Wind-blown avian feces may be route of transmission for bird flu, infectious disease expert warns

Snow geese are seen during their migratory movements at the Reservoir Beaudet, in Victoriaville, Que., Wednesday, Nov. 1, 2023. THE CANADIAN PRESS/Bernard Brault

MINNEAPOLIS, Minnesotta (WCCO) -- Flu expert says bird flu virus may be spread by infected feces blowing in the wind.

Dr. Michael Osterholm is a medical detective and Director of the Center for Infectious Disease Research and Policy, or CIDRAP, at the University of Minnesota. Osterholm has nearly 50 years of investigating infectious disease outbreaks and public health threats.

Osterholm hosts a podcast at the University of Minnesota called “Osterholm Update,” where he discusses latest disease and outbreak news headlines.

On episode 175 titled, “Drinking From a Fire Hose: Are We Drowning?,” Osterholm and his co-host, Chris Dall, discuss growing concerns regarding bird flu — or H1N1 — making the jump from animals to humans.

According to Osterholm, there has been an additional 89 confirmed flocks with high path avian influenza within the last 30 days alone. Areas affected include Georgia, Indiana, Ohio, California, New York, Minnesota and Maryland.

Osterholm says that the primary kind of birds impacted by the flu is migratory waterfowl, like geese and ducks, and these birds often hang out in farm fields where they defecate. Then, the wind picks up particles of the infected feces, spreading the virus far and wide.

The problem is then exacerbated as many poultry production facilities house their poultry in barns that have little protection from the elements and are not airtight. Meaning, its easy for infected winds to reach commercial animals.

Additionally, Osterholm points out, slats on these enclosures are often opened during warm weather.

“Today, I am certain that we are seeing clouds of dust with bird feces in that, and we are beginning to see what I would consider to be almost an environmental type disease, similar to the transmission that we see with Coccidioidomycosis, what we call Valley fever, where in fact that’s a fungus that grows in the environment. And then on windy days it blows with the dust and you inhale it. I think we’re going to see the same thing with H5N1. That’s why so many of these barns are now positive,” said Osterholm on his podcast.

Now that the virus has gone airborne, Osterholm believes we’re going to start seeing more and more cases in humans with no explanation for why they occurred. Meaning, people are going to get sick without even coming in contact with the infected animal.

“I think we’re going to see more and more situations with wind driven activity where you’re going to see virus show up. What does that mean? I do not believe that the price of eggs is going to come down anytime soon, because until the poultry industry realizes they have to have airtight barns with HEPA filter intake, they’re going to continue to see this virus show up and show up and show up and show up. Unless it changes in the wildlife. It’s unless it changes in the migratory waterfowl. It’s going to continue to be a problem for them,” said Osterholm.

™ & © 2025 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.