This article appears in the Witness section of the Autumn 2017 issue of the New Humanist. Subscribe today.

Although HIV is no longer the death sentence it once was, people infected with the virus usually need treatment every day to prevent it attacking their immune system and causing Aids.

In South Africa doctors have announced that a nine-year-old infected with HIV at birth has spent most of their life without requiring this daily treatment – or any treatment at all. The child, whose identity is being protected, was given a burst of treatment shortly after birth. Early antiretroviral therapy wasn’t standard practice at the time, and was given to this child as part of a clinical trial. The child, who caught HIV from their mother, had very high levels of the virus in the blood and was given the treatment from the time they were nine weeks old. Treatment was stopped after 40 weeks, when levels of the virus were undetectable. It has not returned.

The child has now been off drugs for eight and a half years, with no symptoms or signs of active virus. Understanding why this child has been protected could help the development of new drugs, or a vaccine for stopping HIV.

This is not the first example of HIV being stopped through early therapy for a child. There was a case in France where the patient went more than 11 years without drugs, and the “Mississippi baby”, treated within 30 hours of birth, who went 27 months without treatment before HIV re-emerged.

These cases are rare, and it is impossible to extrapolate a simple solution from these small successes. Other children who took part in the South African study did see the virus re-emerge, so it is not a case of simply treating HIV early. “We don’t believe that antiretroviral therapy alone can lead to remission,” said Dr Avy Violari, the head of paediatric research at the Perinal HIV Research Unit in Johannesburg. “We don’t really know what’s the reason why this child has achieved remission – we believe it’s either genetic or immune-system-related.”

While individual cases such as this must not detract from the fact that only 53 per cent of the 36.7 million people with HIV worldwide have any access to antiretroviral therapy at all, it does offer a further avenue for inquiry and research in the slow march towards a cure.