YOUNG women between the ages of 16 and 23 years are being infected with HIV by men around eight years their senior.
Wits Reproductive Health Institute research director Sinead Delaney-Moretlwe said these men were often also sexually involved with women of their own age, who in turn may have become infected when they were younger. In this way, age-disparate relationships are fuelling the epidemic.
At a forum held in Cape Town this week, leading researchers, policymakers, programme implementers and young people from the region gathered in Cape Town to discuss the key group.
The forum was hosted by the UK-funded Evidence for HIV Prevention in Southern Africa programme.
Statistics showed almost one in four new HIV infections in eastern and southern Africa are among young people aged 15 to 24, and two-thirds of these were girls.
Although boys and young men are statistically less affected, deaths from Aids in this age group have increased since 2010.
Delaney-Moretlwe said if interventions were not introduced now, the epidemic could not be controlled.
This crisis requires a new approach to adolescent HIV prevention.
But the real world challenges are immense – from entrenched risky behaviour patterns to weak health systems, experts say.
Desmond Tutu HIV Foundation socio-behavioural scientist Laura Myers said it was working with men to address this issue, which included encouraging responsible parenting, and highlighting the risks of alcohol abuse and having multiple partners. She said sexual violence also needed to be addressed.
“Good work with men is needed to shift social norms,” she said.
The foundation's Linda-Gail Bekker, head of the International Aids Society, said it would take more than just health interventions to beat youth HIV.
“We are trying to prevent something, but what we really need to do is to deliver a healthy society. If society is dysfunctional, disease feeds on that,” she said.