Preliminary results from antibody tests in Los Angeles County indicate that the true number of COVID-19 infections is much higher than the number of confirmed cases there, which implies that the fatality rate is much lower than the official tallies suggest. "The mortality rate now has dropped a lot," Barbara Ferrer, director of the Los Angeles County Department of Public Health, said at a press briefing today. In contrast with the current crude case fatality rate of about 4.5 percent, she said, the study suggests that 0.1 percent to 0.2 percent of people infected by the virus will die, which would make COVID-19 only somewhat more deadly than the seasonal flu.

Based on a representative sample of 863 adults tested early this month, researchers at the University of Southern California (USC), working in collaboration with the public health department, found that "approximately 4.1% of the county's adult population has antibody to the virus." Taking into account the statistical margin of error, the results indicate that "2.8% to 5.6% of the county's adult population has antibody to the virus—which translates to approximately 221,000 to 442,000 adults in the county who have had the infection." That is 28 to 55 times higher than the tally of confirmed cases at the time of the study.

As of noon today, Los Angeles County had reported 617 deaths out of 13,816 confirmed cases, which implies a fatality rate of 4.5 percent. Based on that death toll, the new study suggests the true fatality rate among everyone infected by the virus is somewhere between 0.1 percent and 0.3 percent (without taking into account people infected since the study was conducted). The lower end of that range is about the same as the estimated fatality rate for the seasonal flu.

https://reason.com/2020/04/20/l-a-county-antibody-tests-suggest-the-fatality-rate-for-covid-19-is-much-lower-than-people-feared/