In Japan, active recommendation of the human papillomavirus vaccine was withheld between 2013 and 2021 due to adverse reaction reports. This resulted in low vaccine coverage with reports from less than 1%. This study aimed to investigate if knowledge and health-belief related factors associated with vaccine intention among young adolescents with the hope that our findings may be helpful in promotion campaigns. We recruited students in four colleges and universities in Akita Prefecture from 2020 to 2021 who had never been vaccinated. A total of 318 students (male 54%, mean age 21 years) responded to a self-administered questionnaire; only 6% reported immediate vaccine intention, and 61% reported no such intention or "do not know." The correct percentages of 20-item knowledge about HPV vaccine-related morbidity, mortality, and prevention were very low regardless of gender (average males 41.4% vs. females 39.6%). Multivariable logistic regression models demonstrated that in males, higher levels of literacy, perceived susceptibility, and place for vaccination (logistical barrier) were associated with HPV vaccine intention, whereas "no need now" was associated with less intention. In females, a higher level of knowledge was significantly associated with vaccine intention, whereas "concerns of adverse effects" were associated with less intention.
Keywords: HPV vaccines; Japan; Vaccine intention; active recommendation; university students; vaccine acceptability.