Gorilla HIV makes leap to humans

日期:2019-03-08 07:04:21 作者:佟赙 阅读:

By Ewen Callaway A new strain of HIV has jumped from gorillas to humans. So far, only one person, a 62-year-old French woman from Cameroon, has been found to be infected with the virus, which closely resembles strains of simian immunodeficiency virus (SIV) recently discovered in western gorillas in the wild. “It would be surprising if there aren’t some more” human cases, says David Robertson, a bioinformaticist at the University of Manchester, UK who analysed the virus’s DNA along with colleagues in France. “We don’t think this is a direct gorilla-to-human transmission.” Until 2004, the infected woman lived in a suburb of Cameroon’s capital city Yaoundé, where she didn’t come into contact with apes or eat their meat – SIV’s primary route to humans. This means that she probably acquired the infection from another human, likely through sexual contact. The woman hasn’t yet shown any sign of a compromised immune system – the hallmark of AIDS – but tests on laboratory-cultured human cells suggest that the virus can replicate in the same white blood cells as other strains of HIV. However, the new virus should be susceptible to anti-retroviral drugs that slow the growth of other strains of HIV, Robertson says. Based on its genetic sequence, the virus appears most closely related to a number of SIV strains collected recently in gorilla faecal samples from forests in Cameroon. These viruses also resemble “group O” strains of HIV, which infect far fewer people than other strains of HIV, most of them in Cameroon. The discovery of a gorilla virus in humans could suggest that some of these group O viruses came from gorillas, Robertson says, but it’s also possible that the virus originated chimpanzees and was transmitted independently to gorillas and to humans. “Until we do more sampling we’re also guessing a little bit,” Robertson concedes. Moreover, the virus’s discovery adds to growing evidence that new HIV strains may regularly emerge from other primates, says Martine Peeters, a virologist at the University of Montpellier, who led the team that identified the first gorilla SIV strains. “It is just an additional demonstration that these viruses have jumped several times from apes to humans.” Virologists could be missing many of these transmissions because existing HIV tests are biased to identify already circulating strains of the virus. “We’re very good at detecting HIV, so unless you do these other more in depth tests, you wouldn’t necessarily detect these very divergent viruses,” Robertson says. Journal reference: Nature Medicine (DOI: 10.1038/nm.2016) More on these topics: