Paris (AFP)

The number of adolescents aged 15-19 who have been treated for HIV has increased tenfold in South Africa over the past decade, but fewer than half of those presenting for care begin treatment, researchers say.

South Africa is considered the country with the largest number of people living with the AIDS virus, approximately 7.2 million.

But "the fight against the epidemic in South Africa will require a significant expansion of treatment of adolescents to break cycles of HIV transmission and reach the promise of a generation without AIDS," warn researchers in the journal The Lancet HIV who publishes their study Wednesday.

In 2016, about 10.2 million adolescents aged 10 to 19 lived in this country.

The increase in the number of adolescents on treatment is partly due to the historic success of the anti-retroviral treatment program in South Africa.

The authors analyzed data on 730,882 patients aged between 1 and 19 who participated in the HIV program between 2005 and 2016. Among patients admitted before the age of 15, 54% were girls (209,205 patients), infections were contracted during birth or during breastfeeding involving approximately the same sex.

Among patients aged 15 to 19 years (301,242 patients), 88% were women. The latter, in fact, have much higher rates of sexual infection and demands for care than young men.

The number of 15 to 19 year olds starting antiretroviral therapy increased from 7,949 patients between 2005 and 2008 to 80,918 between 2013 and 2016.

But the proportion of HIV-positive adolescents who start treatment is lower than in children. Only 45% of girls aged 15 to 19 and 42% of HIV-positive boys started treatment, compared to 68% of girls and 69% of boys aged 1 to 4 years.

According to the researchers, these results underscore "the importance of preparing South African health systems to provide effective HIV care to a growing number of adolescents".

© 2019 AFP