Dr. Shayan Sharif weighs in on avian influenza risk

CBC News: The National reports on four things to watch as birds migrate back north this spring. University of Guelph immunology professor Dr. Shayan Sharif spoke with the show about how the virus mutates and could spark a pandemic. "It can change its genetic structure in a matter of days," he says in the interview.

Joanna Sawicki, technical supervisor of the virology section at the Animal Health Laboratory, spoke to the show about the lab's daily testing for the H5N1 virus.

Watch the episode: Bird flu outbreaks: 4 things to watch as birds migrate back north YouTube