Q and A with the experts: Bird flu spillover to mammals a cause for concern

Thursday, February 16, 2023
Flock of ducks

The World Health Organization recently stated that the spillover to mammals of H5N1 influenza—commonly known as bird flu—should be monitored closely, and we need to be prepared to face infection in humans. Dr. Christine Dupont, a continuing lecturer in the Department of Biology at the University of Waterloo, is an expert on infectious disease in animals. 

Headshot of Christine Dupont

This outbreak of bird flu is affecting domesticated and wild bird populations worldwide. How would you characterize it?

This strain doesn’t seem like a regular bird influenza. It’s referred to as highly pathogenic avian influenza. Bird influenza is common, and these viruses evolve quickly. The big picture is that many influenza viruses, like this H5N1 bird flu, come from aquatic birds. It’s monitored intensely because they are potential pandemic viruses.

What is the concern about a jump to humans?

Spillover events are a worry, especially when you’ve got a virus like this that’s highly contagious among birds and causing infection in a lot of different organ tissues. And if it has been moving into other animal species, that means it could also not just jump the tissue barrier, but the species barrier. We know in the past that every pandemic we’ve had with influenza, like the swine flu and the Spanish flu, had their origins from spillover events that can all trace back to aquatic birds.

What should people do if they come into contact with sick or dead birds?

As migratory birds are moving and breeding, there’s probably going to be another peak of bird flu, and there may be sick or dead birds in the area. People shouldn’t be touching those, but we shouldn’t be leaving them there either because that increases the chances that a mammal or another bird might eat them. There’s a phone number people can call for someone to pick up the carcasses or deal with the sick birds. They are available on the website of the Canadian Wildlife Health Cooperative.