A woman from British Columbia has become the first person in North American to have a confirmed case of avian influenza, the Public Health Agency of Canada reported. The case appears to be unrelated to recent findings of avian influenza in Canadian birds, however, as the woman and her husband had recently returned from a trip to China.
According to a Globe and Mail report, the couple became ill with flu-like symptoms shortly after returning from a trip to China on January 12.
Tests confirmed that the woman has H7N9 avian influenza. The man, who also became ill, is suspected to have the same strain of the virus, although it has not yet been confirmed.
The couple is isolated at home and are already recovering, public-health officials said. People who have regular contact with the couple are also being monitored for symptoms.
“I want to emphasize that the risk to Canadians is very low because there is no evidence of sustained human transmission of H7N9,” said Gregory Taylor, Canada’s chief public health officer. “This particular strain of H7N9 has not been found in wild or domestic birds in Canada. The virus H7N9 is not like H5N1 avian influenza. H5N1 transmits much more easily between birds and people and those infected usually have more severe illness.”
H7N9, a subtype of influenza that had been found in birds in the past, was first discovered in humans in China in March, 2013. Since then, about 500 human cases of the strain have been documented in China. In its most recent formal assessment of the risk posed by H7N9, published in October 2014, the World Health Organization found 453 laboratory-confirmed cases of the strain and 175 deaths.
While Canadian health officials believe the virus was contracted in China, exactly how it spread remains uncertain. The couple did not visit any Chinese farms or live poultry markets, which are common places for H7N9 to spread from birds to humans. They were part of an organized tour for part of their trip, but also traveled on their own.