A four-year-old girl born with HIV, who was believed have been “functionally cured” of the virus, is no longer in remission, doctors have said.
In March, medical professionals said that the unnamed Mississippi girl seemed free of the virus despite not having been on drugs for about two years – a medical first.
It was hoped that early treatment with aggressive drugs would show that the virus could be setback after taking hold.
The girl, who has once again tested positive for the virus, is now back on treatment and is responding well, doctors said.
Dr Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases, said the news is “obviously disappointing” and that it could have implications on a US study which is due to trial early, powerful treatment on those with HIV.
There are ethical concerns over raising false hopes on a method that has suffered a setback.
“We're going to take a good hard look at the study and see if it needs any modifications,” Mr Fauci said, possibly in terms of length and type of treatment.
When pregnant, the child’s mother had received no medicines, which she was entitled to.
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Instead, the virus was detected during labour – leading to doctors administering the powerful drugs to the newborn when she was 30hrs old.
Doctors continued to treat the girl until she was 18 months old, when they lost contact with her. When she returned, 10 months later, they were stunned to find that there was no trace of the virus in her, despite her mother stopping the medication.
The girl’s HIV was undetectable until last week, leading doctors to believe that more needs to be understood about where the virus hides in the body.
"The case of the Mississippi child indicates that early antiretroviral treatment in this HIV-infected infant did not completely eliminate the reservoir of HIV-infected cells that was established upon infection but may have considerably limited its development and averted the need for antiretroviral medication over a considerable period," Dr. Fauci said, according to The Verge.
"Now we must direct our attention to understanding why that is and determining whether the period of sustained remission in the absence of therapy can be prolonged even further."
Additional reporting by agencies