RESUMEN
Parental concerns about vaccine safety have grown in the United States and abroad, resulting in delayed or skipped immunizations (often called "vaccine hesitancy"). To address vaccine hesitancy in Washington State, a public-private partnership of health organizations implemented and evaluated a 3-year community intervention, called the "Immunity Community." The intervention mobilized parents who value immunization and provided them with tools to engage in positive dialogue about immunizations in their communities. The evaluation used qualitative and quantitative methods, including focus groups, interviews, and pre and post online surveys of parents, to assess perceptions about and reactions to the intervention, assess facilitators and barriers to success, and track outcomes including parental knowledge and attitudes. The program successfully engaged parent volunteers to be immunization advocates. Surveys of parents in the intervention communities showed statistically significant improvements in vaccine-related attitudes: The percentage concerned about other parents not vaccinating their children increased from 81.2% to 88.6%, and the percentage reporting themselves as "vaccine-hesitant" decreased from 22.6% to 14.0%. There were not statistically significant changes in parental behaviors. This study demonstrates the promise of using parent advocates as part of a community-based approach to reduce vaccine hesitancy.