Concern that smallpox virus might be used as a biological weapon has
led to proposals that smallpox vaccination be offered to at least some of
the US population.1-4 In
June 2002, the US Department of Health and Human Services' Advisory Committee
on Immunization Practice recommended that vaccination be offered to limited
numbers of health care personnel who may be investigating possible cases of
smallpox and to those who might be caring for patients in selected hospitals.5 On September 23, 2002, the Centers for Disease Control
and Prevention (CDC) distributed detailed operational and logistic guidelines
for implementing a large-scale volunteer smallpox vaccination program in response
to introduction of smallpox as an act of terrorism.6 These
events raise concern about the frequency of serious adverse events, including
death, that may occur from vaccination. These have been well documented.7-13 Such
severe reactions are far more frequent following smallpox vaccination than
following any other vaccine. Most complications occur in the vaccinees themselves,
but vaccinia virus can be transmitted inadvertently from vaccinees to others,
sometimes causing serious and even fatal adverse reactions.