How long did it take from purim when it is assumed the major spread happened in our community till total disaster? Less than 2 weeks. The incubation period is 2-14 days probably an average of 5-6 days. If there was going to be this terrible second wave you should be seeing trouble pretty soon.
That comparison is completely irrelevant, but total disaster was about 2 weeks after Purim. People realized it was super serious 3-5 days after. You have to consider that if the major spread was Purim, the virus was in the community at least the week before, which would account for the hospitalizations that woke everyone up the following week.
Purim is irrelevant, though, because it was an absolute worst case scenario. Even in our communities, you don't find another scenario that allows for a spread of that magnitude. Additionally, there are precautions being taken now, with crowd limits, PPE, social distancing awareness, and high-risk people self-isolating. The spread will definitely take longer and be less explosive than what we experienced in March, when virtually no precautions being taken by anyone.