Reasons for and against receiving influenza vaccination in a working age population in Japan: a national cross-sectional study

Background: To improve influenza vaccination coverage in the working age population, it is necessary to understand the current status and awareness of influenza vaccination. This study aimed to determine influenza vaccination coverage in Japan and reasons for receiving the vaccine or not. Methods: An anonymous internet-based survey was performed in September 2011. Our target study size was 3,000 participants between 20 and 69 years of age, with approximately 300 men and 300 women in each of five age groups (20-29, 30-39, 40-49, 50-59, and 60-69). We asked the history of influenza vaccine uptake in the previous year, and reasons for having vaccination or not. Results: There were 3,129 respondents, of whom 24.2% of males and 27.6% of females received influenza vaccination between October 2010 and March 2011. Among those who were vaccinated, the main reasons for receiving the influenza vaccine were "Wanted to avoid becoming infected with influenza virus" (males: 84.0%; females: 82.6%) and "Even if infected with influenza, wanted to prevent the symptoms from becoming serious" (males: 60.7%; females: 66.4%). Among those not vaccinated, the most frequent reasons for not receiving the influenza vaccine included "No time to visit a medical institution" (males: 32.0%; females: 22.4%) and "Unlikely to become infected with influenza" (males: 25.1%; females: 22.7%). Conclusions: The reasons for receiving the influenza vaccine varied between age groups and between sexes. To heighten awareness of influenza vaccination among unvaccinated working age participants, different intervention approaches according to sex and age group may be necessary.