Is the avian influenza virus circulating in Canada?

TORONTO — We've been hearing a lot about H5N1, or highly pathogenic avian influenza, since a British British teenager became the first Canadian to be hospitalized with the virus.

It's still unclear how the teenager was infected, but Canada's chief public health officer, Dr. Theresa Tam, said Wednesday that genome sequencing has shown that the strain is similar to a strain that originated on a poultry farm in British Columbia. He said the results showed that he had the H5N1 strain.

More than 20 poultry outbreaks have been confirmed across the province since early October, according to a recent news release on the B.C. government's website.

Tam said in an interview that the boy's H5N1 strain is not the same genotype found in people who infected dairy cows in the United States.

Although there have been several outbreaks of avian influenza on dairy farms in multiple provinces, the virus has not been detected on any dairy farms in Canada.

How do we know that our dairy cows are not infected?

The Canadian Food Inspection Agency is testing raw milk arriving at processing plants in each province for the avian influenza virus.

We also test pasteurized retail milk samples.

Tam said milk testing, similar to wastewater testing for viruses such as COVID-19 and seasonal influenza, will provide an “early warning” signal if H5N1 reaches Canadian dairy farms. He said it was intended to.

Even if H5N1 gets into milk, is it safe to drink?

The Canadian Food Inspection Agency says yes, as long as the milk is pasteurized.

“In Canada, milk must be pasteurized before it can be sold. The pasteurization process kills harmful bacteria and viruses, including HPAI (highly pathogenic avian influenza), making milk and dairy products safe to drink and eat.” ” states the CFIA website.

Is it safe to eat chicken, eggs, and beef?

Yes, it is possible as long as it is fully cooked.

Where is the infected poultry farm?

As of Nov. 13, there were 28 infected poultry stores in British Columbia, two in Alberta and one in Saskatchewan, according to the Canadian Food Inspection Agency website.

Shayan Sharif, a professor of pathology at Ontario Veterinary Medicine at the University of Guelph, said he believes the H5N1 virus will reach poultry farms in other provinces.

“I hope I'm proven wrong… but I think we'll probably head east in the not-too-distant future,” he told The Canadian Press.

What do you do if you have an H5N1 infection on your farm?

Farmers must notify the CFIA if they suspect that their birds or livestock are infected with avian influenza.

Sharif said all poultry on farms that test positive for H5N1 must be killed. But there's no need to kill the cow, he says.

The virus can be spread through direct contact with infected animals, but it can also spread through contaminated barns and other environments.

Mr Sharif said 'biosecurity' was one of the most important ways to stop the spread of avian influenza among farms.

This means workers must wear personal protective equipment and change clothing when entering or leaving farms where avian influenza has been detected.

It also means not sharing equipment between farms and cleaning and disinfecting trucks delivering supplies and feed, he said.

Sharif said he supports Finland's offer of avian influenza vaccines to farm workers.

Health Canada has approved three influenza vaccines that can be used to prevent H5N1 avian influenza.

Although these vaccines are not currently available here, Tam said public health officials are “very interested” in learning from Finland and that they are investigating the use of H5N1 vaccines as they monitor avian influenza activity in Canada. He said he is actively considering the possibility.

This report by The Canadian Press was first published Nov. 15, 2024.

Canadian Press health coverage is supported through a partnership with the Canadian Medical Association. CP is solely responsible for this content.