Via The Globe and Mail: B.C. avian flu virus related to lethal strain in Asia. Excerpt:
The avian flu virus involved in an outbreak in British Columbia is related to a deadly strain that has spread through Asia and is now affecting North American poultry for the first time, the Canadian Food Inspection Agency says.
Experts say the presence of an avian flu virus with Asian lineage does not increase the danger to humans – which remains very low – but it could pose a significant risk to the poultry industry.
Nearly 250,000 chickens and turkeys are either dead or set to be euthanized due to avian flu, which has infected 11 sites in B.C.’s Fraser Valley since the beginning of the month.
Officials have already identified the subtype as a highly pathogenic, or high-path, strain of H5N2. Viruses with high pathogenicity kill birds, while their low-path counterparts typically do not.
The agency said tests have determined the virus contains genes both from H5N2, which is common to North American wild birds, as well as genes from a high-path Eurasian strain of H5N8. It keeps the label of H5N2 because its N gene is from H5N2.
“This is the first time a Eurasian lineage highly pathogenic H5 virus has caused an outbreak of avian influenza in poultry in North America,” it said in a statement.
“The appearance of this particular re-assortant virus is significant due to its ability to cause high mortality in domestic poultry.” The agency has yet to determine the source of the outbreak or how it is spreading. The statement noted it has not yet been detected in wild birds in Canada.
Earlier this week, the U.S. Department of Agriculture confirmed two wild birds in Washington state tested positive for avian flu – one with H5N2 and another with H5N8. It’s not clear whether those cases are connected to the B.C. outbreak.
Earl Brown, a University of Ottawa microbiologist who is an expert in the influenza virus, said a virus with Asian roots could be significant if it sustains itself in wild birds.