(1/5) Study of a possible case of #SARSCoV2 transmission involving faecal aerosols in an apartment building. Families in vertically aligned flats on the 25th and 27th floors may have been infected by aerosols produced by toilet flushing on the 15th floor.
acpjournals.org/doi/10.7326/M2…
acpjournals.org/doi/10.7326/M2…
(2/5) Dried-out floor and/or bath drains are hypothesised to have enabled aerosols to enter the apartments via the vertical drainage stack linking them. This is supported by an environmental sample from an empty flat on floor 16 testing positive.
(3/5) During the follow-up investigation, tracer gas released in the toilet on floor 15 was able to reach multiple apartments, including the apartments on the 25th and 27th floor in which the hypothesised secondary cases lived.
(4/5) While contact between the 3 families cannot be ruled out, none was known to have occurred. The index family (on floor 15) usually wore masks when using the apartment lift, and no viral RNA was detected on lift buttons or the lift air supply inlet.
(5/5) The authors recommend ensuring that drainage traps (including floor drains) are not allowed to dry out. They also note the importance of ventilation in bathrooms, given that toilet flushing can generate faecal aerosols which may be inhaled or could contaminate surfaces.
