Kyeen Mesesan used statistical modeling to determine how many new HIV infections adult male circumcision could prevent in a township in South Africa.

“A surgery to prevent HIV”

Since Kyeen Mesesan, an M.D./Ph.D. candidate at the School of Medicine, began her dissertation project in South Africa in 2003, she has received accolades and invitations to present at conferences. But nothing was quite like the 16th International AIDS Conference in Toronto in August, where she presented a paper on adult male circumcision programs and HIV.

“I had an idea it would be a bit contentious,” said Mesesan. “We’re talking about a surgery to prevent HIV.” Indeed, activists at the conference raised pointed questions about genital mutilation, race and gender. But the idea has gained currency as the notion of a single magic bullet against AIDS gives way to multiple measures to prevent HIV infection.

Circumcision was not originally part of Mesesan’s research—she was exploring a hypothetical question. “What does a country like South Africa do 10 years from now if a partially effective vaccine comes out—say 30 percent effective—and they have to decide whether they’re going to use it on their population?” she asked. Mesesan put this question in the context of other risk factors, such as sexual behavior and condom use. “Although in most scenarios such a low-efficacy vaccine would be beneficial, in some scenarios you could actually make the epidemic worse.”

Her research took a detour in July 2005 when, in a study in South Africa, French researchers linked male circumcision to a 61 percent reduction in female-to-male transmission of the virus. Mesesan took that number and, applying statistical modeling techniques, estimated that in the township of Soweto, a five-year prevention program that boosted the current 35 percent circumcision rate by 10 percent would prevent 53,000 infections.

“While even a low-efficacy HIV vaccine may be decades away, circumcision is effective and the technology is available immediately,” Mesesan stated. In December trials in Kenya and Uganda showed that circumcision reduced the risk of AIDS from heterosexual sex by half.

—John Curtis