This chart is from an organization that does a good job of data analysis. This is their latest estimate by state of the total number of infected persons, detected and undetected. If the Minnesota number, 42%, is right, that is around three times the number of cases reported in the state. Note that Wisconsin’s rate is pretty similar. Of notice, the northern coast states have pretty low rates. Something seasonal I think. At this point, in some ways the higher the percent the better, as it indicates people with some level of adaptive immune response.
While we don’t know the overlap between those infected and those vaccinated, we do know that there are a lot of cases among groups that can’t get vaccinated. I suspect the non-overlap combination of vaccination and infection in Minnesota has to be around 70% to 80%, which really should impact transmission significantly, especially if you stop using over-sensitive PCR tests.