Current beliefs about the spread of HIV in sub-Saharan Africa may be unfounded, according to a paper published recently by two Brown researchers.
Assistant Professor of Community Health and Medicine Mark Lurie and Samantha Rosenthal GS, a masters student in public health, found that there is insufficient scientific evidence to prove that concurrency — the practice of having multiple sexual relationships at the same time — is the main driving force behind the HIV epidemic in sub-Saharan Africa.
"We've challenged an otherwise unchallenged assumption about the impact that overlapping sexual partners has," Rosenthal said.
The prevailing assumption that concurrency is driving the epidemic, Lurie said, is "a great big leap of faith."
About one year ago, Lurie read an article by Harvard public health researchers Timothy Mah and Daniel Halperin that presented the evidence supporting the central role of concurrency in HIV transmission.
"I did not feel like there was strong evidence at all," Lurie said.
"A lot of problems or shortcomings (of the concurrency theory) were not mentioned or identified," Rosenthal said. "The evidence at best is mixed."
Lurie and Rosenthal concluded that the cause of the HIV epidemic could not be traced back to one factor.
Though Lurie and Rosenthal do not deny that concurrent sexual relationships can play a role in propagating HIV, poverty, migration, lack of circumcision and lack of access to health care and education also affect the epidemic, they said.
"We are not saying that (concurrency) is not important or … is not happening," Lurie said, "but the hypothesis that's out there that people are taking as fact is flawed in many ways."
The United States Agency for International Development has recently spent millions of dollars on mass media campaigns to discourage concurrent sexual networks in sub-Saharan Africa, the researchers said.
Rosenthal and Lurie are wary of pulling money from tried and true methods of preventing the spread of HIV — like condom use and circumcision — to funnel into discouraging concurrency.
"Money may well have been spent better elsewhere on an intervention that we already know is efficacious," Lurie said.
Both Lurie and Rosenthal said they wanted to force people to think a little more carefully about how HIV spreads and not jump to conclusions.
"There are still a lot of question marks," Lurie said.
The pair wants to discourage non-profit organizations and policy makers from rushing to tackle concurrency until they have more evidence.
"We want to encourage better study and research, agree upon consistent definitions of concurrency and then do research and multiple studies to show that this is going on," Rosenthal said. "We need to ask, ‘What do we know?' and realize that we need to do more work."
