The coronavirus spreads mainly from person to person. A person infected with coronavirus — even one with no symptoms — may emit aerosols when they talk or breathe. Aerosols are infectious viral particles that can float or drift around in the air for up to three hours. Another person can breathe in these aerosols and become infected with the coronavirus.
This can happen between people who are in close contact with one another. Droplets that are produced when an infected person coughs or sneezes may land in the mouths or noses of people who are nearby, or possibly be inhaled into their lungs.
Transmission is less likely to happen outdoors, where air currents scatter and dilute the virus, than in a home, office, or other confined space with limited air circulation.
The risk of spread from contact with contaminated surfaces or objects is considered to be extremely low. According to the CDC, each contact with a contaminated surface has less than a 1 in 10,000 chance of causing an infection.
The virus may be shed in saliva, semen, and feces; whether it is shed in vaginal fluids isn't known. Kissing can transmit the virus. Transmission of the virus through feces, or during vaginal or anal intercourse or oral sex, appears to be extremely unlikely at this time.