A child who was said to have been cured of human immunodeficiency virus last year has developed an HIV infection and been put back on antiretroviral drugs after remaining off of them for 27 months, dashing hopes of a new treatment for infants.
Doctors announced Thursday that traces of HIV were detected in the child last week during regular testing that she undergoes every six to eight weeks.
The discovery was disappointing, doctors said on a conference call, because they hoped the aggressive treatment regimen that helped abate the child’s HIV could lead to a cure in infants.
“It felt very much like a punch to the gut,” said Dr. Hannah B. Gay, a pediatric HIV specialist at the University of Mississippi Medical Center who treats the girl. “It was disappointing from the scientific standpoint because we had been hopeful it would lead to bigger and better things, but mainly for the sake of the child who is back on medicine and expected to remain on medicine for a very long time.”
Dr. Katherine Luzuriaga, an immunologist at the University of Massachusetts Medical School who is part of the girls’ medical team, said during a conference call that tests show the child is responding well to drug therapy.
HIV hides in so-called reservoirs of the body, and the viral material there often remains dormant as long as a patient is receiving antiretroviral drugs. But as soon as the drugs are stopped, the viral strains can become active and replicate in the body.
Outside experts said the findings are still critical in advancing HIV treatment. Though more research is needed, the “Mississippi baby” case shows that early, aggressive therapy can be effective in reducing reservoirs in the body, especially because she remained free of replicable HIV for more than two years — a landmark finding.
The child’s mother delivered her in a rural Mississippi hospital in 2010 but did not know she was infected with HIV. She did not undergo treatment during her pregnancy, so the baby was transferred to University of Mississippi Medical Center when she was about 30 hours old after doctors thought she could have been infected.
Gay used a three-drug regimen instead of the typical one or two drugs for a newborn. The child showed undetectable levels of HIV after a month but continued to take antiretroviral drugs until she was 18 months old. Her mother then stopped bringing her to the hospital and ceased the drug treatment.
When the child returned to the hospital five months later, Gay and Luzuriaga ran a battery of tests and found some viral genetic material but no replicable strains lying in reservoirs, leading them to believe the girl had been “functionally cured.”
The case is familiar for Dr. Timothy Henrich, a Brigham and Women’s Hospital infectious diseases associate physician. Henrich led a team of Boston researchers studying two patients who had become HIV-free after undergoing bone marrow transplants for cancer but were later found to have detectable levels of the disease.
“It was almost a little bit of PTSD and déjà vu for me,” Henrich said. “When I first read the news, my heart sank. . . . The most difficult thing I had to do as part of our study was tell [the patients] the virus had returned.”
The discovery that the Mississippi baby has developed viremia — an active infection — highlights how much more there is to learn about these reservoirs, said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases.
Some outside experts doubted whether the child ever had been infected with HIV, when doctors announced she had been cured last year. The girl’s doctors said discovering viremia shows she was infected, but they effectively eliminated the HIV in the child, even if not permanently.
“This was unprecedented,” Dr. Deborah Persaud, professor of infectious disease at Johns Hopkins Children’s Center and the lead author of the original report on the baby last year, said of the child successfully staying off antiretroviral drugs for 27 months. “The most important finding is indeed, this child was, without a doubt, infected with HIV.”
There is only one person believed to have been cured of HIV. In 2009, German doctors reported that Timothy Ray Brown, an American known as the “Berlin patient,” received a bone marrow transplant from a patient with a rare genetic mutation that is thought to provide resistance to HIV.
The Berlin patient was an exceptional case because of the rare mutation that came from the marrow donor, Henrich said.
Even with very low levels of viral material, there is always the risk HIV can reemerge at detectable levels.
The Mississippi case “was a seminal study that was very important and did teach us a lot and is still teaching us a lot,” Henrich said. “It’s still worthwhile to pursue this research.”
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