“… 2 , 20 , 22 , 24 , 26 , 28 , 30 , 32 , 33 , 35 , 37 , 52 , 53 , 54 , 55 , 56 Few of these studies have examined for viable virus, but for those that had, positivity was determined, although for few samples. 25 , 30 , 33 , 53 , 55 Concerns continue to be raised for the distance in which aerosol or airborne transmission can otherwise occur. 2 , 28 , 30 , 32 , 33 , 35 , 54 There are also possible contributions for heating, ventilation, and air conditioning units.…”