This is potentially big news:
An estimated 320,000 adults in Los Angeles County may have been infected with coronavirus (vs ~8,000 testing positive), according to preliminary results of a study that suggests the illness is far more widespread than current testing shows and the death rate is much lower.
The study conducted April 10-11 by the county and the University of Southern California estimated that approximately 4.1% of the county’s adult population of 8 million has antibodies to the virus. When adjusted for margin of error, the infection rate ranged from 2.8% to 5.6%, or about 220,000 to 440,000 adults.
The study follows other research that has suggested more people have had coronavirus without symptoms — or without feeling ill enough to seek a test.
https://news.usc.edu/168987/antibody-testing-results-covid-19-infections-los-angeles-county/
If this is the case, the mortality rate is much lower.