A four year-old girl thought to have been cured of the AIDS virus shows signs that she still has it.
The little girl was born in the southern U.S. state of Mississippi to an HIV-positive mother, whose status was discovered when the girl was born.
Doctors almost immediately began treating the baby with a powerful dose of AIDS drugs.
The treatments stopped after 18 months, but the girl showed no signs of HIV until last week, when the virus was detected in her blood.
Dr. Anthony Fauci, head of the U.S. Institute of Allergy and Infectious Diseases, says the re-emergence of the HIV is disappointing.
But he said researchers will look into how the early treatment may have limited the development of the virus.