Agriculture officials are trying to limit the damage, but it's unclear whether quarantines, transportation bans and mass killings will stop the spread, said Joseph Hess, a poultry science professor at Auburn University.
The disease was first confirmed in southern Tennessee earlier this month and has since been detected in northern Alabama and western Kentucky.
"We're at the point where it's a little here and a little there. It could fade away, but it could blow up into something bigger," said Hess, who also works with the Alabama Cooperative Extension System.
State officials say no infected birds have entered the nation's poultry supply, and the U.S. food chain isn't at risk.
The Kentucky Department of Agriculture said last week that it was temporarily banning the transportation of poultry after a low-pathogenic form of the disease was found in a commercial flock of 22,000 hens in western Kentucky. The farm was placed under quarantine and the birds were killed.
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