Risks and benefits of preexposure and postexposure smallpox vaccination.
This article presents a model and decision criteria for evaluating a person's risk of pre- or postexposure smallpox vaccination in light of serious vaccine-related adverse events (death, postvaccine encephalitis and progressive vaccinia). Even at a 1-in-10 risk of 1,000 initial smallpox cases, a person in a population of 280 million has a greater risk for serious vaccine-related adverse events than a risk for smallpox. For a healthcare worker to accept preexposure vaccination, the risk for contact with an infectious smallpox case-patient must be >1 in 100, and the probability of 1,000 initial cases must be >1 in 1,000. A member of an investigation team would accept preexposure vaccination if his or her anticipated risk of contact is 1 in 2.5 and the risk of attack is assumed to be >1 in 16,000. The only circumstances in which postexposure vaccination would not be accepted are the following: if vaccine efficacy were <1%, the risk of transmission were <1%, and (simultaneously) the risk for serious vaccine-related adverse events were >1 in 5,000.
Meltzer
Martin I
MI
Centers for Disease Control and Prevention, Atlanta, Georgia 30345, USA. qzm4@cdc.gov
D001294:Attitude to Health; D006801:Humans; D016015:Logistic Models; D018570:Risk Assessment / Q000379:methods*; D012899:Smallpox / Q000517:prevention & control; D012900:Smallpox Vaccine / Q000009:adverse effects*; D014481:United States
D012900:Smallpox Vaccine