Biological agents

The organisms which are most likely to be used as biological threat agents can be grouped as Category A or B.

Category A Diseases / Agents

• Are easily disseminated or transmitted from person-to-person
• Have high mortality rates and potential for major public health impact
• Might cause public panic and social disruption
• Require special action for public health preparedness

Diseases in this category include:

• Anthrax
• Smallpox
• Botulism
• Plague
• Tularemia
• Viral Haemorrhagic Fevers

Category B Diseases / Agents

• Are moderately easy to disseminate
• Have moderate morbidity rates and low mortality rates
• Require enhancement of both diagnostic capacity and disease surveillance

Diseases in this category include:

• Glanders
• Melioidosis
• Brucellosis
• Q fever
• Psittacosis

Links to further information for some of these agents can be found on the disease specific guidance pages.

See also: biological releases page andCardinal Signs and Tips (PDF, 171 KB)
Unusual Illness, including Deliberate or Accidental Releases: Cardinal Signs and Tips for key Biological Agents v2.2 Feb 2011

Last reviewed: 15 March 2012