- At least 41 bald eagles in 14 states have died after contracting H5N1, a strain of avian flu.
- Nearly 27 million chickens and turkeys were killed en masse to prevent spread of the virus.
- In chickens, the most deadly forms of avian flu have mortality rates upward of 90%.
A highly contagious bird flu strain that's ripped through the US in recent months is now spreading among the nation's national birds — bald eagles.
According to the latest data from the Department of Agriculture, at least 41 bald eagles in 14 states have died after contracting this particular strain, known as H5N1. "We are seeing significant mortality," Victoria Hall, executive director of the University of Minnesota's Raptor Center, told The Wall Street Journal. "The better data we can collect about what is happening in these populations, the better we can figure out how we can best support them."
Though bald eagles were once a dwindling bird population due to pesticides and hunters, they're no longer endangered. In fact, numbers have steadily risen since 2009, thanks to decades of conservation efforts.
Beyond bald eagles, the virus has been detected in flocks of wild birds, with more than 700 positive birds reported in 31 states, according to the Centers for Disease Control and Prevention.
Bald eagles are raptors — birds that hunt for living prey and scavenge for carcasses, which experts think is a possible route of transmission. "If the waterfowl are dying, then eagles can pick it up from eating those dead waterfowl," Krysten Schuler, co-director of the Cornell Wildlife Health Lab, told The New York Times.
Since January, the USDA has also detected the strain at several poultry farms, driving up the price of eggs and poultry in the process. Nearly 27 million chickens and turkeys were killed en masse as part of state containment efforts to prevent the avian flu's spread.
This new flavor of bird flu infection is dangerous for birds. Though symptoms from other strains can range from mild to severe, in chickens, the most deadly forms of bird flu have mortality rates upward of 90%, according to the CDC. More research is needed to understand how this novel strain differs from others, but experts say it's both severe and highly transmissible. The H5N1 strain, which can cause neurological and respiratory issues in birds, usually kills them within just two days.
Though flu can sometimes jump species and infect people, humans don't seem to be at increased risk of infection from this particular strain, according to the CDC. So far, there's been only one documented human case — a person in England who raised birds and was asymptomatic. No one in the US has been infected.
Experts at the Raptor Center recommend that people in states where the strain has been detected pause using bird feeders, to keep birds from congregating and spreading the virus.
"This is a virus to take seriously," Julianna Lenoch, a veterinary epidemiologist and national wildlife disease program coordinator for USDA, told Audubon. She added that government agencies like the Department of Agriculture will keep track of the flu in hopes of limiting its spread. "We just don't want to have any further introductions if we can help it."