The USDA and Department of the Interior announced Thursday that samples collected from wild Northern pintail ducks in Ohio contain no avian influenza. Preliminary screening had suggested the presence of H5 and N1 subtypes in the samples, but further testing shows that the samples do not contain the virus.
Initial rapid screening tests of samples are prone to be oversensitive and detect inactive viruses. In this case, the initial tests showed a weak positive for H5 and N1 subtypes in the samples, but the standard confirmatory tests and isolation test overturned the initial results.
No highly pathogenic avian influenza has been found in North America, but USDA and DOI have announced 12 cases of low pathogenic avian flu in six states. Low pathogenic avian flu poses no threat to human health and is commonly found in wild North American birds. Officials continue to test for avian influenza across the country to watch for the dangerous highly pathogenic avian flu.