Bioterrorism is the use or threatened use of microorganisms or toxins to produce disease and/or death in humans, animals or plants. Bioterrorists undertake such actions to create fear and intimidate governments in the pursuit of idealological, political, or religious goals. Bioterrorism is insidious because biological agents are hard to detect upon covert release, they are nondiscriminate killers, and terrorists can protect themselves from the release and escape prior to the effect as it may take days to produce disease.
Unlike conventional weapons, bioweapons are a relatively inexpensive means of eradicating people from an environment while preserving stuctures. At least 17 nations have offensive bioweapons programs. With the collapse of the Soviet Union and economic instability, the possibility exists that their research into weaponizing bioagents has been sold to terrorists. Weaponizing consists of processes designed to enhance delivery, stability, infectivity and/or lethality. Aerosol delivery is the most likely means of delivery for bioagents followed by water or food borne means, which are less likely due to logistics. In order to be delivered effectively by aerosol to the oral and nasal passages, particles must be very small (10 microns). They must be even smaller if they are to reach the lungs by inhalation. Once released, bioagents are subject to degradation by UV light, temperature or humidity and dissemination and dilution by winds. Water or food borne routes present a higher degree of difficulty for the delivery of bioagents.
Epidemiologically, unusually high rates of illness or unusual disease should raise red flags. More severe disease than might be expected for a specific pathogen or unusual routes of exposure may point to bioterrorism. Additionally, infections with strains having unusual antibiotic resistance or a pathogen not endemic to that geographic area or outside its normal transmission season are suspicious. Increased awareness is warranted whenever intelligence suggests an attack may be possible and immenent. Indeed, in the face of credible threats all things out of the normal must be evaluated as possible bioterrorism events.
The aggressive potential of any bioagent is based on their ability to multiply in the host as well as virulence, lethality, stability, infectivity, pathogenicity, mode of transmission and incubation period. Potential bioagents are evaluated based on their aggressive potential, availability and ease of production. The following categories have been created by the Centers for Disease Control in Atlanta.
- Can be easily disseminated or transmitted person to person
- Cause high rates of mortality
- Could cause public panic
- Require special attention and public health awareness
- Moderately easy to disseminate
- Moderate morbidity and lower mortality
- Require enhanced disease surveillance
Emerging pathogens; based on availability, ease of production and dissemination, and potential for high morbidity and mortality.