Honors fraternity Phi Beta Kappa invited three panelists who have dealt directly with biological agents in laboratories. The panelists suggested various forms that a biological attack on the United States could take.
"The next threat is going to be the food supply," said Robert Ryder, director of the UNC Center for Biopreparedness, as he spoke to a circle of 23 UNC and high school students.
"We as a nation eat the same food, and it is made in the same place, and it is distributed widely. People can use that, and I think they will use that."
In one scenario, Ryder suggested that someone could steal botulism toxin from a lab and pour half a cup of the toxin in an unlocked tanker truck carrying milk from a dairy farm.
That milk could then be used in making ice cream, which has nationwide distribution. People could then become ill from the toxin throughout an entire region, Ryder said.
"When would the alarm bell go off?" Ryder asked, referring to recognition of the disease. "I want to have a system in place to make that bell ring so I can pull that ice cream off the shelf."
Besides the food distribution system in this country, Ryder also spoke of global travel as an enabler that allows a biological agent to be transported.
"It would be quite easy to put some smallpox in (the Washington, D.C., subway center)," Ryder said. "The incubation period for smallpox is 12 to 14 days, and in 12 to 14 days those people are going to be all over the world."
Peter Gilligan, director of the clinical microbiology and immunology lab at UNC Hospitals, said smallpox is the potential disease weapon that he finds most troubling.