Smallpox vaccination: A review, part II. Adverse events

Smallpox vaccination of health care workers, military personnel, and some first responders has begun in the United States in 2002–2003 as one aspect of biopreparedness. Full understanding of the spectrum of adverse events and of their cause, frequency, identification, prevention, and treatment is imperative. This article describes known and suspected adverse events occurring after smallpox vaccination. In part I of this series, we reviewed routine use of smallpox vaccine in primary vaccination and revaccination and outlined the normal, expected reactions [1]. In part II, we detail specific characteristics, rates of occurrence, pathogenesis, diagnosis, and treatment for adverse events that occur in some individuals after smallpox vaccination. Vaccination is generally safe and effective for prevention of smallpox. Smallpox vaccination can result in adverse reactions in individuals with and without specific, preexisting suscepti-bilities [2, 3]. Some of these reactions are benign, if frightening in appearance; some are serious but treatable; and a few ar