Canada reports first human case of H5N1 bird flu

A teenager in British Columbia, Canada, has been hospitalized with a suspected case of H5N1 bird flu, the first confirmed human case in the country since the recent outbreak. It is suspected that the person became infected with the virus, also called avian influenza or bird flu, through contact with wild birds. However, tests are currently being carried out to confirm this.

“Our thoughts are with this young person and his family at this difficult time,” said Dr. BC Provincial Health Officer Bonnie Henry said in a news release. “This is a rare event and although this is the first case of H5 detected in a person in British Columbia or Canada, there have only been a small number of human cases in the United States and elsewhere, which is why we are conducting a thorough investigation.” to fully understand the source of exposure here in B.C.,” Henry said.

All close contacts of the infected person are being contacted and investigations are underway to find out how the teenager became infected. Canada has tested wild birds and found virus strains similar to those circulating in the United States and Japan. However, this is the first time the virus has been found in a human. The case represents only the second case of H5N1 ever detected in Canada, after a traveler returning from China in 2014 died of the disease.

As of March 2024, the U.S. Department of Agriculture has confirmed outbreaks in 440 dairy herds in 15 states, and the outbreak is ongoing. The virus was also detected in 45 commercial poultry flocks and 30 backyard flocks. Canada has conducted dairy and livestock testing, but unlike the United States, there have been no confirmed cases of the same H5N1 virus from the United States on either cattle or poultry farms in Canada.

According to the World Health Organization, 903 human cases of H5N1 have been detected in five countries since 2003. Of these cases, 464 were fatal, for a fatality rate of 51%. However, this is likely an overestimation because people who are more ill are more likely to be hospitalized and tested for H5N1. Many of the symptoms of H5N1 overlap with those of other viral infections such as influenza and Covid-19, meaning people may not know they are infected with H5N1.

The first case of the currently dominant H5N1 strain in humans in the USA was discovered in April 2024; according to the US CDC, there are now a total of 44 cases. These cases are believed to most often result from contact with infected dairy cows, poultry farms or wild birds. However, this number is likely to be significantly underestimated as many cases are likely to remain undetected. Earlier this month, the virus was discovered during wastewater testing in a Los Angeles county, suggesting that human infections may be far more common than previously thought.