Parental Vaccine Hesitancy and Risk of Pediatric Influenza Under-Vaccination in a Safety-Net Health Care System.

OBJECTIVE: To measure the risk of influenza under-vaccination in children of vaccine-hesitant parents, referent to children of nonhesitant parents, in a sample of disadvantaged families in one influenza season. STUDY DESIGN: A prospective observational cohort study of English- and Spanish-speaking parents of 2-year-olds presenting at random for well, sick, or specialty visit care from August 1, 2019 to February 28, 2020. Parents answered demographic questions and the Parent Attitudes about Childhood Vaccines survey. We followed children until season's end, extracting vaccination data on April 30, 2020. We dichotomized vaccination status as unvaccinated or partially/fully vaccinated, analyzing data with multivariable Poisson regression; in secondary analyses, we conducted adjusted time-to-event analyses. RESULTS: Overall, 263 parents consented (response rate: 90%); our final sample included 255 dyads. Thirty-three (13%) parents were vaccine hesitant. In adjusted analyses, children of hesitant parents (n = 33) had a 195% increased risk (adjusted Risk Ratio 2.95; 95% confidence interval 1.91, 4.56) of being unvaccinated at season's end, referent to children of nonhesitant parents (n = 222). In time-to-event analyses, children of vaccine-hesitant parents were also more likely to be unvaccinated before influenza activity peaked (P = .02). CONCLUSIONS: Parental vaccine hesitancy tripled the risk of pediatric influenza nonvaccination in a sample of poor and minority families during the 2019 to 2020 influenza season. As parental vaccine hesitancy appears to exacerbate pediatric influenza vaccination disparities, future work should explore parental hesitancy with poor and minority stakeholders and tailor evidence-based interventions to benefit children from these communities who receive care at all practice sites.