Professor of Pediatrics University of Colorado School of Medicine Aurora, Colorado, United States
Background: Many have suggested that the COVID-19 pandemic has had a long-term, negative impact on parental attitudes toward routine childhood vaccines. However, few data sources were systematically tracking vaccine hesitancy prior to the onset of the pandemic. In a previous analysis, we found significantly fewer parents with negative attitudes toward routine childhood vaccines immediately post-pandemic; this effect, however, disappeared by December 2020. Objective: To describe the impact of the COVID-19 pandemic on parental attitudes toward routine childhood vaccines through late 2021. Design/Methods: As part of a large study among 24 pediatric clinics in Colorado and Washington, we collected data from English- and Spanish-speaking parents of infants beginning in September 2019. At enrollment, parents completed the short form of the Parental Attitudes about Childhood Vaccines survey (PACV-SF), a validated survey scored from 0 to 4, with higher scores representing more negative attitudes. The exposure variable was onset of the COVID-19 pandemic in the United States in March 2020, with the before-period defined as 9/27/2019- 2/28/2020 and the after-period defined as 4/1/2020-9/30/2021. The outcome variable was parents’ negative attitudes toward childhood vaccines, defined as a score of ≥2 on the PACV-SF. Since an assumption of our natural experiment was that the probability of parents holding negative attitudes about childhood vaccines would have remained unchanged had the pandemic not occurred, we also used a secondary outcome variable not expected to change with the pandemic. This variable was the proportion of parents agreeing with a non-vaccine-related survey item (“It is important to introduce a feeding schedule for my baby as early as possible”). We estimated the probability of the outcomes after (versus before) the pandemic using log-binomial regression with generalized estimating equations adjusted for clinic-level clustering. Results: Among 8,594 parents, 12.5% were identified as having negative attitudes in the before-period versus 10.5% in the after-period. There were significantly reduced odds that parents had negative attitudes after (vs. before) the pandemic (Adjusted Odds Ratio [aOR] 0.82, 95% confidence interval [CI] 0.73-0.92, p< 0.001). There was no change in the feeding schedule variable (aOR, 1.02, 95% CI, 0.98-1.06).
Conclusion(s): In this natural experiment, we found that the odds a parent had negative attitudes toward childhood vaccines was less after (vs. before) the onset of the COVID-19 pandemic. Future work should continue to monitor vaccine confidence in the US and abroad.
