Previously, the agency said COVID-19 is spread “most often” by touching a contaminated surface or having close contact with an infected person who transmits the virus through droplets created when they speak, cough, sneeze or otherwise throw themselves out of their mouth.
These droplets were believed to fall to the ground very quickly. The new guidelines say it can take “seconds or minutes” and the infection can also be transmitted through aerosols – smaller droplets that “persist in the air under certain circumstances.”
According to the new guidelines, droplets and aerosols can infect a person by being inhaled or coming into contact with the mouth, nose or eyes.
Contact with contaminated surfaces, followed by contact with the face without washing hands first, remains within the guide as another potential method of transmission.
Canada’s chief public health officer referred to the new directions Tuesday during a press conference with Prime Minister Justin Trudeau and other cabinet members.
“This is why we have advised Canadians to try to avoid the three Cs – closed spaces with [poor] ventilation, crowded places with large numbers of people gathered together and close contact situations where you can’t maintain physical distance, ”said Dr Theresa Tam.
“This pandemic teaches us a lot about flexibility and adaptation to new challenges. ”
Canada’s new wording on aerosols is very similar to that of the World Health Organization, which recognized aerosol transmission for the first time in July.
The United States Centers for Disease Control released similar guidelines in October, although they stressed at the time that they still believed that prolonged and close contact with an infected person was a much greater source of spread of COVID-19.