A nine-year-old child in South Africa has possibly become the third case of a child in remission from HIV after antiretroviral therapy only during infancy.

The case was reported by doctors at the Perinatal HIV Research Unit in the Faculty of Health Sciences, University of the Witwatersrand on July 15 at the International AIDS Society Conference in Paris.

The child had been part of a trial called Children with HIV Early Antiretroviral Therapy conducted by the team of doctors. in the trial HIV-infected infants were randomly assigned to receive one of three treatments – either deferred antiretroviral therapy or early limited antiretroviral therapy for 40 or 96 weeks.

The child was born to an HIV-infected mother in 2007 and was diagnosed as HIV positive with very high viral loads when it was just 32 days old. At about nine weeks of age, the child was given antiretroviral therapy that suppressed the virus to undetectable levels. As per the protocols of the randomised trial, the investigators halted treatment after 40 weeks. They monitored the child’s immunity and and saw that the child has remained in good health during years of follow-up examinations.

Recent analyses of stored blood samples taken during the child’s follow-up examinations show that the child has maintained undetectable levels of HIV-1 since its treatment was stopped when it was just an infant. Investigators detected a viral reservoir that had integrated into a small proportion of the child’s immune cells but otherwise found no evidence of HIV infection. The child had a healthy level of key immune cells, a viral load that was undetectable by the routine laboratory diagnostic tests, no symptoms of HIV infection and no replication competent virus.

The child also did not have genetic characteristics previously associated with spontaneous control of HIV in adults, suggesting that the 40-week antiretroviral therapy provided during infancy may have been key to achieving HIV-1 remission in this case.

“We believe there may have been other factors in addition to early ART that contributed to HIV remission in this child,” said Professor Caroline Tiemessen, the senior author of this case and Research Professor in Virology in the School of Pathology at Wits University.

The researchers have called for further investigations into the child’s immune system mechanisms to expand understanding of how it controls HIV replication.