@Bluetick - The sinks were not P-trapped. Yes, the commode is by its natural design, but they all were on the same vertical drain stack so when you flushed aerosolized shit got blown out the drains of the sinks on floors below yours. This was what made that situation unique and enabled me to analyze what happened, since there was no other plausible mechanism that people who did not know each other and were separated by several FLOORS had no other reasonable explanation for being able to infect each other, yet NOBODY ELSE in the building got infected -- just those on that same vertical drain stack.

@Mentalic - That doesn't help if the spike is directly pathogenic, and it appears that it is. As I've repeatedly noted we've never been able to successfully vaccinate against coronaviruses before and it's not because we haven't tried.

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