Called highly pathogenic avian influenza, the H5N1 bird flu virus making headlines in Michigan and across the U.S. got its name because it is so well adapted to infecting and killing birds. H5N1 has been circulating in the U.S. since January 2022 and globally since 2021.
What has scientists and researchers worried, however, is that the virus is increasingly spilling over to infect other animals, such as seals and racoons, bobcats, foxes, cows and alpacas — and now, even humans — and how little we know about how widespread the infections actually are.
Testing for H5N1 infections is voluntary. Farmers aren’t required to test their cows and people with symptoms aren’t required to be tested, either.
There have been only three known human cases of the virus in farmworkers in the U.S. this year — two in Michigan, and one in Texas.
All three had mild illness and fully recovered, but some scientists are concerned that the more the virus spreads, the greater chance it has to mutate to become better at infecting people — potentially making humans sicker and triggering an outbreak of a new, novel flu that could be reminiscent of the early days of the COVID-19 pandemic.