In the USA the current daily rate of confirmed new cases is about 43000, not 55000. However there are a large number of "dark matter" cases not counted in official statistics. About 40% of infections are asymptomatic, and many more are paucisymptomatic. Most of those patients never get tested.
Most countries are rather waiting for a vaccine to become available and try to minimize the number of sick and dead in the meantime without interfering with economy too much.
(54.4k was number of newly confirmed cases on friday 10/2 by the John-Hopkins University btw. I'm aware that the US has inadequate testing [0] and that the real number is going to be a lot higher than this.
[0] https://ourworldindata.org/coronavirus-testing#the-positive-... )
It will continue to circulate in the population, just in a less explosive manner. This also means it is possible we will never reach herd immunity in some absolute sense much like we haven't for other coronaviruses.
My house has a fantastic filter along with a UV system as well. When I bought the house I thought it was overkill, but now I’m quite happy it’s there.
Ventilating properly requires discipline though. No tilted/semi-opened windows for prolonged time for example. In winter, heating should be turned off and the windows should be as wide open as possible to minimize the time to exchange air. That's to reduce the loss of heat. 5-10 minutes of ventilating is good enough, usually. We usually don't have air condition here, so I don't know what's the recommended process in the summer.
It's common to ventilate like this in Germany in the winter for example. I know (now returned) former German expats that completely missed this development. They still tilt windows and let the heating run all day long.
(That's why in Silicon Valley large companies have "air consultants" measure the freshness twice per year and report the rate. I've talked to some.)
So my question stands on how and what to do to have more effective air circulation indoors, and what else we should do. And why is this conversation only happening several months into a lockdown. It's as if American government is falling down from learned helplessness.
(Regarding herd immunity: you're aware that at the current rate of 55000 people per day, it would take 10 years to infect 60% of 320 million people? Nothing to say of the countless casualties that you would get in the process.)