I'm thinking that 85/21,750 or 0.4% of the controls developed the disease (vs 0.04% of those who received vaccine). It does seem low for the US where you have

I'm thinking that 85/21,750 or 0.4% of the controls developed the disease (vs 0.04% of those who received vaccine). It does seem low for the US where you have 3% of the population had disease already in 2020. Perhaps more data came from Germany? Or it could be they measure not just PCR +ve results, but antibody levels and/or severe symptoms?