22 million birds have already been killed in the U.S. to slow the spread of the flu, which is crunching already-stressed supply chains.
The risk of major outbreak in human population is “extremely low,” authorities say.
More than 35,000 birds will be culled to contain the avian influenza outbreak.
The virus, which can spread between humans, has killed at least four people.
This year's outbreak is more deadly than every other year combined.
“It’s just a matter of when it happens, how it happens, and how deadly it's going to be.”
A new strain of avian influenza infected thousands of birds in Indiana, leading to a controversial method of euthanasia
In a ventilation shutdown, the air systems in a chicken house are turned off, causing the birds to slowly overheat and suffocate.
US egg producers are still reeling from a bird flu outbreak that killed more than 48 million chickens and turkeys in the first half of 2015.