Africa's AIDS epidemic may not have been fuelled mainly by sexual transmission of the HIV virus but by unsafe medical injections and blood transfusions, a team of international researchers say.
The findings contradict widely-held views about how the virus that causes AIDS spread through Africa, and could have implications for public health measures to fight the disease.
Most scientists believe heterosexual sex spreads HIV/AIDS in up to 90 percent of adult cases in sub-Saharan Africa, home of 30 million of the 42 million people living with the disease.
But a team of eight experts from three countries who reviewed data on HIV infection in Africa estimate only about a third of adult cases are sexually transmitted. They said healthcare practices, especially contaminated medical injections, could also be a major cause.
"The idea that sex explains 90 percent of African HIV just doesn't fit the facts," said David Gisselquist, a Pennsylvania-based independent consultant and member of the research team.
"We need to take a look at the alternate explanations, in particular healthcare transmissions which seems to fit a lot of facts," he added in a telephone interview with Reuters.
The findings, reported in the International Journal of STD & AIDS, a peer-reviewed journal published by Britain's Royal Society of Medicine, were not accepted by all scientists.
"The idea that dirty needles or blood transfusions are the main route for HIV transmission in Africa today, flies in the face of experience on the ground," said Dr Chris Ouma, head of health programmes at the charity ActionAid Kenya.
The WHO and UNAIDS, the United Nations agency spearheading the global battle against HIV/AIDS, will hold a meeting in Geneva on March 13-14 to address the issue of unsafe injections.