A teenager is in critical condition at a British Columbia children’s hospital, suffering from the first presumptive human case of the disease .
“Prior to this episode he was a healthy teenager, so no underlying conditions,” provincial health officer Bonnie Henry said at a news conference Tuesday.
“It just reminds us that in young people, this is a virus that can progress and cause quite severe disease and the deterioration that I talked about was quite rapid.”
On Saturday, British Columbia health officials said the province had detected Canada’s first human case of H5 avian influenza in a teenager.
Henry said the province is still identifying the exact strain, but assumes it is H5N1.
The World Health Organization says the risk of H5N1 to humans is low because there is no evidence of human transmission, but the virus has been found in an increasing number of animals, including cattle, in the United States.
Henry wouldn’t reveal the teen’s gender or age, but said they had done so before on Nov. 2 and were tested on Nov. 8, when they were admitted to the hospital. Symptoms included conjunctivitis, fever and cough.
They were admitted to hospital with acute respiratory distress syndrome on Tuesday, he said.
The teen had had no contact with the farm, but had been exposed to dogs, cats and reptiles, Henry said. No source of infection had been identified. “This is absolutely an ongoing investigation.”
More severe disease occurs when the virus binds to receptors deep in the lungs, he said.
Public health officials have identified and tested about three dozen contacts and found no one infected with the virus.
There is no evidence that the disease spreads easily between people. But if that were to happen, a pandemic could break out, scientists said.
In early November, the Centers for Disease Control and Prevention called for farm workers exposed to animals infected with avian influenza to be tested for the virus even if they had no symptoms.
Avian influenza has infected nearly 450 dairy farms in 15 U.S. states since March, and the CDC has identified 46 human cases of avian influenza since April.
In Canada, British Columbia has identified at least 26 affected premises across the province, Henry said Tuesday, and numerous wild birds have tested positive.
In Canada, there have been no reports of cases in dairy cattle and no evidence of avian influenza in milk samples.