Bioterrorism

What’s the Problem?

The word “bioterrorism” refers to biological agents (microbes or toxins) used as weapons to further personal or political agendas. Acts of bioterrorism range from a single exposure directed at an individual by another individual to government-sponsored biological warfare resulting in mass casualties. Bioterrorism differs from other methods of terrorism in that the materials needed to make an effective biological agent are readily available, require little specialized knowledge and are inexpensive to produce. Until the aftermath of 9/11, few instances of bioterrorism were documented in the U.S.

A bioterrorist attack could be caused by virtually any pathogenic microorganism. The agents of greatest concern are anthrax (a bacterium) and smallpox (a virus). Both can be lethal. Anthrax is not communicable while smallpox is readily transmitted from person to person. In humans, the three forms of anthrax are inhalational, cutaneous and intestinal. Symptoms vary depending upon how the person was exposed but generally occur within 7 days of the exposure. Initial symptoms of inhalational anthrax may resemble the flu. If untreated, symptoms will progress to breathing difficulties and eventual shock. The incubation period for smallpox is 7 to 17 days following exposure. Symptoms include high fever, fatigue, and head and back pain. A characteristic rash follows in 2 to 3 days.

Who’s at Risk?

In the U.S., the risk of contracting anthrax is extremely low. The intentional release of anthrax following the events of 9/11 resulted in only twenty-two recognized cases of cutaneous and inhalational anthrax. Any risk for inhalational anthrax due to cross-contaminated mail is also very low, even for postal workers. The possibility does exist, however, that if anthrax was dispersed in a public place, a large number of people could be affected. Smallpox has not occurred in the U.S. since 1949. If the virus was intentionally released, the number of people affected could run to the tens of thousands.

Can It Be Prevented?

Bioterrorism differs from other methods of terrorism in that the effects are not always immediately apparent. An attack may be difficult to distinguish from a naturally occurring infectious disease outbreak. The first evidence of an attack will be in hospital emergency rooms where the proper diagnosis will be essential in treating and preventing the spread of the disease. In the event of intentional anthrax distribution, people at risk should take a 60-day course of prophylactic antibiotics, either doxycycline or ciprofloxacin. Vaccination against smallpox is not recommended to prevent the disease in the general public. In people exposed to smallpox, however, the vaccine can lessen the severity of, or even prevent, illness if given within 4 days of exposure. The U.S. has a supply of vaccine for emergency use.

The Bottom Line

A story about bioterrorism carries inherent drama but also certain responsibilities. A story can raise concerns and heighten the public’s awareness of the topic or it could cause alarm and panic. And because biological materials are inexpensive and readily available, some thought should be given to whether or not the show will give ideas to potential terrorists. If a person thinks they have been exposed to a biological incident or they suspect a biological threat is planned, they should contact their local health department and/or their local police department. Either of these agencies will promptly notify the FBI, which is responsible for coordinating interagency investigation of bioterrorism. The symptoms for early inhalational anthrax resemble those of the common cold or flu. Anthrax is diagnosed by isolating B. anthracis from the infected person or through other diagnostic tests. The fatality rate for cutaneous anthrax is about 20%; for inhalational anthrax the rate is closer to 75%. Smallpox is spread from person to person via airborne saliva droplets. The majority of people infected with smallpox do recover. There is a fatality rate of approximately 30%.

Case Examples

1. A religious cult has established a base outside town. The cult has applied for a charter to start its own publicly funded school. It’s already been voted down once. The charter school is again on the ballot. On election day, hundreds of townspeople become ill and are too sick to get out to vote. In searching the cult headquarters on another matter, a vial of Salmonella typhimurium is found. After questioning by the police, one of the cult members reveals that the salmonella was used to intentionally contaminate local restaurant salad bars with the aim of limiting the number of people who would vote against the charter school.
2. The E.R. is flooded with people experiencing cold and flu symptoms; some people are having difficulty breathing. Police get a phone call from someone claiming they released anthrax in a downtown office building. One of the doctors diagnoses inhalational anthrax. No one on the staff has ever seen a case before. The E.R. is thrown into a panic. Authorities are notified. At shift change, a doctor trained in the Soviet Union comes in and is informed of the case. He has experience with treating anthrax. After viewing a chest x-ray and CT, he’s convinced the problem is not anthrax. Cultures come back negative for B. anthracis, proving the doctor was correct in his diagnosis.