Canada confirms first domestically acquired human avian flu case in B.C. teen

A British Columbia teenager is now in critical condition at B.C. Children's Hospital, fighting a strain of avian flu that had never before infected anyone acquired the virus domestically in Canada. The Public Health Agency of Canada confirmed the diagnosis this week after testing at the National Microbiology Laboratory in Winnipeg identified H5N1 in the patient's system—the same viral strain circulating through poultry flocks across the province in an outbreak that has persisted for years.

The teen, from the Fraser Health region, was hospitalized last Friday and tested presumptive positive for avian flu on Saturday. By Tuesday, when provincial health officer Dr. Bonnie Henry addressed the public, the patient's condition had deteriorated. The teenager is experiencing acute respiratory distress and remains in critical care. What makes this case particularly alarming is that the patient had no known exposure to farms or commercial poultry operations—no clear pathway to infection that epidemiologists can point to and say, here is where the virus jumped. The teen also had no underlying health conditions that might explain why the illness has progressed so severely.

Canada has seen avian flu in humans before, but only once, and under different circumstances. In 2014, an Alberta resident contracted H5N1 while travelling in China and later died from the infection. That case was imported, a consequence of international travel. This new case is different. It represents the first time the virus has moved from Canadian birds to a Canadian person through domestic transmission—a threshold the country's public health system has not crossed until now.

The H5N1 outbreak in B.C.'s poultry sector has been grinding on since the spring of 2022. In nearly three years, producers have culled approximately 6.4 million birds from domestic flocks in an effort to contain the spread. Most recent outbreaks have clustered in the Fraser Valley, the same region where this teenager lives. The virus has proven difficult to contain, cycling through farms despite biosecurity measures and culling operations.

Dr. Theresa Tam, Canada's Chief Public Health Officer, emphasized in a statement that officials are working across human and animal health agencies to investigate how the teenager became infected. She called on Canadians to remain vigilant as the country confronts the possibility that avian flu transmission to humans may not be a rare anomaly but an emerging risk. The source of this particular infection may never be identified—a troubling prospect that suggests the virus could be spreading through pathways public health has not yet mapped. For now, the teenager's fight for recovery continues in the hospital, while investigators search for answers in a landscape where the virus has already claimed millions of birds.