Bioterrorism is the deliberate release of viruses, bacteria or other germs (agents) to cause illness or death in people, animals or plants. These agents are typically found in nature, but can be altered to enhance their morbidity rate, resistant to medicines and virulence.
Biological agents can be spread through the air or water or in food. Terrorists may use biological agents because they can be difficult to detect and have incubation periods of several hours to several days.
Some bioterrorism agents, like the smallpox virus, can spread from person to person and some, like anthrax, can not.
Bioterrorism agents can be arranged into three categories, based on their virulence, severity and mortality rate. Category "A" agents are of the highest priority; whereas, Category "C" agents are considered emerging threats.
- Category "A" Diseases/Agents
The United States public health system and frontline healthcare providers must prepare for various biological agents, including those seldom seen on American soil. Six agents are recognized as high-priority; each constitutes a risk to national security because they:
- are easily disseminated or transmitted from person to person;
- result in high mortality rates and have the potential for major public health impact;
- might cause public panic and social disruption; and
- require special action for public health preparedness.
- Identified "A" Agents:
- Anthrax (Bacillus anthracis)
- Smallpox (variola major)
- Plague (Yersinia pestis)
- Viral hemorrhagic fevers
- Ebola & Marburg (filoviruses)
- Lassa & Machupo (arenaviruses)
- Botulism (Clostridium botulinum toxin)
- Tularemia (Francisella tularenisis)
- Category "B" Diseases/Agents
Those earmarked as secondary priority agents include those that:
- are fairly easy to disseminate;
- result in moderate morbidity rates and low mortality rates; and
- require specific enhancements of the Centers for Disease Control’s diagnostic capacity and enhanced disease surveillance.
- These include:
- Brucellosis (Brucella species)
- Epsilon toxin (Clostridium perfringens)
- Glanders (Burkholderia mallei)
- Melioidosis (Burkholderia pseudomallei)
- Psittacosis (Chlamydia psittaci)
- Q fever (Coxiella burnetii)
- Ricin toxin (derivative of Ricinus communis)
- Typhus fever (Rickettsia prowazekii)
- Viral encephalitis (alphaviruses)
- Venezuelan equine encephalitis
- Easter equine encephalitis
- Western equine encephalitis
- Staphylococcal enterotoxin B
- Food safety threats (e.g., Salmonella species, Escherichia coli 0157:H7,Shigella)
- Water safety threats (e.g., Vibrio cholerae, Cryptosporidium parvum)
- Category "C" Diseases/Agents
Third tier agents include nascent pathogens that could be engineered for mass dissemination in the future due to their:
- ease of production and dissemination; and
- potential for high morbidity and mortality rates and major health impact.