Elite controllers: people who control HIV without medicine ^{CEFR B2}

A small group of people with HIV, known as elite controllers, can keep the virus at undetectable levels without antiretroviral therapy. They represent about one in 200 people living with HIV. Scientists hope that understanding how their immune systems control the virus could lead to new treatments, or possibly a cure, and might also help against other viral diseases.

Thumbi Ndung'u, director for basic and translational science at the Africa Health Research Institute and a professor at the University of KwaZulu-Natal, told SciDev.Net that elite controllers appear to have a superior antiviral immune response. He added that the mechanisms that keep the virus in check are varied and not yet fully understood. A person is generally defined as an elite controller after living with an undetectable viral load for at least two years without ARVs; for some the suppression lasts a lifetime, while for others the viral load later rises and antiretroviral therapy is then strongly recommended.

Researchers are particularly interested in genetic factors in African populations. The HIV Host Genome project aims to identify any distinct genetic traits in African elite controllers; teams have already found some genes involved in immune control that were seen elsewhere and plan to extend the work to find other factors. Individuals such as Sandra Harrigan-Thompson have joined studies and donated samples; she described her blood as a gift for future generations.