MITCHELL, S.D. (MITCHELLNOW) Genetic testing indicates the H5N1 bird flu virus jumped from wild birds to dairy cattle in Texas approximately four months before it was identified in late March, according to agricultural researchers from the United States Department of Agriculture, Iowa State University, Cornell, Texas A & M and Washington State University. To date, bird flu has been confirmed in 36 dairy herds, from Idaho to North Carolina, including here in South Dakota. The interstate shipment of asymptomatic, untested cattle has contributed to the spread of the H5N1 virus, colloquially known as bird flu.
The team of researchers said testing was essential to make sure the virus does not adapt to increase its transmissibility. There have been as many as five cattle-to-poultry, one cattle-to-raccoon, two cattle-to-domestic cats, and three cattle-to-wild bird transmission events on dairy farms with cattle infected with the virus.
Meanwhile, the USDA said it had found no bird flu virus in 30 samples of ground beef purchased in states with infected herds. The FDA says its tests show that pasteurization kills the H5N1 virus and that the milk supply is safe. The CDC says the risk to human health from the virus is low.