Since vaccine efficacy is waning fast, most people in the US are actually unprotected unless they have recently boostered or are one of the ~150M Americans that have natural immunity.
From the large Swedish population study published in The Lancet (preprint), we know that Vaccine Efficacy (VE) against symptomatic infection wanes fast!
We can use this information, to calculate how man of the fully vaccinated in Germany are currently actually protected.
Vaccination was spread out from 12/2020 until now.
We know that VE reaches zero at month 8.