2020 年 57 巻 10 号 p. 526-529
Aerosol infection issues by COVID-19 were discussed from the viewpoint of particle technology, and the following conclusions were obtained: 1) Number of virus contained in a 10 μm droplet is very few, only 1 virus per 2000 droplets, whereas 0.5 virus in a 100 μm droplet, if 106 copies/mL of viral load in saliva is assumed. 2) Droplets larger than 100 μm can quickly settle down by gravity. 3) The possibility of aerosol infection is very low unless in unusual environments. 4) Mask is very effective, but the leakage from the space between mask and face has risk in heavy exhalation.
