There are many reasons why specific agents would be selected for use in bioterrorist attacks, including the following:
- Ease of availability: Biological pathogens can be obtained from nature, hospital laboratories, and university research facilities.
- Difficulty to detect: Small quantities can have potentially deadly or incapacitating effects on a susceptible population.
- Covert use of the agent: Can be spread throughout large areas by natural convection, air, or water currents.
- Ease in disseminating: Pathogens can be spread through building ventilation systems. Transportation facilities could become part of the dissemination system by carrying biological agents far from their initial source.
- Psychological impact: Biological WMDs could have a psychological impact that will go far beyond their actual effect. The very thought of exposure to a biological agent may cause many people to panic.
- Ability to tie up resources: Some biological agents can be hazardous for lengthy periods. Using these agents may require tedious, time-consuming, resource-intensive decontamination and monitoring of facilities before they can be returned to service.
- Difficulty defending against attack: It is very difficult for civilian government agencies to prepare for biological terrorist incidents. While most civilian agencies have some kind of hazardous material or HAZMAT response teams, in the event of a biological terrorist incident, these teams are likely to be challenged beyond their capability in terms of human resources and equipment.
