If you're talking about CDC's data tracker, which does report that 35mm figure (https://covid.cdc.gov/covid-data-tracker/#cases_casesper100klast7days https://co

If you're talking about CDC's data tracker, which does report that 35mm figure (https://covid.cdc.gov/covid-data-tracker/#cases_casesper100klast7days https://covid.cdc.gov/covid-data-tracker/#cases_casesper100k...), then this is misleading. 35mm cases have been confirmed using tests. Considering the vast majority of those who become infected with covid fail to display any symptoms whatsoever and are thus unlikely to be tested, this is very much a lower bound. Luckily, CDC has some estimates about how many people have actually been infected at this point: https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burden.html https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd... They estimate ~120mm Americans have been infected with coronavirus at this point. Considering we know that those with prior infection have durable, robust immunity (https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(21)00203-2 https://www.cell.com/cell-reports-medicine/fulltext/S2666-37...), that means roughly 1/3rd of Americans, regardless of vaccination status, are immune to covid. Of course, there's plenty of overlap between those vaccinated and those with natural immunity, so you can't just sum the numbers, but with ~70% vaccinated, we have to be approaching some kind of herd immunity level at this point.