Researchers Pinpoint Origin of HIV Pandemic: First Human Case Was Probably in Kinshasa Around 1920

HIV origins pinpointed
A HIV-positive patient receives medicine through an intravenous drip at Medecins Sans Frontieres Holland's clinic in Yangon March 3, 2014. Minzayar/Reuters

A group of researchers from Oxford University and the University of Leuven say they have pinpointed the place where HIV was first transmitted between humans, sparking a pandemic that would go on to touch some 75 million people in every corner of the globe. Through statistical analysis, the group determined that HIV is "almost certain" to have begun its spread from Kinshasa, now the capital city of the Democratic Republic of Congo, sometime around 1920.

The research team analyzed all available HIV-1 viruses sampled from infected persons between 1985 and 2010 to trace the outbreak back to their shared ancestry in a group of infected individuals referred to as "group M" who they say became infected in Kinshasa.

The geographic spread of a virus, coupled with growth of the infected population, leave "a measurable imprint" on the HIV genomes found in the various samples, explains Nuno Rodrigues Faria, a researcher at Oxford University and an author on the paper.

"Until now most studies have taken a piecemeal approach to HIV's genetic history, looking at particular HIV genomes in particular locations," Oliver Pybus, a professor at Oxford University and a senior author of the paper said in a press release. "For the first time we have analysed all the available evidence using the latest phylogeographic techniques, which enable us to statistically estimate where a virus comes from. This means we can say with a high degree of certainty where and when the HIV pandemic originated. It seems a combination of factors in Kinshasa in the early 20th Century created a 'perfect storm' for the emergence of HIV, leading to a generalised epidemic with unstoppable momentum that unrolled across sub-Saharan Africa."

The researchers' paper, published Thursday in the journal Science, also reports that the common ancestor of group M likely became infected some time around 1920, with 95 percent of the dates estimated by the research team falling between 1909 and 1930.

During those years, Kinshasa became one of the best-connected transportation hubs anywhere in central Africa. The researchers note that the initial spread of HIV closely followed transportation routes, especially railways.

"Alongside transport, social changes such as the changing behaviour of sex workers, and public health initiatives against other diseases that led to the unsafe use of needles may have contributed to turning HIV into a full-blown epidemic," Rodrigues Faria tells Newsweek.

The news of HIV's historical origins paint a picture of transmission that Rodrigues Faria hopes can help prevent epidemiologists stem the spread of infections in the future.

"Knowledge of the circumstances that facilitated the epidemic expansion can assist the development of effective education and prevention programs."