Surveillance of Highly Pathogenic Avian Influenza Virus in Wild Canids from Pennsylvania, USA

Authors

Kevin D. Niedringhaus, Cheyney University of PennsylvaniaFollow
Taylor C. Chan, University of PennsylvaniaFollow
Ashley McDowell, Maryland Department of AgricultureFollow
Lauren Mxwell, University of PennsylvaniaFollow
Madison Stevens, University of PennsylvaniaFollow
Lane Potts, University of PennsylvaniaFollow
Erica Miller, University of PennsylvaniaFollow
Eman Anis, University of PennsylvaniaFollow
Kyle Van Why, United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Harrisburg, PennsylvaniaFollow
Thomas Keller, Pennsylvania Game CommissionFollow
David Stallknecht, University of GeorgiaFollow
Rebecca L. Poulson, University of GeorgiaFollow
Kaitlyn Bahrs, Pennsylvania State UniversityFollow
Justin D. Brown, Pennsylvania State UniversityFollow

ORCID IDs

Niedringhaus https://orcid.org/0000-0002-9560-5621

Chan https://orcid.org/0009-0006-6117-9042

Miller https://orcid.org/0000-0002-1049-6228

Keller https://orcid.org/0009-0002-4666-8711

Poulson https://orcid.org/0000-0002-8087-3295

Brown https://orcid.org/0000-0002-9185-9288

Document Type

Article

Date of this Version

2024

Citation

MDPI Animals (2024) 14(24): 3700

doi: 10.3390/ani14243700

Academic Editors: Carla Cacciotto, Elisabetta Coradduzza, and Alberto Alberti

Comments

United States government work

Abstract

The avian influenza virus is a global pathogen with significant health and economic implications. While primarily a pathogen of wild and domestic birds, recent outbreaks of the H5N1 highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4b have caused mortality in a wide variety of mammals, including members of the Canidae family, on multiple continents. Despite sporadic mortality events globally, the epidemiology and pathobiology of H5N1 HPAIV in wild canids remains poorly defined. During 2022–2024, 41 wild canid carcasses (diagnostic cases), including 23 red foxes and 18 gray foxes, were tested for the influenza A virus (IAV) via PCR, with five red fox kits testing positive (12%). Infected animals had variably severe encephalitis, pneumonia, and occasionally myocarditis associated with strong immunolabeling for IAV. Serum from 269 wild canids in Pennsylvania was tested for antibodies to IAV, including 133 samples collected prior to 2021 (pre-H5N1 HPAIV 2.3.4.4b introduction) and 136 collected after 2022 (post-H5N1 HPAIV 2.3.4.4b introduction). All samples collected prior to 2021 were seronegative for IAV. Two coyotes from 2024 were seropositive for IAV but were negative for antibodies to the H5 and N1 subtypes. Collectively, these data suggest that while sporadic H5N1 HPAIV infection and mortality can occur in wild canids, particularly juvenile red foxes, infection was limited in these outwardly healthy and opportunistically sampled animals. Future studies should utilize a risk-based approach to target sampling of wild canids at increased risk for H5N1 HPAIV infection, such as those around waterfowl habitats or spatially around wild bird or domestic animal outbreaks.