Possible airborne transmission of SARS-CoV-2 in apartment buildings

The International Journal of Infectious Diseases has a new preprint study (archived PDF here) that discovered something fascinating: SARS can travel in buildings, vertically, via ventilation ducts.

After a series of infections, all 437 residents of an apt building were tested. 10 infections uncovered, all living on different floors but along two vertical lines with openings through their bathrooms.

Ventilation shaft is located along each vertical line where shafts connect to units through blowhole in bathrooms. Units built before installation of exhaust fans w/backdraft dampers became compulsory. Thus, there's no physical block for air entering the room from the air duct.

Our study also implies that the rigid rules of safe distancing that stick to droplet and contact transmission based on an outdated dichotomous notion of respiratory droplet or aerosols should be reconsidered.