A broad range of health effects in a cohort of 601 health care personnel, immunized with anthrax vaccine adsorbed (AVA) as a military occupational health requirement, were assessed to evaluate adverse events both qualitatively and quantitatively. Active surveillance showed that localized reactions were common and occurred more often in women than men. Five patients were reported to the Vaccine Adverse Event Reporting System, but only one event could be definitively attributed to immunization, a large localized reaction. Two separate cohort studies, one using nested data from a standardized health risk appraisal instrument and the other comparing rates of outpatient visits and hospitalizations, did not reveal significant differences between AVA-immunized and unimmunized individuals. Our findings suggest that AVA is relatively reactogenic but do not indicate serious adverse health effects due to immunization.