OAHN Wildlife Project: Enhanced Avian Influenza Surveillance in Wild Mammals 2023-2024

Project Lead: Drs. Claire Jardine and Alex Reid

Collaborators: Brian Stevens, Larissa Nituch

Project Summary

Wild birds are the primary focus of current avian influenza surveillance efforts.  However, detections of avian influenza virus (AIV) in wild mammals have raised concerns about mammalian adaptations and highlighted the need for enhanced AIV surveillance in wild mammals.

Our objective for this project was to enhance surveillance for avian influenza in wild mammals in Ontario, with a focus on high-risk periods associated with wild bird migration (i.e., fall 2023, and spring and fall 2024).  We tested samples from 251 dead wild mammals submitted to the CWHC between October 15, 2023, and December 31, 2024 for AIV at the Animal Health Laboratory.  One skunk, received in March 2024, and 1 mink, received in December 2023, tested positive on both the matrix and H5 PCR at the AHL. These samples were both sent to the CFIA for additional testing and characterization. The mink sample was not confirmed positive at the CFIA, but the skunk sample was confirmed positive for the H5N1 subtype (2.3.4.4b) AIV based on PCR.