Avian Influenza Surveillance Targeting Iowa’s Resident and Migratory Shorebirds

In August 2022, the Iowa Department of Natural Resources with partners at Iowa State University started sampling resident and migratory shorebird species using molecular diagnostics and serology. Killdeer (Charadrius vociferus) became a primary target of this project as habitat generalists, given the wide availability of breeding pairs across the state and local abundance at commercial poultry operations. We also focused on sampling diverse shorebird species during fall migration following recruitment, as opposed to spring migration when most shorebird surveillance in North America has occurred. To date, we have deployed a range of different capture methodologies, including walk-in traps, spot lights, and environmental sampling on killdeer (n=80), as well as mist nets on 11 species of live shorebird (n=159). We also sampled killdeer dispatched at poultry facilities by USDA Wildlife Services (n=165). To date, only one juvenile pectoral sandpiper (Calidris melanotos) has tested positive for H4N6 low pathogenic avian influenza (LPAI) on pooled oropharyngeal and cloacal swabs, which to our knowledge is the first detection reported in this species. Moreover, as one of only 46 pectoral sandpipers sampled in 2023, this may hint at an apparent prevalence as high as 2% in this species, which warrants further investigation.

Rachel M. Ruden (1,2), Stephen J. Dinsmore (3), Valerie Kim (2), Maria V.C. Peixoto (2), Amro Hashish (2), Eman A. Gadu (2), Yuko Sato (2), and Mohamed El-Gazzar (2) (1) Wildlife Bureau, Iowa Department of Natural Resources (2) Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University (3) Department of Natural Resource Ecology and Management, Iowa State University

Notable outbreaks, field and molecular epidemiology, and surveillance in wild birds