No one wants it to happen.
But if it does, McLean County Health Department is making sure it's ready.
A full scale exercise is happening at U.S. Cellular Coliseum today.
It's the scenario of 30,000 people exposed to anthrax released through air ducts at Illinois State's Bone Student Center.
Hundreds of volunteers helped.
Health officials hypothetically had to get two rounds of antibiotics distributed to all of these people within 48 hours.
"It's very detailed, it involves media and how the public is responding," says Kera Simon with the McLean County Health Department. "It's supposed to be as real as possible so we stay on top of our game essentially. Especially at these medication dispensing sites, it's very important."
This type of scenario has also happened at twin cities hospitals and the town of normal recently.
The Illinois Department of Public Health evaluates them on response.
All of the organizations will come together and point on what went right and what could use improvement.