Officials in Minnesota, Iowa, and Wisconsin today reported a total of 14 more confirmed or probable H5N2 avian flu outbreaks on turkey and chicken farms, undermining hopes that warm spring weather would slow the virus's spread.
Minnesota reported eight outbreaks, including two in previously untouched counties and one on a farm housing more than 1 million chickens. Iowa, the nation's leader in egg production, revealed four probable outbreaks, three of them on turkey farms, while Wisconsin had two.
Agriculture officials have been saying that warmer weather with the advancing spring should slow the H5N2 virus, which does not survive as well in warm conditions. But so far the pathogen seems to be defying such expectations.
The two newly affected counties in Minnesota are Nicollet, which is about 50 miles southwest of the Twin Cities, and Renville, which is just northwest of Nicollet. The Nicollet outbreak involves a farm with 1,102,900 chickens, while the Renville farm holds 12,900 turkeys, the Minnesota Department of Public Safety (DPS) said in today's update.
The Minnesota Board of Animal Health (MBAH) specified that the Nicollet County farm houses egg-laying hens.
In addition, three more outbreaks were reported in the state's top turkey-raising county, Kandiyohi, raising its total to 29. Two of the farms harbor 89,200 and 11,200 turkeys. The release did not list a number for the third farm and said the barns there are being cleaned and disinfected because of exposure to potentially infected birds.
The state also reported Pipestone County's second outbreak, involving 72,900 turkeys, and the fourth and fifth events in Swift County, one farm having 72,200 turkeys and the flock size on the other one not yet determined. Pipestone is near the state's southwestern corner, while Swift is a west-central county that borders Kandiyohi.
The H5N2 toll in Minnesota has reached 80 farms in 21 counties, with about 5.34 million birds, not counting those on farms where flock sizes have not yet been reported, the DPS said. The state's annual turkey production is put at 46 million birds, making it the nation's leading producer.
Iowa outbreaks include big egg operation
The four new Iowa outbreaks include three turkey farms, but the one chicken farm is a big laying operation, with 2.8 million birds, the Iowa Department of Agriculture and Land Stewardship (IDALS) said in today's update. Birds at all four sites tested positive for an H5 virus, with the full subtype yet to be determined, officials said, but, as in previous cases, confirmation of H5N2 seemed likely.
The egg-farm outbreak in Wright County, in north-central Iowa, is the county's first. The three turkey outbreaks are the seventh and eighth outbreaks in Buena Vista County and the second outbreak in Cherokee County; both counties are in northwestern Iowa. Estimates of the number of birds at each site were still awaited.
The new events raise Iowa's outbreak count to 25. With the Wright County egg farm toll, the number of layer hens lost appears to be close to 19 million of the state's total population of about 60 million layers, in view of numbers reported last week.
Wisconsin outbreaks far apart
The two new Wisconsin outbreaks involve a Barron County farm with 14,600 breeding turkeys and a Jefferson County farm holding 127,970 chickens, the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATPC) announced today. The two counties are far apart, with Barron in the northwest and Jefferson in the southeast.
Barron County has had three previous H5N2 outbreaks, while Jefferson County had at least one, on a chicken farm in mid-April.
Today's update said the state has now had a total of 10 outbreaks involving about 1.6 million birds. Other affected counties are Juneau and Chippewa.
May 4 Minnesota DPS press release
MBAH avian flu page
May 4 IDALS statement
May 4 Wisconsin DATCP press release