The Canadian Food Inspection Agency has identified a highly infectious form of avian influenza in numerous samples gathered in southern Manitoba following an unusual mass bird mortality event. Approximately 500 bird carcasses, predominantly Canada geese, were discovered near waterways in southern Manitoba in early December. While separate groupings of deceased birds were located near the Red River north of Winnipeg’s Perimeter Highway, the largest concentration was observed in a set of ponds in Niverville.
Frank Baldwin, a biologist with the Canadian Wildlife Service, informed CBC News that bird samples were forwarded to the Canadian Food Inspection Agency after testing positive for avian influenza, commonly known as bird flu, to determine the strain of the infection. The federal agency reported submitting 39 wild bird samples for testing on December 11, with lab results confirming that 38 samples were positive for the highly pathogenic H5N1 strain of avian influenza.
Hannah Wallace, a viral immunology expert from the University of Manitoba, noted that while H5N1 can cause significant disease and mortality in birds, she was relieved that the samples tested positive for the known strain. She expressed concern that a potential mutation of the virus into a more hazardous form, affecting both birds and humans, had not been observed before.
The detected H5N1 strain in the collected samples is prevalent among domestic poultry and wild bird populations in North America, according to the food inspection agency. Wallace mentioned that since most Canadian birds have been previously exposed to H5N1, they might possess some level of existing immunity, although weaker or undernourished birds could be more susceptible to contracting the virus.
Avian influenza can persist in the environment even after birds have migrated for the season, Wallace emphasized. While she believed the virus might not remain in the water where the deceased birds were found, it could potentially survive in ponds or river sediment until spring despite cold temperatures. Baldwin of the Canadian Wildlife Service mentioned the varying behavior of avian influenza each year, indicating a likelihood of mortality among snow geese and Ross’s geese during their migration through Canada in April and May.
Poultry farmers in Manitoba have long been concerned about avian influenza due to its high contagion and fatality rates. Rod Wiebe, the board chair of Manitoba Chicken Producers, highlighted the challenge of controlling the virus when transmitted by wild birds, especially during peak periods like fall and spring migrations. Candace Lylyk, owner of Breezy Birds Farm in Morris, shared her efforts to safeguard her poultry farm against wild birds carrying the virus, implementing strict bio-security measures and operational changes to prevent potential outbreaks.
The discovery of H5N1 avian influenza in the deceased Manitoba birds has raised awareness among scientists and farmers, emphasizing the need for continued vigilance and preventive measures to mitigate the risks associated with the virus.