Biological Agents

Table 1. Critical biological agent categories for public health preparedness

Biological agent(s)	Disease

Category A
Variola major	Smallpox
Bacillus anthracis	Anthrax
Yersinia pestis	Plague
Clostridium botulinum (botulinum toxins)	Botulism
Francisella tularensis	Tularemia
Filoviruses and Arenaviruses (e.g., Ebola virus, Lassa virus)	Viral hemorrhagic fevers
Category B
Coxiella burnetii	Q fever
Brucella spp.	Brucellosis
Burkholderia mallei	Glanders
Burkholderia pseudomallei	Melioidosis
Alphaviruses (VEE, EEE, WEE^a)	Encephalitis
Rickettsia prowazekii	Typhus fever
Toxins (e.g., Ricin, Staphylococcal enterotoxin B)	Toxic syndromes
Chlamydia psittaci	Psittacosis
Food safety threats (e.g., Salmonella spp., Escherichia coli O157:H7)
Water safety threats (e.g., Vibrio cholerae, Cryptosporidium parvum)
Category C
Emerging threat agents (e.g., Nipah virus, hantavirus)

^aVenezuelan equine (VEE), eastern equine (EEE), and western equine encephalomyelitis (WEE) viruses

Agents in Category A have the greatest potential for adverse public health impact with mass casualties, and most require broad-based public health preparedness efforts.

Most Category B agents also have some potential for large-scale dissemination with resultant illness, but generally cause less illness and death and therefore would be expected to have lower medical and public health impact.

Biological agents that are currently not believed to present a high bioterrorism risk to public health but which could emerge as future threats (as scientific understanding of these agents improves) were placed in Category C.

Soure: Lisa D. Rotz, Ali S. Khan, Scott R. Lillibridge, Stephen M. Ostroff, and James M. Hughes; Report Summary titled: Public Health Assessment of Potential Biological Terrorism Agents. Centers for Disease Control and Prevention.