How it Spreads

COVID-19 is spread by the respiratory droplets an infected person produces when they breathe, cough, sneeze, talk, or sing. If you are in contact with an infected person, the virus can enter your body if droplets get into your throat, nose, or eyes.

Last updated: August 24, 2021

COVID-19 Transmission

Respiratory infections such as influenza (flu) and COVID-19 are mainly spread by liquid droplets that come out of the mouth and nose when a person with the virus breathes, coughs, sneezes, talks, or sings.

Getting immunized, staying home when sick, visiting others outdoors or in small groups, wearing masks in indoor public spaces, increasing ventilation, and cleaning your hands are all important measures that will reduce transmission.

Droplet Sizes

Most COVID-19 infections are spread from one person to another through respiratory droplets.

Droplets come in a wide range of sizes and they behave differently depending on their size. Larger droplets are heavier, and they usually fall to the ground within two meters. Smaller droplets, also known as aerosols, are lighter and they can float in the air for longer.

Smaller droplets can collect in enclosed spaces when there is not enough fresh air. Indoor accumulation is greater when more people share a space, spend more time together, or exercise, sing, shout, or speak loudly. These conditions can lead to COVID-19 transmission. Opening windows or increasing fresh air intake with mechanical ventilation are important protective measures that can help reduce the spread of COVID-19.

Surface Contact

Even though COVID-19 can survive for hours or days on different surfaces, infection from contact with contaminated surfaces appears to be rare. The most common type of spread is through contact with the respiratory droplets of an infected person.

Ways You Can Reduce Transmission

Get immunized with a COVID-19 vaccine. You are considered fully immunized seven days after your second dose.
Stay home if you are sick.
Visit with people outside of your immediate household outdoors or in smal groups.
Avoid crowded areas.
Wear a well-fitted 3-layer mask that covers your nose and mouth and goes under your chin in indoor public spaces.

All people 12 and older are required to wear a mask in indoor public spaces regardless of their vaccination status. Read about the PHO order on masks in public indoor settings.

Bring fresh air indoors by opening windows and doors, or using mechanical ventilation.
Wash your hands often with soap and water for at least 20 seconds, or use an alcohol-based hand sanitizer containing at least 60% alcohol.
Cough and sneeze into the bend of your arm or a tissue, discard tissues safely, and clean your hands after.
Avoid touching your face with unclean hands.
Clean and disinfect surfaces and objects that are frequently touched by many people.

Provincial Health Services Authority

How it Spreads

COVID-19 Transmission

Droplet Sizes

Surface Contact

Ways You Can Reduce Transmission

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