Viruses and the Threat of Bioterrorism


Viruses can be used by both States and terrorists as biological weapons, but using them on a wide scale requires considerable technical knowledge and facilities. Many viruses can be spread by aerosols, potentially infecting large populations. Various agents have been proposed as potential weapons, but smallpox has received the greatest attention and was successfully weaponised by the Soviet Union. Smallpox vaccine has been stockpiled and new drugs and vaccines developed. Other potential agents suggested in the literature include Ebola and Marburg viruses, although these are very difficult to produce in quantity. Terrorists could however use any agent and rarely follow textbook scenarios. In response to the threat of bioterrorism a substantial research and public health infrastructure has been created, which could be useful in dealing with natural events. The main defence is education of clinicians and the public as the greatest effect of these weapons is fear and panic.

Key Concepts:

  • Viruses are potential biological weapons, and many viruses are infectious by the aerosol route even if they are normally transmitted by vectors.

  • Smallpox has received most attention as a potential biological threat.

  • Knowledge, skills, research and public health infrastructure are the best defence for bioterrorism.

  • Standard principles of infection control and public health apply to bioterrorist incidents.

  • Nature is the greatest bioterrorist and the infrastructure developed for deliberate acts supports real events.

Keywords: bioterrorism; smallpox; haemorrhagic fever; preparedness; vaccine; antiviral; aerosol

Figure 1.

The outbreak of smallpox in the former Yugoslavia from a single case who infected his immediate friends and carers in 1972. The exact total of cases is unknown, but there were at least 165 people infected. Redrawn with permission from Figure 23.7 in Fenner et al. .

Figure 2.

Renwick Smallpox hospital on Roosevelt Island, East River, New York. Isolation hospitals were a key part of the control of infectious diseases in the late nineteenth and early twentieth centuries, and smallpox hospitals were maintained in England until the 1970s.

Figure 3.

UK stocks of freeze dried sheep's lymph vaccine for smallpox. These 50 dose ampoules were reconstituted with the fluid in the double ended ampoule and administered with a bifurcated needle.

Figure 4.

A smallpox “take” reaction. Note the forming vesicle which contains live vaccinia virus.



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Brooks, Timothy JG(Feb 2012) Viruses and the Threat of Bioterrorism. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0003368.pub2]