Smallpox Vaccine: Contraindications, Administration, and Adverse Reactions

Since the terrorist attacks of September 11, 2001, and the anthrax exposures in the following weeks, concern that smallpox could be used as a biologic weapon has increased. Public health departments and the U.S. military have begun the process of vaccinating soldiers and civilian first-responders. Smallpox vaccination carries some serious risks: approximately one in 1 million primary vaccinees and one in 4 million revaccinees will die from adverse vaccine reactions. The most serious side effects of smallpox vaccine include progressive vaccinia, postvaccinial central nervous system disease, and eczema vaccinatum. Some of these reactions can be treated with vaccinia immune globulin or cidofovir. Proper patient screening and site care are essential. Family physicians must learn to screen potential vaccinees for contraindications (e.g., immunodeficiency, immunosuppression, certain skin and eye diseases, pregnancy, lactation, allergy to the vaccine or its components, moderate or severe intercurrent illness) and to treat vaccine-associated adverse reactions.