Canada Reports First Human Case Of H5N1 Bird Flu

A Canadian teenager has been hospitalized with bird flu, the first human case of H5N1 in the current ... [+] outbreak detected in the country.

A teenager in British Columbia, Canada has been hospitalized with a presumed case of H5N1 bird flu, the first detected human case in the country from the recent outbreak. The individual is presumed to have contracted the virus, also called avian flu or avian influenza, from exposure to wild birds, but testing is ongoing to confirm this.

“Our thoughts are with this young person and their family during this difficult time,” said Dr. Bonnie Henry, B.C.’s provincial health officer in a news release. “This is a rare event, and while it is the first detected case of H5 in a person in B.C. or in Canada, there have been a small number of human cases in the U.S. and elsewhere, which is why we are conducting a thorough investigation to fully understand the source of exposure here in B.C,” said Henry.

All close contacts of the infected individual are being contacted and investigations are underway to figure out how the teenager was infected. Canada has been testing wild birds, finding strains of the virus similar to those circulating in both parts of the U.S. and Japan, but this is the first time the virus has been found in a human. The case represents only Canada’s second ever detected case of H5N1, after a traveller returning from China in 2014 died from the disease.

Since March 2024, the U.S. department of agriculture has confirmed outbreaks in 440 dairy cattle herds across 15 states, with the outbreak continuing. The virus has also been detected in 45 commercial poultry flocks and 30 backyard flocks. Canada has been testing milk and livestock, but unlike in the U.S. there has been no confirmed cases of the same H5N1 virus from the U.S. in either cattle or poultry farms in Canada.

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

The first case of the current dominant H5N1 strain in humans in the U.S. was detected in April 2024, with 44 cases in total now detected, according to the U.S. CDC. These cases are thought to mostly come from either contact with infected dairy cows, poultry farms or wild birds. However this number is likely to be a significant underestimate, with many cases likely to go undetected. Earlier this month, the virus was detected in wastewater testing in a Los Angeles County, suggesting that infections in humans may be far more prevalent than believed.

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