Excellent question! The distinction here is between droplets and aerosol transmission. As I understand it, droplets are relatively large chunks of water (or wh

Excellent question! The distinction here is between droplets and aerosol transmission. As I understand it, droplets are relatively large chunks of water (or whatever), and aerosols are particles in suspension in a gas. At the beginning of the pandemic, most scientific professionals assumed that COVID-19 was transmitted by droplets; the 6 foot distancing advice comes from that assumption, since droplets don't have much range. (Which is not to say that increasing distance didn't help, but 6' wasn't a magic number.) This article goes into useful depth on our new understanding: https://www.science.org/doi/10.1126/science.abd9149?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed https://www.science.org/doi/10.1126/science.abd9149?url_ver=...