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How it Spreads

The coronavirus that causes COVID-19 is spread by liquid droplets when a person coughs, sneezes or sometimes talks or sings. If you are in close contact with an infected person, the virus can enter the body if droplets get into the eyes, nose or throat.
Last updated: July 30 at 3:45 PM

Respiratory diseases, like influenza and COVID-19, are spread by liquid droplets that come out of the mouth and nose when a person coughs, sneezes, and sometimes, when a person talks or sings. These droplets usually land one to two metres away, but they can land on another person if they are close by. Diseases can spread if droplets with the virus enter the body through the eyes, nose or throat.  

COVID-19 can also spread by touch. If droplets are left on objects and surfaces after an infected person sneezes, coughs on, or touches them, other people may become infected by touching these objects or surfaces, and then touching their eyes, nose or mouth. That’s why we recommend you cough or sneeze into your arm and wash your hands regularly.

Experiences of COVID-19 in hospital settings around the world, including in B.C., suggest that COVID-19 is primarily spread by droplet contact. While there is some discussion that COVID-19 can spread by staying in the air (by aerosols), there is no convincing scientific evidence to support this. An exception is aerosols produced by aerosol-generating medical procedures. 

Efforts to stop the spread of COVID-19 should focus on reducing droplet contact. 
  • Keep practising physical distancing
  • Stay home if you are sick and limit your contact with others
  • Wash your hands often with soap and water or an  alcohol-based hand sanitizer containing at least 60% alcohol
  • Cough and sneeze into a tissue or the bend of your arm
  • Avoid touching your face with unwashed hands
  • Clean and disinfect surfaces and objects
  • Wear a mask or face covering when needed 
Listen to Dr. Eleni Galanis answer this question (video).

Droplet contact versus airborne transmission

Droplet Contact 
  • Some diseases are spread by infected droplets contacting surfaces of the eye, nose, or mouth. Large droplets that may or may not be visible to the naked eye are made when a person sneezes or coughs. These droplets usually spread only one to two metres and quickly fall to the ground.
  • Influenza and SARS are examples of diseases that can spread by droplet contact. 
  • The evidence suggests that COVID-19 is transmitted by droplets. 
Airborne transmission
  • Airborne transmission is when microorganisms travel on much smaller evaporated droplets (often called aerosols). These droplets stay in the air for many hours and, often travel long distances. Transmission occurs when others breathe the microorganism into their throat or lungs.  
  • Examples of diseases spread by airborne transmission include measles, chickenpox and tuberculosis.  
SOURCE: How it Spreads ( )
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