Originally Posted by Excargodog

You “arguing” does not change reality and sensitivity per se is not the measure of merit for any lab test. The measure of merit is predictive value positive and predictive value negative, which is a function of sensitivity, specificity, and the actual rate of disease in the population being studied IAW Baye’s Theorem.

For the current PCR tests the measurement must be made during the time that virus is actually present which presents serious difficulties for detecting the MAJORITY of the infected who have few or no symptoms. Thus the predictive value of PCR testing for detecting WHETHER OR NOT THE INDIVIDUAL IS VIRGIN OR AT LEAST PARTIALLY IMMUNE, which from an epidemiological perspective of determining R0 which is pretty much the real question PCR is indeed a POS.

I will concede that if there’s a patient dying with ARDS in the ICU and you want to know whether the person is dying from coronavirus, influenza virus, parainfluenza virus, adenovirus, cytomegalovirus, or herpes simplex virus, a sensitive PCR test might actually be helpful. But for determining who out there is and is not likely to get coronavirus in the future, which is the decision before the government, it’s kind of worthless as tits on a boar hog.

and yeah, I know, even if antibodies are there they MAY not be protective and MAY not be long lasting, but USUALLY they are indeed at least to some extent and for some duration protective, all of which lowers the R0.