Adolescent girls and young women in Uganda are experiencing a significant decline in new HIV infections, driven by a combination of behavioral changes and expanded access to medical interventions, according to a new study.
The research, published in PLOS Medicine, found that HIV incidence among women aged 15 to 24 dropped by an estimated 71 percent between 2000 and 2019, marking one of the most substantial public health gains in recent decades.
Researchers attribute this progress to a mix of factors, including delayed sexual debut, increased access to antiretroviral therapy (ART), and the scale-up of voluntary medical male circumcision (VMMC).
“Both biomedical HIV interventions and broader behavioral changes contributed to declines in HIV incidence,” the authors noted.
Among younger adolescents aged 15 to 19, delaying the age at which individuals first engage in sexual activity emerged as the most influential factor. Over the study period, the average age at first sex increased by approximately three years for young women, significantly reducing their exposure to HIV risk.
“Increasing age at first sex was the largest contributor to incidence declines among adolescent women,” the study found.
For slightly older women aged 20 to 24, however, the expansion of HIV treatment played a more dominant role. ART, which reduces the amount of virus in the body and lowers the likelihood of transmission, was identified as the leading driver of reduced infections in this group.
Meanwhile, male circumcision, known to reduce men’s risk of acquiring HIV, also contributed to the overall decline, though its effects were more gradual. “VMMC contributed modestly to historical declines but had larger projected effects over longer time horizons,” the study noted.
Importantly, the research highlights that these interventions did not work in isolation. Instead, their combined impact was greater, with each factor reinforcing the others as ART, VMMC, and delays in age at first sex acted additively to reduce HIV incidence.
The findings are based on long-term data from the Rakai Community Cohort Study, one of Uganda’s most comprehensive HIV surveillance programs, combined with advanced mathematical modeling to assess trends and predict future outcomes.
Despite the encouraging progress, researchers caution that continued success will depend on sustained investment in both prevention and treatment strategies.The study also underscores the importance of broader social changes, such as increased access to education, which may be contributing to delayed sexual activity and reduced vulnerability among young women.
Photo Credit: UNICEF