Another cause for concern: flu season is underway in the U.S., and as seasonal influenza virus goes around, “humans, ourselves, could be a mixing vessel,” Davis says. If a person were simultaneously infected with bird flu and seasonal flu, the two viruses could theoretically combine to create a more transmissible strain.

Health officials on Wednesday confirmed bird flu in a British Columbia teen and said the virus was related to a poultry outbreak in the province. Initial testing had indicated the teenager's infection was from bird flu and was confirmed in further testing,

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.