about Epidemiology & the department

Epidemiology academic information

Epidemiology faculty

Epidemilogy resources

sites of interest to Epidemiology professionals

Last Updated

15 Oct 2002

Source: Rocky Mountain News, October 15, 2002.

Anthrax simulation 'kills' half a million

By Jim Erickson, Rocky Mountain News

COLORADO SPRINGS - More than half a million Coloradans could die after an airborne anthrax attack over Denver, according to a worst- case scenario churned out by a Pentagon computer model.

Researchers at the Heritage Foundation, a conservative think tank in Washington, D.C., obtained the computer modeling software from the Defense Department and simulated various terrorism scenarios.

In one simulation, terrorists in a small private airplane release 440 pounds of military-grade powdered anthrax over downtown Denver. Over the next 24 hours, the spores blow 126 miles eastward and expose more than 812,000 people.

Between 447,000 and 591,000 of the victims die, according to the simulation, which uses federal Defense Threat Reduction Agency data and real-time National Weather Service information.

"This is not meant to scare people," said threat assessment specialist Dexter Ingram, who demonstrated the modeling software Monday at a homeland security conference in Colorado Springs.

"We're not saying that something like this is going to happen," he said. "It's just one of the many scenarios that we played out, and some of the numbers are not that realistic."

The model makes several unrealistic assumptions that drive the mortality totals much higher than they'd be in a real-life aerial anthrax attack. For example, the model assumes that no one evacuates the affected area and that no one seeks medical help.

"No one is going to stay put for 24 hours if something like this occurs, and everyone is going to seek medical attention," said Suzanne Mencer, director of the Colorado Office of Homeland Security.

"This model, as good as it is, has to be taken with a grain of salt," said Robert A. Malson, president of the District of Columbia Hospital Association.

"Last year's anthrax attack showed how quickly we can get on top of an anthrax situation," Malson said at the workshop.

The Defense Department uses the Consequences Assessment Tool Set software to predict the effects of attacks with nuclear weapons, chemical and biological weapons, conventional bombs and so-called dirty bombs, which use conventional explosives to disperse radioactive material.

Emergency response personnel can use the CATS computer model to predict where hazardous airborne substances will move after they're released and to determine which areas would require evacuation - and possibly quarantine - after a terrorist attack.