“Starting in the mid-2010s, the University of Oxford pediatrician and immunologist began working with scientists in the South African province of KwaZulu-Natal, with the aim of tracking several hundred children who had acquired HIV from their mothers, either during pregnancy, childbirth, or breastfeeding.

After putting the children on antiretroviral drugs early in their lives to control the virus, Goulder and his colleagues were keen to monitor their progress and adherence to standard antiretroviral treatment, which stops HIV from replicating. But over the following decade, something unusual happened. Five of the children stopped coming to the clinic to collect their drugs, and when the team eventually tracked them down many months later, they appeared to be in perfect health…

Goulder is now launching a new study to try and examine this phenomenon in more detail, taking 19 children in South Africa who have suppressed HIV to negligible levels on antiretrovirals, stopping the drugs, and seeing how many can prevent the virus from rebounding, with the aim of understanding why. To date, he says that six of them have been able to control the virus without any drugs for more than 18 months. Based on what he’s seen so far, he has a number of ideas about what could be happening. In particular, it appears that boys are more likely to better control the virus due to a quirk of gender biology to do with the innate immune system, the body’s first-line defense against pathogens.”

From Wired.