1. Organization. WH. Coronavirus disease (COVID-19): How is it transmitted? 2021. Accessed September 1, 2023. who.int/news-room/q-a-detail/coronavirus-disease-covid-19-how-is-it-transmitted.
2. Prevention. CfDCa. Scientific brief: SARS-CoV-2 transmission 2021. www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/sars-cov-2-transmission.html Accessed September 1, 2023.
3. Diseases. NIoI. Route of transmission of SARS-CoV-2 2022. Accessed September 1, 2023. https://www.niid.go.jp/niid/ja/2019-ncov/2484-idsc/11053-covid19–78.html.
4. Ministry of Health LaW. About the SARS-CoV-2 Vaccine 2023. Accessed September 1, 2023. https://www.mhlw.go.jp/stf/seisakunitsuite/bunya/vaccine_00184.html.
5. Covid-19 breakthrough infections in vaccinated health care workers;Bergwerk;N Engl J Med,2021