© 2023 Iowa Public Radio
Play Live Radio
Next Up:
0:00 0:00
Available On Air Stations

Officials Try to Contain Avian Flu as Outbreak Continues

IPR file photo by Kathleen Masterson
Some of Iowa's laying hens have been hit with avian influenza.

As the number of farms hit with avian flu grows over 100 nationwide, regulators are implementing containment plans meant to stop the virus’ spread, spare millions of at-risk birds and thousands of poultry farms.

Farms in many states, including Iowa, Missouri and Kansas, are struggling to contain an active outbreak.

“A rapid response is extremely important in an infectious disease outbreak like this,” said Jim Roth, head of the Center for Food Safety and Public Health at Iowa State University’s College of Veterinary Medicine.

The current outbreak of H5N2 avian flu is massive. While the strain isn’t dangerous to humans, officials want to contain it so it stays that way.

“This one has spread more broadly than I certainly anticipated,” Roth said. “Most people didn’t anticipate it would spread to this many premises.”

Roth explains that when the highly-contagious strain of bird flu is found, the state—in his case, the Iowa Department of Agriculture—issues a quarantine for the area within a 6 mile radius of the infected farm. Officials then have to check every bird in the quarantine zone for signs of the virus.

It’s a huge undertaking – in the nation’s No. 1 egg-laying state of Iowa, it can mean millions of birds. And it means federal and state agencies have to work together. They test eggs daily to keep any eggs with signs of infection out of grocery stores.

Beyond containing the virus, there’s another huge challenge: disposing of all the dead birds. On a farm found to have the virus, birds not killed from infection have to be euthanized.

Bill Ehm of the Iowa Department of Natural Resources says despite disaster planning, this outbreak has hit harder than expected. After birds in massive egg-laying operations succumbed, authorities were left playing catch-up.

“I’m not sure that we had fully considered the implications of this number of mortalities in this type of a layer operation where it is so concentrated,” Ehm said.

Ehm says there are four basic ways manage disposal. The birds can be composted in an enclosed shed, which works better for turkeys than laying hens. Or, they can be buried on-site with proper cover and above the water table. The other options are to incinerate, which can involve bringing a kiln to the farm, or to take the dead birds to a landfill. But movement of infected birds within a quarantine area is prohibited or highly restricted.

Large operations, like the virus-positive egg farm in Iowa that had to euthanize 3.8 million birds, will need to use multiple options. Regulators will have to consider the environmental impacts, such as air pollution from burning in a kiln, or water contamination from burial.

As outbreak continues to rage, researchers are trying to determine what else they could possibly do to prevent another.

Hongwei Xin, a professor and head of the Egg Industry Center at Iowa State, says the infected farms in Iowa were following required biosecurity protocols, like washing before entering and after exiting barns, and donning protective coveralls and boots before entering. That suggests the existing protocols may not be enough.

“So now it’s to the point that we say, maybe we should be looking closer about the air,” Xin said. “This thing potentially could be transmitted through particulate matter in the air that’s carried into the ventilation space, into the barn.”

Xin says previously barn ventilation systems weren’t thought to be a likely point of entry. Now, scientists are reconsidering.

Looking ahead, biologists will monitor migrating birds nationwide this fall in an effort to better understand how the avian flu virus is traveling.

Veterinarian Jim Roth says researchers may need to prepare a vaccine for this strain of bird flu, which is expensive, and administering it is labor intensive.

“(A) vaccine isn’t a solution that we would want to go to quickly,” Roth said. “Only if we really needed to because so many flocks are infected that we can’t control it or it threatens our food supply.”

In the Midwest, researchers are hopeful this is the worst outbreak they will face. But when temperatures dip again after the summer, poultry will be as vulnerable as ever. 

Amy Mayer is a reporter based in Ames