WASHINGTON — The U.S. Department of Agriculture on Jan. 15 confirmed the presence of highly pathogenic H7N8 avian influenza (HPAI) in a commercial turkey flock in Dubois county in Indiana. This strain of bird flu is different from the strains in the HPAI outbreak that affected turkeys and chickens last year, according to the U.S.D.A. That outbreak led to the depopulation, including euthanizing birds, of 7.5 million turkeys and 42.1 million egg-layer and pullet chickens in the United States, the U.S.D.A. reported on Sept. 18, 2015.
The U.S.D.A. on Jan. 17 of this year said it is working with the Indiana State Board of Animal Health and the affected poultry industry. Depopulation of the turkeys in the affected flock had begun, and it should prevent the spread of the diseases and keep birds from the flock from entering the food system.
The U.S.D.A.’s Animal and Plant Health Inspection Service (APHIS) on Jan. 16 said it had confirmed the presence of H7N8 avian influenza in nine other flocks in southwestern Indiana. They were identified as part of surveillance testing in the control area surrounding the initial case. On Jan. 17 APHIS said it had confirmed eight of nine additional detections were low pathogenic avian influenza (LPAI). The ninth flock was being tested. Low pathogenic avian influenza has mutated into highly pathogenic avian influenza in the past.
“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 John Clifford, D.V.M., chief veterinarian for the U.S.D.A. “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.”There are no known cases of H7N8 avian influenza infections in humans, according to the U.S.D.A.