This is a different strain of HPAI than the strains that caused the 2015 outbreak. There are no known cases of H7N8 infections in humans.

Samples from the turkey flock, which experienced increased mortality amounting to several hundred birds, were tested at the Indiana Animal Disease Diagnostic Laboratory at Purdue University, which is a part of USDA’s National Animal Health Laboratory Network, and confirmed by USDA on Friday.

State officials quarantined the affected premises and depopulation of birds on the premises has already begun. Depopulation prevents the spread of the disease. Birds from the flock will not enter the food system.

Following extra surveillance as a result of the case, officials found nine more outbreaks of H7 avian flu in flocks in southwestern Indiana.

On Sunday (17 January), APHIS confirmed the pathogenicity of the virus found on eight of the nine premises. The turkey flocks have been confirmed as low pathogenic avian influenza, with additional testing ongoing for the ninth flock.

“It appears that there was a low pathogenic virus circulating in the poultry population in this area, and that virus likely mutated into a highly pathogenic virus in one flock,” said Dr John Clifford, USDA Chief Veterinarian.

“Through cooperative industry, state and federal efforts, we were able to quickly identify and isolate the highly pathogenic case, and depopulate that flock.

"Together, we are also working to stop further spread of the LPAI virus, and will continue aggressive testing on additional premises within the expanded control area to ensure any additional cases of either HPAI or LPAI are identified and controlled quickly.”

“This finding of highly pathogenic H7N8 is unique to Indiana and the nation,” said Indiana State Veterinarian Bret D. Marsh, DVM.

“This strain is unrelated to those identified in the Upper Midwest in 2015, nor is it related to the HPAI case identified in a Northeastern Indiana backyard poultry flock that was affected last May.”

Indiana Governor Mike Pence stated: “Indiana is one of the largest poultry states in America, and I have directed all relevant agencies to bring the full resources of the state of Indiana to bear on containing and resolving the issue as quickly as possible... Hoosiers can be assured that we are taking all precautions to contain the situation and minimize the effects to Indiana’s robust poultry industry.”

Indiana’s poultry industry ranks fourth nationally in turkey production, first in duck production, third in eggs, and is a significant producer of broiler chickens. The poultry industry employs more than 14,000 Hoosiers and is valued at $2.5 billion.

APHIS said that the rapid testing and response was put in action as a result of months of planning following the previous avian flu outbreaks in 2015. The agency also reminded poultry keepers to maintain good biosecurity.