Bioterrorism

Terrorism involving the intentional release or dissemination of biological agents that

are harmful to humans. These agents may be in a naturally occurring or a humanmodified

form. For the use of this method in warfare, see Biological warfare. Biological

diseases and the agents that might be used for terrorism have been listed by the US

Centers for Disease Control and Prevention. (CDC)

These agents include viruses, bacteria, rickettsiae (microorganisms that have traits

common to both bacterial and viruses), fungi, and biological toxins. Bioterrorism agents

can be separated into three categories, depending on how easily they can be spread

and the severity of illness or death they cause. Category A agents are considered the

highest risk and Category C agents are those that are considered emerging threats for

disease.

Category A agents pose high risk to national security because they can be easily

disseminated or transmitted from person to person; cause high mortality, with the

potential for major public health impact; might cause public panic and social disruption;

and require special action for public health preparedness. Examples of Category A

diseases include anthrax, botulism, plague, smallpox (variola), tularemia, and viral

hemorrhagic fevers due tofiloviruses (e.g., Ebola, Marburg) and arenaviruses (e.g.,

Lassa, Machupo)

Category B agents are moderately easy to disseminate; cause moderate morbidity and

low mortality; and require specific enhancements of the diagnostic capacity and

enhanced disease surveillance. Examples of Category B diseases include Brucellosis,

Epsilon toxin of Clostridium perfringens, food safety threats (e.g., Salmonella species,

Escherichia coli O157:H7, Shigella), Glanders (Burkholderia mallei), Melioidosis

(Burkholderia pseudomallei), Psittacosis, Q fever, Ricin toxin from Ricinus communis

(castor beans), Staphylococcal enterotoxin B, Typhus fever (Rickettsia prowazekii),

Viral encephalitis due to alphaviruses (e.g., Venezuelan equine encephalitis, eastern

equine encephalitis, western equine encephalitis) and water safety threats (e.g., Vibrio

cholerae, Cryptosporidium parvum).

Category C agents are emerging pathogens that could be engineered for mass

dissemination in the future because of their availability; ease of production and

dissemination; and potential for high morbidity and mortality and major health impact.

Examples of Category C diseases include Nipah virus, Hantavirus, tickborne

hemorrhagic fever and encephalitis viruses, Yellow fever, and Tuberculosis (multidrug-

resistant TB).

The act of bioterrorism can range from a simple hoax to the actual use of biological

weapons, also referred to as agents. Biological agents may be used for an isolated

assassination, as well as to cause incapacitation or death to thousands. If the

environment is contaminated, a long-term threat to the population could be created.

The use of biological agents is not a new concept, and history is filled with examples of

their use. In addition, an accidental release of biological agents is possible.