A Mississippi girl born with acquired immune deficiency syndrome (AIDS) is no longer cured after she showed signs of human immunodeficiency virus (HIV), the Associated Press reported Thursday. The young girl, now 4, was in remission for years without any treatment.

The child became known as “Mississippi baby,” whose apparent cure was reported in The New England Journal of Medicine, last fall, USA Today wrote.

In March, the young girl received news of a medical first. Doctors said she didn’t show signs of HIV even though she hadn’t been on AIDS drugs for two years.

On Thursday, doctors said she was no longer in remission and was put back on drugs. They said she was “responding well” to the medicine.

"Certainly, this is a disappointing turn of events for this young child, the medical staff involved in the child's care and the HIV/AIDS research community," Anthony Fauci, director of the National Institute of Allergy and Infection Diseases, said at the briefing, according to USA Today.

But the development "reminds us that we still have much more to learn about the intricacies of HIV infection and where the virus hides in the body," Fauci said in a statement. "The NIH remains committed to moving forward with research on a cure for HIV infection."

Aside from the “obviously disappointing” news, it may also affect a federal study on testing and aggressive treatment in cases like the Mississippi young girl, Fauci added.

"We're going to take a good hard look at the study and see if it needs any modifications,” Fauci said, in reference to length and type of treatment as well as the ethics, as it has created false hope through an approach that has now had a setback.

Typically, HIV-infected mothers in the U.S. receive AIDS treatment during pregnancy, which greatly decreases the chance they will pass the virus to their child. But the Mississippi baby’s mother didn’t know she had HIV. It wasn’t discovered until she was in labor, so she didn’t have any prenatal care.

The baby was given aggressive treatment 30 hours after she was born, even before tests could determine if she was infected. The child was treated until she was 18 months old, and then doctors lost contact with her. When she returned 10 months later, they could not find any signs of the infection, even though her mother stopped giving her the AIDS medicine.

Tests came up negative until last week, when copies of the virus were measured in her blood. Doctors are unsure why the virus came back and now have new questions about their current knowledge of HIV hideouts in the body.

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