A teenager in British Columbia was hospitalized in critical condition with the disease, and officials were working to find out how the person was exposed to the virus.

British Columbia health officials have yet to identify a likely source of the infection, though none of the teen's contacts have tested positive for the virus so far.

Canadian health officials have confirmed bird flu in a British Columbia teen. The Public Health Agency of Canada said Wednesday that tests showed the virus involved was related to a bird flu outbreak in poultry in the province.