After a quiet summer, bird flu cases are rising again. Scientists expected the development, but what happens next is still uncertain. After a summer lull in U.S. cases of avian influenza in both poultry and dairy cattle—and no human infections reported in the country since February—the virus is back.
Bird flu’s return threatens major economic losses for the U.S. agricultural system and raises a small but real risk of a human pandemic. Scientists expected bird flu to return. It was highly unlikely that, following three full years of infecting U.S. poultry and making the surprising leap into cows, the virus would simply disappear.
The currently circulating bird flu subtype H5N1 is here to stay. “We’ve resigned to this phase,” says Seema Lakdawala, a virologist at Emory University. “Now we have to figure out what we’re doing next.”
Scientific American spoke with Lakdawala and other experts about why the virus has returned, what threats it poses, and what people need to know.
How prevalent is bird flu right now?
In poultry, bird flu is on the rise: according to the U.S. Department of Agriculture, 50 flocks of commercial and backyard poultry in the country had confirmed avian influenza infections in October. Farmers cull all birds on infected premises to reduce the virus’s spread, and this month, more than three million animals have been killed to date.