Coronavirus can be transmitted by physical contact, saliva droplets, and inhalation of aerosols that can linger in the air for hours, even if the infected person has left the room. This transmission can be direct or indirect, from large droplets or small aerosols, coming from an infected person who is coughing, sneezing, breathing or talking.
Large droplets are sprayed into the air like tiny cannonballs and typically fall to the ground within seconds in a 2m/6ft radius. Airborne transmission through aerosols can occur over a large distance ranging from seconds to hours. Aerosols will linger in the air like smoke.
Aerosols with the virus enter the respiratory system through the nose and mouth. Virus particles are deposited along the respiratory pathway, and can reach the deeper tissues of the lungs. This is a significant mode of transmission for COVID-19.