H5N1 avian influenza, more commonly known as bird flu, has infected more than 100 million birds in the U.S. and almost 500 dairy cattle herds across 15 states. The virus has popped up in mammals including elephant seals,

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.

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.

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.

It's not clear how the British Columbia teenager picked up the virus, which has been detected recently in wild birds and poultry in the province, a health official said.

Amid an ongoing outbreak of bird flu in American dairy herds and poultry flocks, Canadian officials have announced that a teen in British Columbia has been hospitalized in critical condition with what is believed to be bird flu.

A Canadian teenager is hospitalized in critical condition with bird flu, health officials reported Tuesday. The teen has been receiving care at BC Children’s Hospital in Vancouver since Friday, the same day an initial test came back positive for H5 influenza.