A Mississippi baby born infected with HIV who was treated shortly after birth and believed to be cured was discovered to still have the virus.

Doctors announced on Thursday that the nearly 4-year-old girl was never truly cured, but merely had levels of the virus reduced so low it was merely undetectable, according to the Los Angeles Times. The levels have unfortunately rebounded after two years and a long period of non-treatment.

"It felt very much like a punch to the gut," pediatric HIV specialist Dr. Hanna Gay, of the University of Mississippi Medical Center, said. "It was extremely disappointing."

The girl was born prematurely in 2010, and Gay treated the child with a cocktail of three HIV drugs, Reuters reports. The doctor hoped that a more aggressive course of action might help fend off HIV, and after an additional 18 months of treatment, the young girl was thought to be cured.

With the "Mississippi Baby" no longer truly cured, all eyes turn towards a baby born in California that was treated in the same aggressive manner and has appeared to be clean through nine months of continued treatment.