Health care environments have been the setting for a number of pertussis outbreaks. Health care workers are at risk for occupational infections with pertussis and at risk for inadvertently transmitting pertussis to vulnerable patients, particularly the very young. An acellular pertussis vaccine (Tdap) was approved in 2005 by the US Food and Drug Administration for adults and adolescents, and recommendations from the US Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) call for its administration to the general population and, as soon as feasible, to health care personnel who work in hospitals or ambulatory care settings and have direct patient contact. ACOEM continues its support of that recommendation based on current knowledge of the epidemiology of pertussis, its transmission characteristics, documented risk in patient care settings, and efficacy of the Tdap vaccine.