COVID-19 vaccination did not improve employee mental health: A prospective study in an early phase of vaccination in Japan

The effect of the COVID-19 vaccination as an individual-based preventive measure on mental health is largely unclear in the literature. The authors report a preliminary finding on whether vaccination effectively improves mental health among employees in Japan based on a prospective study (E-COCO-J). Of the total sample (N=948), 105 (11.1%) were vaccinated at least once at the follow-up survey (June 2021). There was no significant effect of vaccination on the change of psychological distress at baseline (February 2021) and follow-up (June 2021), after adjusting for gender, age, marital status, education, chronic disease, company size, industry, and occupation (healthcare workers or non-HCWs). Providing continuous mental health care for employees is important in an early vaccination phase.