https://www.cdc.gov/coronavirus/2019-ncov/about/index.html https://www.cdc.gov/coronavirus/2019-ncov/downloads/2019-ncov-factsheet.pdf https://www.cdc.gov/coronavirus/2019-ncov/downloads/sick-with-2019-nCoV-fact-sheet.pdf https://socoemergency.org/emergency/coronavirus/