Table 2.

National Institute of Allergy and Infectious Diseases emerging infectious diseases/pathogens

Definition	Pathogens
Category A: Organisms/biological agents that pose the highest risk to national security and public health • Can be easily disseminated or transmitted from person to person • Result in high mortalities; potential for major public health impact • Might cause public panic and social disruption • Require special action for public health preparedness	Category A Priority Pathogens • Bacillus anthracis (anthrax) • Clostridium botulinum toxin (botulism) • Yersinia pestis (plague) • Variola major (smallpox) and other related pox viruses • Francisella tularensis (tularemia) • Viral hemorrhagic fevers: Arenaviruses, Bunyaviruses, Flaviviruses, Filoviruses
Category B: Second highest priority organisms/biological agents • Moderately easy to disseminate • Result in moderate morbidities and low mortalities • Require specific enhancements for diagnostic capacity and enhanced disease surveillance	Category B Select Priority Pathogens • Burkholderia pseudomallei (melioidosis) • Coxiella burnetii (Q fever) • Brucella species (brucellosis) • Ricin toxin (Clostridium perfringens) • Staphylococcus enterotoxin B • Typhus fever (Rickettsia prowazekii) • Foodborne and water-borne pathogens: bacteria (eg, E coli, shigella; salmonella, campylobacter); viruses (eg, hepatitis A); protozoa (eg, Cryptosporidium parvum, Giardia lamblia), fungi • Mosquito-borne viruses (eg, West Nile, yellow fever, chikungunya, Zika)
Category C: Third highest priority. Includes emerging pathogens that could be engineered for mass dissemination in the future because of • Availability • Ease of production and dissemination • Potential for high morbidities and mortalities and major health impact	Category C Select Priority Pathogens • Nipah and Hendra viruses • Additional hantaviruses • Tick-borne hemorrhagic fever viruses (Bunyaviruses, Flaviviruses) • Tick-borne encephalitis complex flaviviruses • Tuberculosis, including drug-resistant tuberculosis • Influenza virus • Other rickettsias • Rabies virus • Severe acute respiratory syndrome associated coronavirus

Data from NIH National Institute of Allergy and Infectious Diseases. NIAID emerging infectious diseases/pathogens. Available at: https://www.niaid.nih.gov/research/emerging-infectious-diseases-pathogens. Accessed July 26, 2018.