A teenager in Canada is critically ill with the country's first human case of H5N1 bird flu. Health officials aren't sure how the youth was exposed.

A Canadian teenager infected with bird flu — that country’s first case involving a locally acquired infection — is in critical condition and experiencing difficulty breathing, health officials said Tuesday.

British Columbia health officer Dr. Bonnie Henry shared in a news conference that a teenager, who contracted the first presumptive case of bird flu in Canada, was in critical condition after developing 'acute respiratory distress.