Just over a year after the first confirmed bird flu cases in Minnesota, a backyard flock in Le Sueur County has been depopulated after a federal laboratory confirmed an outbreak of highly pathogenic avian influenza.

A mixed flock of 114 chickens, ducks and geese was infected with the virus, said the Minnesota Board of Animal Health, following testing by the U.S. Department of Agriculture's National Veterinary Services Laboratories in Ames, Iowa.

The positive case comes four months after a flock in Minnesota was last confirmed with the variant. The return of devastating flu — which is believed to be spread by migratory birds and necessitates the culling of a flock due to prevent further disease spread — was expected.

"We were fortunate to get a reprieve from the virus during the past few months," said Dr. Shauna Voss, senior poultry veterinarian at Minnesota's Board of Animal Health. "We've been anticipating the return of the virus and are recalling our partner resources back to the fight."

State officials have not released the exact location of the infected flock or the species of domesticated birds. But a statewide map on Tuesday morning showed a quarantine zone in western Le Sueur County near the Minnesota River, covering parts of Blue Earth and Sibley counties.

Commercial turkey operations in Pennsylvania, Illinois and Iowa have also reported infections this year. As higher temperatures settle into the Upper Midwest, wild birds — known drivers of transmission — also fly northward.

The H5N1 virus does not threaten food safety and is a low risk for humans with just one U.S. case reported in a poultry worker in Colorado last year. That person has since recovered. But the outbreak has disrupted poultry farms and devastated wildlife. The price of eggs remains high after hard-hit states like Iowa lost millions of chickens to the outbreak.

"There's no way to anticipate or estimate the impact of HPAI in Minnesota for 2023," said Ashley Kohls, executive director of Minnesota Turkey Grower Association. We can only prepare for the disease, and use the tools and resources available to mitigate the impact — which turkey growers are actively doing."

Two weeks ago on the steps of the State Capitol in St. Paul, Rep. John Burkel, R-Badger, told a crowd gathered for a National Ag Day proclamation read by Gov. Tim Walz that any celebratory mood was tempered against rumblings of a possible confirmation in a Murray County flock.

On Monday, a spokesman for the Board of Animal Health said a federal lab determined that the Murray County case involved a H1N2 swine lineage virus, not the subtype found in the current case.

Burkel, a turkey grower from northwestern Minnesota, said on Tuesday that he expected a positive case at least a month ago.

"Sadly, practice makes perfect," Burkel said, regarding the commercial poultry industry's biosecurity readiness. "You're going to see the vigilance from the industry show itself again."

The confirmation in Le Sueur County marks the 111th flock infected in Minnesota. Last year, more than 4 million birds, mostly turkeys, were killed in Minnesota to prevent the spread of the disease.

Last year's bird flu outbreak was the largest in U.S. history, claiming 58 million birds in commercial and backyard flocks.

Minnesota is the nation's leading producer of turkeys and last year's outbreak of bird flu also had a lasting impact on Willmar, Minn.-based Jennie-O, owned by Hormel Foods.

"[There] is absolutely not enough turkey coming through to support the business," Hormel CEO Jim Snee told analysts this month. However, the company is not expecting a repeat of the scale of last year's outbreaks.

"The turkey business is still in a very favorable position," Snee said. "Turkey demand is strong."

Scores of wild birds were also killed by the virus last year; in Minnesota, great horned owls, bald eagles and red-tailed hawks were especially affected and could be at risk again this year. Cases of H5N1 have also been confirmed in red foxes in Minnesota and a striped skunk.

The resources to combat the virus encompass a web of state, federal and local authorities and surveillance by producers. Last week, Animal Health announced the group's executive director and State Veterinarian Dr. Marion Garcia — who'd been on the job for less than a year — would no longer lead the state agency following a performance review.

The agency has begun a search for a new state veterinarian.