https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-changes-simplify-use-bivalent-mrna-covid-19-vaccines "Coronavirus (COVID-19) Update: FDA Authorizes Changes to Simplify Use of Bivalent mRNA COVID-19 Vaccines" https://ja.wikipedia.org/wiki/%E3%82%AA%E3%83%BC%E3%83%89%E3%83%AA%E3%83%BC%E3%83%BB%E3%83%98%E3%83%97%E3%83%90%E3%83%BC%E3%83%B3