Category A agents are the highest-priority agents because they: - Can be easily disseminated or spread person-to-person
- Can be extremely lethal
- Have the potential for serious public health impact
- Can potentially cause public panic and lead to social disruption
Category A organisms include: - Bacillus anthracis (anthrax)
- Clostridium botulinum (botulism)
- Yersinia pestis (plague)
- Variola major (smallpox) and other pox viruses
- Francisella tularensis (tularemia)
- Viral hemorrhagic fevers
Category B organisms are the second-highest-priority agents because they: - Are moderately easy to disseminate
- Usually result in moderate morbidity
- Are generally less lethal
Category B organisms include: - Burkholderia pseudomallei
- Coxiella burnetti (Q fever)
- Brucella species (brucellosis)
- Burkholderia mallei (glanders)
- Ricin toxin (from Ricinus communis)
- Epsilon toxin of Clostridium perfringens
- Staphylococcus enterotoxin B
- Typhus fever (Rickettsia prowazekii)
- Other food and waterborne pathogens
Category C organisms are defined as: - Emerging infectious disease threats that potentially could be engineered for future dissemination
Category C organisms include: - Nipah virus
- Additional hantaviruses
See also the CDC's list of Biological Agents/Diseases and NIAID's Category A, B & C Priority Pathogens. | 