Association between elementary and middle school children with mixed/foreign parents and influenza vaccination in Japan.

Background: The number of children with foreign parents is increasing in Japan; however, the percentage of these children receiving the recommended annual influenza vaccination, which must be paid for voluntarily, may be quite low. Socioeconomic status may influence voluntary vaccination decisions. This study explored the association between elementary and middle school children with mixed (either of the parents was non-Japanese) /foreign parents (both parents were non-Japanese) and influenza vaccination in Japan, stratified by household income and maternal education.

Methods: We used combined data from eight cities in the Greater Tokyo area for the period from 2016 to 2019, which included 16,368 elementary and middle school students and their caregivers. Caregivers responded to questions about whether their children received influenza vaccination in the previous year and their foreign-born status. Multilevel Poisson regression was applied and further stratified by income status and maternal education.

Results: Three hundred ninety-one children (2.4%) had mixed parents, and 91 (0.6%) had foreign parents. When compared with Japanese children, children with mixed (incidence risk ratio, IRR: 0.80, confidence Interval, CI: 0.71, 0.90) and foreign parents (IRR: 0.70, CI: 0.56, 0.88) were less likely to receive influenza vaccination. After stratification, children with mixed/foreign parents were less likely to receive influenza vaccination than Japanese children only in households with high income and maternal education.

Conclusions: Children with mixed and foreign parents, especially in households with high socioeconomic status, had lower influenza vaccine coverage than Japanese children.