MINNEAPOLIS (AP) — A second Minnesota turkey farm has been struck by a form of bird flu that's deadly to poultry and will lose 66,000 birds, state and federal officials said Friday.
The U.S. Department of Agriculture said the virus hit a flock of 22,000 turkeys at a commercial farm in Lac qui Parle County of western Minnesota. It was the state's second confirmation of the highly pathogenic H5N2 avian influenza strain, which was confirmed at a Pope County turkey farm about three weeks ago.
That was the first detection of H5N2 in the Mississippi Flyway, a major bird migration route, and the same strain also has been confirmed in commercial and backyard flocks in Arkansas, Missouri and Kansas in the past three weeks. The same strain also has turned up in several western states in the Pacific Flyway.
State Veterinarian Bill Hartmann said there's no apparent connection between the two Minnesota farms, which he said are far apart and owned by different companies. While officials don't know how either operation became infected, he said they don't think it spread farm-to-farm.
State Health Commissioner Ed Ehlinger said no humans are known to have been infected with H5N2 in the U.S. While people who handle infected birds can be at risk, he said none who had contact with the Pope County turkeys became sick. Ten workers at the Lac qui Parle County farm will be monitored for the next 10 days.
"Our food system is safe, food is safe, and there's no public health risk," Ehlinger said.
But state Agriculture Commissioner Dave Frederickson said the new outbreak is another blow to poultry exports from Minnesota, the nation's top turkey producing state. More than 40 countries banned poultry imports from Minnesota after the first outbreak. Frederickson said Mexico had relaxed its controls in recent days but is now expected to fully re-impose them.
The new outbreak quickly killed all 22,000 of the 12-week-old turkeys in the affected barn, Hartman said. The 44,000 birds in the other two barns on the farm appear healthy but will be killed as a precaution and kept out of the food supply, he said.
Following standard protocols, the farm was quarantined and a surveillance zone was declared for a 10-kilometer radius around the farm. That zone extends into South Dakota, so Minnesota officials are working with their counterparts there on the response, Hartman said. He also said it's fortunate that there are no other commercial poultry operations within that zone, only backyard flocks.
Scientists consider wild migratory waterfowl to be a natural reservoir for avian influenza. While they don't generally get sick from flu viruses, they can spread them through their droppings. But there's disagreement over whether to blame them for the virus' arrival in Minnesota.
Lou Cornicelli, wildlife research manager for the state Department of Natural Resources, said that there was little open water near the Pope County farm and only a handful of resident wild ducks. He said his researchers took 148 environmental samples but found no H5N2.
"The direct waterfowl link in Minnesota doesn't add up," Cornicelli said.
But Hartman wasn't ready to discount waterfowl as the source.
"What we have agreed on is the source of this is unknown," he said.