2468. Impact of a Herd Immunity Educational Intervention on Parental Concern About Measles

BACKGROUND: Maintaining high coverage of measles, mumps, and rubella (MMR) vaccination is important for preventing outbreaks and maintaining herd immunity (HI), which benefits both individuals and communities. We aimed to determine whether information about the benefits of HI and local MMR vaccination rates could change a parent’s concern about their child’s risk of contracting measles. METHODS: We conducted a survey at the 2016 Minnesota State Fair among Minnesota residents ≥18 years who had at least one child aged 6–18 years. Participants were asked to choose the correct definition of HI, to estimate the MMR vaccination coverage in their county, and guess the minimum MMR vaccination coverage needed to prevent measles outbreaks. We delivered an educational intervention through the interactive survey informing participants about the benefits of herd immunity, the actual MMR coverage in their county, and that ≥95% coverage is needed to prevent outbreaks. Before and after the educational intervention, participants were asked to report their level of concern about their child contracting measles. We calculated adjusted predicted percentages from logistic regression models to evaluate changes in concern about risk pre- and post-intervention and to assess factors associated with concern about measles. RESULTS: Among the 493 participants, 92.7% reported vaccinating their child with MMR, though one third were not familiar with HI. Prior to receiving information, those knowledgeable about HI were significantly more likely to be concerned about their child getting measles (predicted percentage 80.2% [95% CI: 75.7–84.6]) than those who were unfamiliar with HI (predicted percentage 69.8% [95% CI: 62.1–77.5]), P-value for the difference = 0.027. Participants believed that MMR vaccination was, on average, 9.0% [95% CI: 6.9–11.0] lower than the actual coverage in their local area. CONCLUSION: Information about HI and local vaccination coverage rates did not impact parental concern about their child being at risk for getting measles. Overall, parents learned that local MMR vaccination rates were higher than they had expected. DISCLOSURES: All authors: No reported disclosures.