Potential motivators affecting parental intention in COVID-19 vaccination for children aged 6 months to 4 years: Implications for targeted vaccine interventions in Japan

Although COVID-19 vaccination was approved for younger children in Japan in October 2022, uptake rates remain critically low. This study aimed to investigate Japanese parents' intentions, hesitators' probability of positive intention change, and factors that motivate COVID-19 vaccination. Parents with a 6-month to 4-year-old child living in Japan participated in this internet-based, cross-sectional survey conducted from December 19, 2022, to January 4, 2023. The modified Poisson regression analysis was used to assess the probabilities of changing intention by each motivator when comparing the degree of hesitancy among hesitators, and the Poisson generalized estimating equations were used to compare the probabilities of changing intentions by potential motivators within hesitant individuals. Among 12,502 participants, 10,008 (80.1%) were hesitators. Parents with lower hesitancy levels were more likely to be motivated to vaccinate their children through potential motivators. Vaccine hesitators were motivated to vaccinate their children, particularly by proven vaccine effectiveness (including protecting children from getting sick with a probability ratio [PR] of 3.7 [95% confidence interval (CI) 3.5-3.9] and less likely to infect adults with a PR of 2.9 [95% CI 2.8-3.1]), as well as vaccine safety (including safe vaccination of millions of children with a PR of 3.1 [95% CI 3.0-3.3]) compared to injunctive norm (including community leader recommendation). Therefore, initially addressing parents with low hesitancy levels is an effective strategy that motivates COVID-19 vaccination. Also, providing evidence-based information about COVID-19 vaccine efficacy and safety that is consistent with parents' needs is crucial.

Automated summary

Although COVID-19 vaccination was approved for younger children in Japan, the uptake rates remain low. Vaccine hesitators are more likely to be motivated by the proven effectiveness and safety of the vaccine. Therefore, addressing parents with lower hesitancy levels and providing evidence-based information is crucial in motivating COVID-19 vaccination.