The Canadian Food Inspection Agency has identified a highly infectious form of avian influenza in multiple samples collected in southern Manitoba following an unusual bird die-off. Approximately 500 bird carcasses, predominantly Canada geese, were discovered near water streams in southern Manitoba in early December. While separate groups of deceased birds were located near the Red River north of Winnipeg’s Perimeter Highway, a notable concentration was found in a collection of ponds in Niverville.
Biologist Frank Baldwin from the Canadian Wildlife Service informed CBC News that bird samples were sent to the Canadian Food Inspection Agency after testing positive for avian influenza, also known as bird flu, to determine the specific strain. The federal agency reported submitting 39 wild bird samples for testing on December 11, with laboratory results confirming 38 samples were positive for the highly pathogenic H5N1 strain of avian influenza.
Hannah Wallace, a researcher at the University of Manitoba specializing in viral immunology, expressed relief that the samples tested positive for the H5N1 strain, known to cause significant disease and mortality in birds. Wallace had concerns that the virus might have mutated into a more dangerous strain for both birds and humans, as high mortality rates in geese with avian influenza were previously unseen.
The detected H5N1 strain is prevalent among domestic poultry and wild bird populations in North America, according to the food inspection agency. Wallace emphasized that the identification of H5N1 was not unexpected, as most Canadian birds have existing immunity due to prior exposure. Factors such as weakened or underfed birds being more vulnerable to H5N1 were considered, with speculation that the deceased birds in southern Manitoba might have overstayed in the province due to mild fall conditions, leading to food scarcity amid cooler weather.
Research indicates that avian influenza can persist in the environment even after bird migration, potentially surviving in ponds or river sediment until spring. The behavior of avian influenza varies annually, with some bird populations developing high antibody levels for defense. However, the duration of this protection remains uncertain, raising concerns about potential mortality among migrating snow geese and Ross’s geese in Canada in the coming months.
Avian influenza has been a longstanding concern for scientists and poultry farmers in Manitoba due to its contagious and lethal nature. While farmers implement enhanced biosecurity measures to prevent transmission, the challenges of controlling bird flu from wild birds persist, particularly during fall and spring migrations. Candace Lylyk, owner of Breezy Birds Farm in Morris, Manitoba, highlighted the efforts taken to safeguard her poultry farm from wild birds, emphasizing the importance of maintaining strict protocols to protect her livelihood and birds, which she views as family.