> An analysis of the blood of some 3,300 people living in Santa Clara county found that, by early April, one in every 66 people had been infected with SARS-CoV-

> An analysis of the blood of some 3,300 people living in Santa Clara county found that, by early April, one in every 66 people had been infected with SARS-CoV-2 So it's 1.5% then, according to this study. With effect size so small one has to look at the test's accuracy. This one lists 20% false negative and 0% false positive, however the sample size for the test's evaluation was in low dozens. According to the article evaluating a test properly requires a sample size of hundreds. So we don't know with any certainty how good this test is because it was not sufficiently evaluated. If the false positive rate is over 1.5% the results would become invalid. For a sense of scale consider that the Bodysphere antibody test has 9% false positive rate, and some other tests are at 4.5%.