 cases occur each year. For more than 15 years, virtually all pregnant women known to be infected have been given antiretroviral drugs during pregnancy and labor. Their babies get one or two drugs for at least six weeks after birth — a strategy that cuts the risk of transmission to less than 5 percent.
In the Mississippi case, however, the mother arrived at the hospital without prenatal care. When a screening test for HIV came back positive, “she was too near delivery to give even the dose of medicine that we routinely use during labor,” Hannah Gay, a pediatrician at the University of Mississippi Medical Center in Jackson, wrote in a short narrative of the events provided to a reporter.
Because of the baby’s unusually high risk of having been infected, Gay and her colleagues started full triple therapy 30 hours after birth.
HIV tests of the infant’s blood over the next three weeks were repeatedly positive. The virus could have been from the mother, although such spillover is usually cleared quickly by the baby. Instead, the amount of HIV — the “viral load” — declined steadily over time, as happens in adults with long-established infections when they are started on triple therapy. By 29 days after birth, the baby had no detectable virus, which is the goal of treatment.