Corona Virus Guidelines from the CDC
The CDC has published a comprehensive website that covers many of the questions you have been asking about the corona virus.
https://www.cdc.gov/coronavirus/2019-ncov/index.html
The corona virus appears to be very easily to transmit. It spreads from person to person trhough physical contact with the victim or things the victim touched. It also spreads from respiratory droplets in the air or on surfaces. The corona virus can be contracted through infected surfaces such as doorknobs, elevator buttons, and any surfaces, especially those in public places such as trains, buses, restaurants, and rest rooms.
Much needs to be learned about the Corona Virus at this time.
COVID-19 is an emerging disease and there is more to learn about its transmissibility, severity, and other features and what will happen in the United States.