The risk of contagion is highest in indoor spaces but can be reduced by applying all available measures to combat infection via aerosols. Here is an overview of the likelihood of infection in three everyday scenarios, based on the safety measures used and the length of exposure
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In the spring, health authorities failed to focus on aerosol transmission, but recent scientific publications have forced the World Health Organization (WHO) and the CDC to acknowledge it. An article in the prestigious Science magazine found that there is "overwhelming evidence" that airborne transmission is a "major transmission route" for the coronavirus, and the CDC now notes that, "under certain conditions, they seem to have infected others who were more than six feet [two meters] away. These transmissions occurred within enclosed spaces that had inadequate ventilation. Sometimes the infected person was breathing heavily, for example, while singing or exercising."