A device, foreground left, measures whether air ventilation is sufficient at an okonomiyaki restaurant in the Osaka Prefecture city of Sakai, on Feb. 26, 2021. (Mainichi/Hitoshi Sonobe)

       The Mainichi Shimbun answers some common questions readers may have about aerosol transmission of the coronavirus.

       Question: I've heard people talking about aerosol transmission of the coronavirus. What is that?

       Answer: Aerosols are fine particles suspended in the air. Virus particles emitted from people's mouths and noses when they cough or sneeze, among other actions, become included in aerosols; they can travel long distances on air currents, and sometimes remain in the air for a long time. Aerosol transmission of a virus is when people breathe those particles in.

       Q: How is this different to airborne infection?

       A: Aerosol transmission essentially means transmission through aerosols, and includes airborne infection. The airborne transmission people commonly think of is how highly infectious diseases like measles and tuberculosis spread. At first, the coronavirus was not that transmissible, so some experts probably thought airborne transmission was not possible. But now some experts say it is just as infectious, if not more, than measles and other such diseases.

       Q: How can people get infected?

       A: Coming into close contact with an infected person presents danger of transmission, but aerosols can float in the air for a long time and over a wide area, so in situations where ventilation is poor or people are singing or exercising, infection is possible even when the person carrying the virus is over 2 meters away. When a person remains in a poorly ventilated, closed space for 15 minutes or longer, they reportedly risk infection even when simply passing through a space an infected person has just left.

       Q: That's scary. What can we do to prevent infection?

       A: There's no need for disproportionate fear. It's important to frequently ventilate areas and avoid crowded places. Use a nonwoven mask, and wear it without gaps between the mask and your face, and try not to remain in the same space for a long time.

       (Answers by Naomi Hayashi, Lifestyle and Medical News Department)

       Font Size S M L Print Timeline 0