THIS IS HOW ALL DISEASES ARE TREATED
You can’t test every person, for everything.
ONLY symptomatic people usually present themselves for care.
It is nearly impossible to tell how many people had a virus that never made them sick.
That is why the death rate for any disease is usually calculated as (number dead)/(number with symptoms)
(that’s divided by)
Re: “It is nearly impossible to tell how many people had a virus that never made them sick.”
After 73.5 million COVID tests in the USA, I am thinking it should be quite simple to calculate the number of asymptomatic infections - especially since the PCR test still detects COVID RNA months after it has become inactive.
My local Blood Donation Center is testing for COVID antibodies, too.