IFL Science A dead squirrel, an outbreak in monkeys, and the trail of a virus. or the first time, researchers have captured direct evidence of the monkeypox virus (MPXV) jumping between two wild animal species. Detecting interspecies transmission in the wild is notoriously difficult, but this remarkable piece of scientific detective work offers insight into how viruses circulate in ecosystems and how they may ultimately spill over into humans. The story starts in 2023 when scientists at the Taï Chimpanzee Project in Côte d’Ivoire found a troop of sooty mangabeys (Cercocebus atys) that had been struck with Mpox. The virus spread aggressively: four infants died, and at least a third of the group developed the telltale rashes and lesions associated with infection.
The researchers managed to get their hands on faecal samples of the infected monkeys, confirming the presence of MPXV. Intriguingly, it showed the group was infected with a strain very similar to one that was identified in a fire-footed rope squirrel (Funisciurus pyrropus) found dead nearby just a few months prior.
Then came the smoking gun. One sample collected eight weeks before the outbreak contained DNA from both the virus and a fire-footed rope squirrel. Since sooty mangabeys from this group had already been seen eating the squirrels, the possible chain of events seems very clear.