The first COVID-19 vaccinations in the United States and Europe began in 2020. In Japan, however, they started in 2021, much later than in the rest of the world. At that time, all kinds of information about the COVID-19 vaccine were flooding on social media, which may have influenced attitudes toward vaccination. This study aimed to investigate what kind of information about the COVID-19 vaccine had been obtained through Japanese social media. In April 2021, before vaccination was generally available in Japan, we conducted a web-based questionnaire survey among 71 Japanese working adults, with a broad sampling of residence, occupation, and age. Respondents were asked to freely describe the information they had learned about the COVID-19 vaccine through various media, including social media. A total of 181 key phrases were extracted from the descriptions and classified into 30 categories that included both positive and negative content. The co-occurrence network analysis revealed that the word "vaccination" tended to be frequently associated with the words “side-effect” and "death", and that the COVID-19 vaccine was frequently portrayed as something negative in Japan. In addition, the correspondence analysis indicated that, compared to others, social media have spread the personal experiences of vaccinated and the mismanagement of the vaccination by local governments. This study is the first to demonstrate that negative and specific examples of information about the COVID-19 vaccine tended to prevail on social media in Japan.
Sanae Inoue, University of Tsukuba, Japan
Kei Fuji, University of Tsukuba, Japan