The New York Times reported on Saturday that a new version of bird flu has been showing up in mammals in the US more frequently this spring, raising concerns that the virus could eventually make the jump to humans.
According to the Times, in April a human society office in Wisconsin started getting calls about area fox kits, or young foxes, behaving strangely. As the office began collecting some of these kits for treatment, they noted a slew of strange symptoms that a battery of tests eventually revealed to be a result of infection with Eurasian H5N1 avian influenza, a highly virulent strain of the virus.
It was already known that this strain was spreading rapidly in wild birds in the US this spring, according to the Times report, which means an increased chance of the virus making its way to mammals that prey on those birds. At least seven US states have now detected the virus in red fox kits, and throughout North America the virus has been found in bobcats, a coyote pup, skunks, otters, a lynx, and a polecat. Two human cases have also been reported — on in the US and one in the UK — in people who had close contact with birds.
There is no evidence that mammals spread the virus — "This is very much still an avian virus," Richard Webby, an influenza expert at St. Jude Children's Research Hospital in Memphis told the Times — but it may be only a matter of time before that changes.
"What it's going to take for this virus to transition from being a duck or a chicken virus to being a mammalian virus is more chances to replicate in those mammalian hosts," Webby said. "So that's why when we see these mammals being infected by this virus, we do take notice."