INDIANAPOLIS – Ten premises in Dubois County, Indiana have been affected by H7N8 avian influenza, according to state and federal animal health agencies. The discovery of the virus has led to culls of 257,163 turkeys and 156,000 laying hens.

In response to the findings, the Indiana Board of Animal Health implemented a 10-km. control area primarily in Dubois County. Officials also extended a 10-km. “surveillance zone” by an additional 10 km. The surveillance zone includes parts of Crawford, Daviess, Martin and Orange counties. Sixty-two commercial poultry farms are in the control area and 52 farms are in the added surveillance zone. All infected sites are in Dubois County, BOAH reported.

BOAH noted that 114 commercial farms have tested negative for influenza since Jan. 19. A total of 182 state, federal and local responders are working in Dubois County on surveillance and response efforts.

State and federal surveillance teams have visited 1,248 residences in a 10-km. radius control zone around the original site to search for small, backyard flocks of birds for precautionary monitoring and testing. The teams found 46 backyard flocks and sampling is in progress.

A commercial turkey flock became the first case of HPAI reported in the US since this past June. On Jan. 17, the Animal and Plant Health Service of the US Dept. of Agriculture said eight turkey flocks were infected with low-pathogenic H7N8. APHIS said low-pathogenic H7 viruses have been known to mutate into HPAI viruses in the past. But Indiana State Veterinarian Bret D. Marsh, DVM said finding the cases as low-pathogenic strains shows animal health officials are keeping pace with the spread of the virus in Dubois County.

Dubois County leads Indiana's turkey production, growing 1.4 million birds annually. Indiana ranks fourth in the United States in turkey production, and is a major supplier of eggs, ducks and chickens. The state's poultry industry generates $2.4 billion and employs 14,000 individuals.