The teenager who is sick with the first-ever human case of avian influenza acquired in Canada is in hospital in critical condition, provincial health officer Dr. Bonnie Henry said Tuesday.

“Our thoughts continue to be with the person and their family in this most difficult time,” she said in an update on the situation.

The young person is suffering from acute respiratory distress syndrome caused by inflammation in the lungs, Henry later added. They were admitted to BC Children’s Hospital Friday night, after they first started experiencing symptoms on Nov. 2, which were an eye infection, a fever and a cough.

Officials are not releasing the exact age or gender of the teenager, who lives in the Fraser Health region, for privacy reasons.

Henry said officials in B.C. are still waiting on confirmation from a national laboratory, but the assumption is the virus is H5N1, as that strain has been spreading in wild birds and poultry in North America.

About three dozen people who were in contact with the infected young person have been tested for avian influenza and given an antiviral medication to prevent symptoms should they be infected, but Henry said no other cases have been identified so far.

Humans can be infected with bird flu by inhaling the virus in aerosols and droplets, which get into H5 receptors in the eyes, the back of the throat, nose, or deep in the lungs, Henry said.

Details of exposure unknown

Henry said public health is currently trying to figure out where exactly the teenager was exposed and they’re following up on a number of leads, but it doesn’t appear the infection happened on a poultry farm.

“This person does not live on a farm, and there is no contact with any poultry farming, any other farming in their area or in the family, so theres no obvious quick connection to a farm or exposure to wild birds, or to poultry that we can detect at this time,” Henry said. She added the individual came into contact with dogs, cats, and even reptiles, but no birds as far as officials are aware—and none of the animals they’ve tested for the virus so far have come back positive.

As of Tuesday, 26 facilities in B.C. are currently infected with avian influenza, mostly in the Fraser Valley. More than 6 million birds have been culled on B.C. farms due to H5N1 since 2022.

There have been 46 confirmed cases of H5N1 in humans in the United States, predominantly among dairy workers, where in Washington, Oregon and California hundreds of herds have been infected. The virus has so far not been detected in dairy cattle in Canada.

Henry said the U.S. cases have been mostly “very mild,” but noted that going back to early bird flu cases—about 900 people have been infected world-wide since 1997—the fatality rate has been “quite high,” particularly when children are exposed.

“Almost all of these have been traced back to direct contact with birds, sick birds or sick animals. Theres been very few that might have been transmitted from person to person,” she said. “So in some ways, this is reassuring, in that this virus doesnt seem to spread easily between people if they get infections, but it also causes very severe illness, particularly in young people.”

She noted that the only other case of avian influenza detected in Canada—a traveller who most likely acquired it in China in 2014—was also a young person who ultimately died from the illness.

“Something about our immunity as we get older seems to protect us from getting those deep lung infections that cause a more serious illness,” Henry said, adding that one hypothesis is that exposure to other N1 viruses—like H1N1 or “swine flu”—gives protection, but the exact reason remains unknown.

Henry said officials don’t currently see a risk of many people getting sick with H5N1 in B.C., but reminded everyone to stay away from sick or dead birds and keep pets away—a dog in Ontario was recently infected after eating a dead bird—to stay up to date on the influenza vaccine and stay home when sick. 

Safety precautions 

The B.C. Poultry association says facilities are taking precautions as a result bird flu cases in wild and farm birds.

“We’ve been working through this for a few years now and have developed some systems to help prevent the spread,” said spokesperson Shawn Hall.

“We added additional measures. For example, farm gates are closed so that visitors are only coming onto the farm if it’s essential, they have to come with an appointment, they have to wear PPE.”

Maple Wood Farm, a petting zoo in Metro Vancouver, is also adapting to help prevent the spread.

A spokesperson with the District of North Vancouver says all farm birds are being kept inside their pens and have stopped allowing guests to feed the birds. The farm has also set up a shoe sanitization station at the entrance.