If terrorists use biological warfare agents against the United States, people in Selma could be killed, even if the attack is initiated in Europe.

That was the sobering message Dr. James A. Johnson of Selma gave the Selma Rotary Club Monday when he spoke about how terrorists could use germ warfare to kill Americans.

Johnson works in the field of medical social science. He travels abroad often, working with the World Health Organization in Geneva. He is also part of the faculty of the Medical University of South Carolina and the Dow College of Health Professions. This summer, he spoke at a global summit on bioterrorism held in Rome.

Recently, his work has shifted to how the United States can prepare for a biological terrorist attack, namely smallpox.

Johnson said that if terrorists could deliver smallpox through an aerosol method in an airport, then people could be affected all over the world.

For example, he said if the germ were released in, say, a Paris airport, infected travelers heading to airports in New York, Atlanta and Chicago would bring the germ in the United States.

Although those people would show no signs of the virus for up to two weeks, they would be capable of infecting others with the germ. Travelers moving through airports that contained infected individuals could pick up the germ and take it to other parts of the United States, even rural areas like Selma.

Johnson estimated that smallpox could kill as many as six out of 10 people it infected. Others would be permanently scarred.

For the last 20 years, there have been no cases of smallpox worldwide because the infection was eliminated through immunizations. Many Americans were immunized for smallpox, but inoculations stopped once the disease was no longer reported.

Johnson said anyone who was immunized more than 20 years ago would have little immunity left.

Johnson said smallpox is known to exist at the Center for Disease Control in Atlanta and at a lab in the former Soviet Union. Some speculate that the virus could have been stolen or purchased when the Soviet Union was collapsing.

Johnson said former Soviet scientists were hired by Iraq after the Soviet Union collapsed.

Johnson said the Bush administration has ordered smallpox vaccine production, estimating that the United States has around 20 million doses on hand at this time.

He also said terrorists could impact rural areas and rural economies by infecting cattle with mad cow disease and by spraying food crops.