State health officials say a strain of bird flu that’s deadly to poultry has been discovered in Minnesota, after the population of a commercial turkey barn was decimated in a matter of days — from a flock of 15,000 to fewer than 100.
Health officials said Thursday that the risk to the general public from the virus — known as H5N2 avian influenza — was “very low,” though there was some occupational risk to workers handling the turkey flock in west-central Minnesota.
The four workers who worked at the Pope County farm — which was not identified — were being monitored. However, no human infections from this strain of bird flu have been detected anywhere.
Health officials said there were four barns on the property — two for raising turkeys and two for laying eggs — and only one of the poultry raising barns experienced the severe “death loss.”
Officials quarantined the farm and said the remaining turkeys would be killed to prevent the disease’s spread. No birds ever went outside the barns.
Still, state and federal officials plan to scour the area around the farm for the presence of infected birds, though the likelihood of finding any is considered slim because of the frigid conditions.
“We’re optimistic (about possibly containing an outbreak) because there are no other commercial operations in that area,” said state Agriculture Commissioner Dave Frederickson. “If we can get through the next 21 days (the disease’s incubation period) without finding anything, we should be in good shape.”
The disease originates from wild waterfowl — geese, ducks and shorebirds — and is endemic in that population. Infected flocks that originated in Eurasia eventually traveled to North America in late 2014 via migratory pathways, including the Pacific Flyway. Once there, the Asian strains mixed with North American avian influenza viruses, creating the new strain. The strain has been confirmed in backyard and wild birds in Washington, Oregon and Idaho.
Thursday’s announcement marks the first time the strain has been detected in the Mississippi Flyway.
Waterfowl typically do not experience severe symptoms and often don’t appear sick. Poultry, on the other hand — including chickens, turkeys and pheasants — are particularly susceptible to the disease.
“Songbirds, the types of birds that come to your backyard feeders, really don’t get infected as a general rule,” said Dr. Carol Cardona, professor of avian health at the University of Minnesota’s College of Veterinary Medicine. “We don’t know why. … Those smaller birds are not great hosts of the virus.”
Cardona noted that infected poultry would not make it to food markets, as it is all tested for influenza.
The disease is typically spread through fecal matter, which can be tracked into commercial farms by workers.
According to the Minnesota Turkey Growers Association, Minnesota is the top producer and processor of turkeys in the country, raising 46 million birds annually, worth around $750 million.
State officials said they suspect the outbreak could have an impact on the state’s poultry export business, which totaled some $92 million in 2013.
That amount represents 10 to 12 percent of the total value of state turkey production, said Steve Olson, executive director of the Minnesota Turkey Growers Association.
“Our biggest area of growth has been export markets,” Olson said. “We were watching for this, but we didn’t expect to see it this soon.”
Frederickson acknowledged that exports could take a hit, as has been the case in the Pacific Northwest.
“We’re very cognizant of that,” Frederickson said. “We can only prepare for the worst and hope for the best.”
The Pope County farm’s owners noticed elevated mortality in their flock on Feb. 26, when they lost an initial 70 birds. The following day, they lost hundreds and contacted state officials. A U.S. Department of Agriculture lab confirmed the virus to state officials Wednesday night.
Those coming into contact with sick or dead poultry or wildlife should wash their hands with soap and water and change clothing before coming into contact with healthy domestic poultry and birds.