Low-risk H5N1 bird flu found in Pennsylvania ducks
Mallard ducks in Pennsylvania have tested positive for a low-pathogenic strain of the H5N1 bird flu virus, the U.S. Agriculture and Interior departments said on Saturday, adding to cases detected recently in Maryland and Michigan.
A strain of the H5N1 avian influenza virus was found in wild ducks sampled August 28 in Crawford County in northwestern Pennsylvania.
“Testing has ruled out the possibility of this being the highly pathogenic H5N1 strain that has spread through birds in Asia, Europe and Africa,” USDA and Interior said in a statement. “Test results thus far indicate this is low pathogenic avian influenza, which poses no risk to human health.”
The government said it was conducting additional tests to determine, in part, if the ducks had H5N1 or two separate strains with one virus contributing H5 and the other N1. A second round of tests could take five to 10 more days to confirm whether it was the low-pathogenic H5N1 bird flu.
The virus also has been found during the last month in Michigan and on Friday in Maryland. The Maryland mallards did not appear sick so the samples, collected on August 2 as part of a research project, were not given high priority when sent to USDA labs for testing.
The U.S. departments of Agriculture and Interior are working with states to collect between 75,000 and 100,000 wild bird samples in addition to more than 50,000 environmental tests throughout the United States.
A low-pathogenic strain, which produces less disease and mortality in birds than does a high-pathogenic version, poses no threat to humans. It is common for mild and low pathogenic strains of bird flu to appear in the United States and other countries.