Researchers have tracked the origin of HIV
Researchers have confirmed for the first time that the HIV pandemic originated in the Congo in the 1920s.
Though the earliest recorded case of HIV in a human was in the Congo in 1959, researchers have previously only been able to speculate about when the disease made the jump from primates to humans.
However, researchers at the University of Oxford and and the University of Leuven have now been able to find its source with “a high degree of certainty” – with its ‘family tree’ leading to Kinshasa in the 1920s.
Zoologist Oliver Pybus told Reuters: “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.”
HIV has had many different strains that have transitioned to humans – but only one strain is responsible for the global crisis.
Professor Pybus added: “You can see the footprints of history in today’s genomes, it has left a record, a mutation mark in the HIV genome that can’t be eradicated.
“Why did most of [the HIV strains] die out, and why did some of them — like HIV-2 – go on to generate local epidemics in Africa, and why did only one go to become a global pandemic?
“To answer that, we needed to try to reconstruct the spread through space and time of the global pandemic strain.”
He concluded that living conditions in the city allowed HIV to spread, adding: “It was a very large and very rapidly growing area and colonial medical records show there was a high incidence of various sexually transmitted diseases.
“There are two aspects of infrastructure that could have helped.
“Public health campaigns to treat people for various infectious diseases with injections seem a plausible route [for spreading the virus].
“The second really interesting aspect is the transport networks that enabled people to move round a huge country.”
Oxford Zoology lecturer Nuno Faria added: “We think it is likely that the social changes around the independence in 1960 saw the virus break out from small groups of infected people to infect the wider population and eventually the world.”