,Treatment groups of ducks were exposed to different virus doses (2, 4, 6 log10 50% egg infectious doses) and by different routes (contact or intrachoanal). The experimental setting was a laboratory with animal care as approved by the institutional animal care and use committee as appropriate for the species and age of bird. Data are the virus titers shed by the oral and cloacal route for individual mallard ducks exposed to H5N1 highly pathogenic avian influenza virus by day post exposure. Samples were collected through 11 days post exposure. Virus titer equivalents were determined by quantitative real-time RT-PCR. Serological data are serum antibody titers to the challenge virus as determined by hemagglutination inhibition assay (reciprocal of the log2 dilution) determined with serum collected 10 or 11 days post exposure.,,

This dataset includes epidemiology, clinical signs, gross and microscopic pathology, and virology data from two red foxes (Vulpes vulpes) and one fisher (Pekania pennanti) submitted to the USGS-National Wildlife Health Center for cause-of-death determination and confirmed positive for highly pathogenic avian influenza (HPAI) H5N1 by USDA’s National Veterinary Services Laboratories. The foxes were juveniles from North Dakota and the fisher was an adult from Wisconsin. Clinical signs included neurological deficits such as ataxia, lethargy, or paralysis. Gross and microscopic lesions included myocardial pallor, pulmonary and hepatic congestion, meningoencephalitis, interstitial pneumonia, myocardial necrosis, and hepatic necrosis. Highly pathogenic avian influenza H5N1 2.3.4.4 was detected in swabs and/or organ tissues by PCR; genotype B3.1 was identified in the foxes and B3.2 was identified in the fisher. Death of all three animals was attributed to HPAI.

This dataset includes epidemiology, clinical signs, gross and microscopic pathology, and virology data from two red foxes (Vulpes vulpes) and one fisher (Pekania pennanti) submitted to the USGS-National Wildlife Health Center for cause-of-death determination and confirmed positive for highly pathogenic avian influenza (HPAI) H5N1 by USDA’s National Veterinary Services Laboratories. The foxes were juveniles from North Dakota and the fisher was an adult from Wisconsin. Clinical signs included neurological deficits such as ataxia, lethargy, or paralysis. Gross and microscopic lesions included myocardial pallor, pulmonary and hepatic congestion, meningoencephalitis, interstitial pneumonia, myocardial necrosis, and hepatic necrosis. Highly pathogenic avian influenza H5N1 2.3.4.4 was detected in swabs and/or organ tissues by PCR; genotype B3.1 was identified in the foxes and B3.2 was identified in the fisher. Death of all three animals was attributed to HPAI.

This data release details the results of avian influenza sampling of dabbling ducks in Maine and Maryland. These data support an associated USGS publication.

Clade 2.3.4.4b Eurasian-origin H5N1 entered North America in late 2021 and spread across the continent. While studies have characterized the antibody response mounted by dabbling ducks following exposure, little data is available for diving ducks. This study sought to identify influenza A virus (IAV) infection and antibodies in Lesser and Greater Scaup captured in Maryland, Illinois, and Rhode Island. In Maryland, IAV seroprevalence increased from the 2021/2022 to 2022/2023 sampling season, with IAV antibody prevalence increasing for juvenile (38% to 80%) and adult (82% to 90%) Lesser Scaup. While adult Lesser Scaup sampled in Illinois in 2021/2022 had IAV antibody prevalence comparable to those sampled in Maryland (76% and 82%, respectively), they had higher antibody prevalence to both H5 (48% and 18%) and N1 (68% and 35%), potentially due to being sampled in March versus December and January. Greater Scaup captured in Rhode Island had comparable IAV, H5, and N1 antibody seroprevalence to Lesser Scaup in Maryland during the same season. Our data suggest that Lesser Scaup had limited antibodies to highly pathogenic H5 IAV prior to the introduction of clade 2.3.4.4b H5N1 to North America, but relevant antibodies were widely observed in the months and year following.

These data describe the results of virus isolation from oropharyngeal/cloacal swabs and testing of sera by a commercial blocking enzyme-linked immunosorbent assay (bELISA) and hemagglutinin (HA) specific testing by microneutralization (MN) and hemagglutination inhibition (HI) for Lesser Scaup in both the Atlantic and Pacific Flyways and Greater Scaup in the Pacific Flyway. These data support a USGS published manuscript.

This data release provides the predicted proportion of influenza-positive birds testing positive for H5 and H7 subtypes of IAV for each species at monthly intervals for each county centroid in the continental United States. This data supports a paired USGS publication.

These data describe avian influenza sampling efforts for eastern wild turkeys (Meleagris gallopavo silvestris) across the Maryland portion of the Delmarva Peninsula, USA in the winter of 2023-2024

These data describe avian influenza sampling efforts for eastern wild turkeys (Meleagris gallopavo silvestris) across the Maryland portion of the Delmarva Peninsula, USA in the winter of 2023-2024

Dataset containing avian influenza screening results for waterfowl and gulls sampled during autumn in (or near) Izembek National Wildlife Refuge (NWR), Alaska, 2011-2024. These data contain information on species, age, and sex of birds sampled, collection dates, and laboratory testing information used to determine the presence and absence of influenza A viruses (IAVs).