We have struggled with vaccine hesitancy for vaccination rollout during the COVID-19 pandemic. Although the spread of misinformation seems to play a role in vaccine hesitancy, the extent to which it affects attitudes toward COVID-19 vaccination is unknown. Here, we investigated the prevalence of beliefs about misinformation regarding COVID-19 vaccines in vaccinated and unvaccinated populations in Japan and analyzed associated risk factors. An online survey of 31,000 participants in 2021 found that 8.1% of vaccine-accepted individuals believed vaccine-related misinformation, whereas 36.6% of those who refused vaccination believed misinformation. Most factors associated with beliefs about misinformation and vaccine hesitancy overlapped, including young age, unmarried status, low income, particular information sources, and history of COVID-19 infection. Interestingly, some factors, such as age and sources of information, had different effects on vaccine acceptance between individuals who did not believe misinformation and those who did. Advanced age was associated with vaccine acceptance among non-misinformation believers. In contrast, misinformation believers in their 10s and 20s were more willing to be vaccinated than older adults. The effects of television and Internet information were stronger in individuals who believed misinformation on their attitude toward vaccination than non-misinformation believers. This study highlights the importance of understanding the relationship between beliefs about misinformation and vaccine hesitancy for ongoing and future pandemics.

The authors have declared no competing interest.

This work was supported by the Strategic Center of Biomedical Advanced Vaccine Research and Development for Preparedness and Response (JP243fa627001 and JP243fa627004) from the Japan Agency for Medical Research and Development; by the Grant-in-Aid for Scientific Research (JP16KK0059, JP18H03107, JP19K10446, JP19KK0204, JP21H04856, and JP23K09693) from the Japan Society for the Promotion of Science; by the Health Labour Sciences Research Grants (19FA1012) from the Ministry of Health, Labour and Welfare; by the Innovative Research Program on Suicide Countermeasures (R3-2-2) from the Japan Suicide Countermeasures Promotion Center; by the Grants from Chiba Foundation for Health Promotion & Disease Prevention (grant number not available); and by the Nagasaki University State of the Art Research program from Nagasaki University (grant number not available). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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IRB of the Osaka International Cancer Institute gave ethical approval for this work.

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