Impact of COVID-19 Pandemic on the Influenza Vaccination and Predictors of Influenza Vaccination in Japan: A Cross-sectional Study

Abstract

Objective: With the current global pandemic of COVID-19, there is concern that an influenza outbreak could exacerbate the health care burden. Improving the influenza vaccination rate is becoming more critical because controlling the spread of influenza is essential for reducing excess mortality. Therefore, we investigated whether the influenza vaccination rate changed during the COVID-19 pandemic in Japan and identified the factors associated with influenza vaccination uptake. Design: This cross-sectional study used data from an Internet survey with adjustments to approximate a nationally representative estimate using inverse probability weighting. Setting: A total of 23 142 respondents, aged 15 to 80 years, were evaluated to estimate weighted percentages and prevalence ratios with 95% confidence intervals of influenza vaccination in the period 2020-2021. Results: Overall, in the period 2020-2021, the influenza vaccination rate rose from 38.1% before the COVID-19 pandemic to 44.6%. “Using traditional media” was a positive predictor of influenza vaccination uptake. “Using social media,” “COVID-19 vaccine hesitancy,” and “living in a prefecture with a high proportion of COVID-19 cases” were negative predictors. Conclusions: It is crucial to use predictors of influenza vaccination, such as how to use the media, for promoting a more widespread influenza vaccination uptake. The results of this study may be helpful in improving influenza vaccination rates, which could reduce the burden on health care services during outbreaks of influenza and COVID-19.