In this Nov. 16, 2009 file photo, chickens stand in their cages at a farm near Stuart, Iowa. Canada's Public Health Agency has confirmed that a British Columbia teenager hospitalized last Friday is the country's first ever human case of domestically acquired H5N1 avian flu. (AP Photo/Charlie Neibergall, File)

Canada's Public Health Agency has confirmed that a British Columbia teenager hospitalized last Friday is the country's first ever human case of domestically acquired avian flu.

The agency said in a statement Wednesday that testing at Canada's National Microbiology Laboratory in Winnipeg confirms the teen did contract the H5N1 avian flu, the same strain related to viruses found in B.C. flocks in an ongoing outbreak at poultry farms.

The teenage patient was said to be in critical condition on Tuesday after being admitted days before to B.C. Children's Hospital, and a spokesman from the office of B.C.'s provincial health officer said Wednesday that they are not aware of any change to that status.

"Our heart goes out to the teenager who is sick," Dr. Theresa Tam, Canada's chief public health officer, said in an interview with The Canadian Press.

"It's just a reminder that H5N1 can cause a range of illnesses all the way from asymptomatic to severe outcomes, and that we need to take this virus seriously, even if it's a sort of zoonotic transmission from animal to human because it can cause a severe outcome in the individual who's infected," Tam said.

The public health agency said it was notified by B.C. health authorities on Saturday that the teenager tested presumptive positive for the avian flu, and Tam said field epidemiologists are looking at potential sources for the teen's exposure.

The investigation "could take some time," she said, because they haven't been able to directly ask the teenager about where they might have become infected.

"We are unable to speak to the patient because the patient is quite sick," Tam said. "And so, I think some of the information is necessarily second-hand from the family members.

"The good news is up to now, none of the close contacts like family members have tested positive.”

A statement from the agency added that Canadians "must remain vigilant" in the fight to prevent the spread of avian flu between animals and humans.

B.C. Provincial Health Officer Dr. Bonnie Henry said at the news conference Tuesday that the teen, who is from the Fraser Health region, was "experiencing acute respiratory distress" while at B.C. Children's Hospital.

The teen did not have any pre-existing conditions that would explain the severity of the illness, and Henry said the patient did not live on a farm or have contact with commercial poultry flocks. The source of the infection may never be found, she said.

There was one previous case of avian flu in humans in Canada in 2014 in Alberta. The infected person eventually died. Health officials determined in that case that the victim likely contracted the virus while travelling in China.

B.C.'s commercial poultry sector has been damaged by avian flu outbreaks in recent years, with about 6.4 million birds in domestic flocks having been culled since the spring of 2022.

Most of the outbreaks reported in the last few months in B.C. have been in the Fraser Valley, located within the Fraser Health region.

This report by The Canadian Press was first published Nov. 13, 2024.

News from © The Canadian Press, 2024