Background: The goal of the National Smallpox Vaccination Program was to vaccinate a cadre of healthcare workers and first responders who could care for smallpox patients in the event of an attack.
Methods: Using a convenience sample of health departments (n=49) and hospitals (n=60) in five states, we conducted a telephone interview between July 2003 and April 2004 of healthcare workers and first responders who chose not to receive smallpox vaccination. (Data were analyzed in 2004 and 2005.)
Results: The response rate was 63%. Of 1895 respondents, 723 (38.2%) reported having a contraindication, 280 (14.8%) reported being contraindicated because of a household member's condition, and 892 (47.0%) reported having no contraindication to smallpox vaccination. Among respondents with no contraindication, the leading reasons for nonvaccination were concerns about side effects (20.6%) and not feeling that the risk of outbreak was high enough (19.5%). More than half (54.8%) were somewhat or very concerned about having an adverse reaction to the vaccine; Hispanics, blacks, and Asians were significantly more likely than whites to be somewhat or very concerned about side effects. Less than one fifth (17.9%) reported that there was a policy to financially compensate employees who developed side effects from vaccination, and 40.7% reported that there was a policy to provide liability coverage to employees who transmitted vaccinia to a patient.
Conclusions: Many people who chose not to receive smallpox vaccine perceived their personal risk-benefit balance as not favoring vaccination. The success of future smallpox vaccination efforts or vaccination against other bioterrorist health threats depends on addressing potential barriers to participation including compensation and liability issues, in addition to clearly communicating risks and benefits.