USDA officials announced today that fecal samples gathered from wild birds in Maryland are undergoing confirmatory tests to verify an infection of low-pathogenicity H5N1 avian flu. The samples, gathered Aug. 2, from resident wild ducks in Queen Anne's County, Maryland, as part of an Ohio State University research project, were from birds showing no sign of infection. Lack of infection is a sign of low pathogenicity avian influenza.
Due to the low-path early conclusion the samples were not prioritized for testing; however on Aug. 24, the National Veterinary Services Laboratory received the samples and on Thursday noted that nine samples were positive for the H5N1 subtype. On Friday, a genetic analysis showed that the virus is similar to low-path strains found previously in North America.
Additional testing will confirm the pathogenicity of the virus and those results are expected in the next two weeks. They will be made public when completed. Discovery of low-path viruses in wild birds is not uncommon.