Bird flu risk to humans an enormous concern, WHO says. Heres what to know – National [Video]

The World Health Organization’s top scientist says there is “enormous concern” about the risk of spread of the H5N1 bird flu to humans, but at least one infectious disease expert says Canadians don’t need to worry about changing their daily routine just yet.

Speaking to reporters in Geneva on Thursday, Jeremy Farrar’s warning comes just two weeks after the U.S. Centers for Disease Control and Prevention (CDC) reported a human case of avian influenza in a person who had contact with dairy cows in Texas.

Avian flu, also known as bird flu, is caused by influenza viruses that spread among wild aquatic birds and can infect domestic poultry and other animal species.

The H5N1 avian influenza virus first emerged in southern China in 1996 and has been causing outbreaks in birds since then.

Numerous mammals have been infected over the years, but the recent addition of infection in dairy cattle raised …