(CNN) -- It's a potential game changer in the fight against HIV, and doctors say it happened almost by accident.
A baby with the virus that causes AIDS was given high doses of three antiretroviral drugs within 30 hours of her birth. Doctors knew the mother was HIV positive and administered the drugs in hopes of controlling the virus.
Two years later, there is no evidence of HIV in the child's blood.
The Mississippi girl is the first child to be "functionally cured" of HIV, researchers announced Sunday. They said they believe early intervention with the antiretroviral drugs was key to the outcome.
A "functional cure" is when the presence of the virus is so small, lifelong treatment is not necessary and standard clinical tests cannot detect the virus in the blood.