My reply is for can the coronavirus spread through pipes? Maybe it was spread in the entry way of the apartment building, maybe the person infected had just entered the building. & coughed. & sneezed as they walked to the stairs or elevator then the person that caught it walked in to the entry way. & breathed in the basteria, or maybe they used the same elevator or stairs. I would think that would be more apt to have happened their paths crossed some how as the infected person coughed &/or sneezed.