People are starting to talk about "testing everybody" for COVID as an elimination strategy. I've got bad news for those people, I'm afraid.

As far as I know, we have never "tested everybody" for any disease in human history. Mongolia is trying with hep B and hep C, but it's going to take them a decade.

COVID infection only lasts a few weeks, so that's the timescale within which you'd need to "test everybody". Otherwise people you tested first could catch it while you were busy testing others the following month.

National TB prevalence surveys have sample sizes in the tens of thousands. They take years to plan and usually a full year to execute. They majorly clog up national labs testing a fraction of a percent of the population for TB.

"Testing everybody" for COVID at once is about as realistic as removing everybody's appendix at once. We can't even sell everybody a packet of toilet paper at once, and we have a lot more supermarkets than laboratories.