I try to be sensitive to your obsessive repulsive disorder but the post didn't extrapolate anything it just reported the report's results along with a Google translation of the summary:
"The minimum overall seroprevalence of 5.5% suggests that on April 17, 2020, approximately 27,000 people were exposed to SARS-CoV-2 in the canton of Geneva."
...
"These first data show a seroprevalence in the population estimated at 3.5% (possible variability from 1.6% to 5.4%) for the first week and 5.5% (possible variability from 3.3% to 7, 7%) for the second."
If you want to guess at some unbounded number or extrapolate into the future without knowing what control measures were put in place that's fine, but that has nothing to do with the original post.
I doubt anyone else cares but on the off chance anyone wants to decipher deeb's babble here's the original link:
https://translate.google.com/transla...on&prev=search