Among the people socializing in a tavern in Alexandra township in Johannesburg is Karabo Sathekge, who asked that VOA not give her real name. She is a slight, attractive 19-year-old in a veil of an orange dress, defying the winter chill.
Sathekge often meets one of her partners here. He is more than twice her age.
Sathekge explains that sex with older men is sometimes "rough," and always without a condom.
South Africa has almost 7 million people living with HIV and manages the globe's largest antiretroviral program, keeping about 4 million people alive with the drugs. At the South African National AIDS Conference in Durban this week, specialists voiced their concern about the spiking rates of infections among young women, a trend reflected throughout the continent.
"What does it tell you about the lack of knowledge about HIV, 20, 30 years into the HIV epidemic?" said Mark Heywood, the director of the Section 27 social justice movement. "We have seen, shockingly, a decline in knowledge of HIV amongst young people. It is like we have taken our foot off the accelerator, in certain respects."
Heywood says more than 200 young women, ages 15 to 24, are infected with HIV each day in South Africa.
In 2015, that demographic accounted for the largest segment of new HIV infections in South Africa and a disproportionate number of new cases in the region. Adolescent and young women made up a quarter of the new cases in sub-Saharan Africa, according to UNAIDS most recent global report.
UNAIDS says adolescent and young women in Africa are at "particularly high risk" for a variety of reasons, such as poverty, lack of education and violence.
Like Sathekge, many poor young women in South Africa have "transactional" sexual relationships with older men who have jobs and money. The men buy them food, clothes and gifts.
Health care workers in South Africa say transactional sex is a key driver of the new infections among young women in the country.
Heywood is at the forefront of protests to demand the government make a new weapon against HIV infection available to young women. That weapon is a combination of antiretroviral drugs called "pre-exposure prophylaxis," or Prep. Taken correctly, the pill can prevent people from getting HIV.
Heywood says the state could afford to give the drugs to young women for free.
"If you have literally tens of billions of rand being stolen every year out of different government departments, that is money that could be generating programs that reduce the vulnerability of young women," he said. "But there has to be a [political] will."
South Africa's health minister, Aaron Motsoaledi, says he plans to provide Prep to young women in about two to three years, after educating them about the pill. It must be taken at about the same time every day, and ideally is used with condoms.
However, Heywood says Motsoaledi's "innovative" policies to prevent new HIV infections are likely to stall, as Motsoaledi has been politically isolated after publicly opposing President Jacob Zuma over Zuma's alleged corruption.