The coronavirus outbreak in Los Angeles County could be up to 55 times more widespread than previously thought with a much lower fatality rate, according to a new study.
The University of Southern California and the Los Angeles Department of Public Health released research Monday that found 4.1% of adults in the county had antibodies to the coronavirus and estimated between approximately 221,000 to 442,000 adults have already had the virus. The county, home to more than 10 million people, had confirmed just 13,816 cases as of Monday.
“We haven’t known the true extent of COVID-19 infections in our community because we have only tested people with symptoms, and the availability of tests has been limited,” said lead investigator Neeraj Sood, a USC professor of public policy. “The estimates also suggest that we might have to recalibrate disease prediction models and rethink public health strategies.”
The study tested 863 people from the county and has not yet been peer-reviewed. Researchers plan to continue testing residents every few weeks.
“These results indicate that many persons may have been unknowingly infected and at risk of transmitting the virus to others,” said Dr. Barbara Ferrer, director of the L.A. County Department of Public Health. “These findings underscore the importance of expanded polymerase chain reaction (PCR) testing to diagnose those with infection so they can be isolated and quarantined, while also maintaining the broad social distancing interventions.”
Because the number of infections could be higher than previously thought, the fatality rate may be much lower.
“Though the results indicate a lower risk of death among those with infection than was previously thought, the number of COVID-related deaths each day continues to mount, highlighting the need for continued vigorous prevention and control efforts,” said Paul Simon, chief science officer at the L.A. County Department of Public Health and co-lead on the study.
The research comes amid a call for increased antibody testing, including in New York, the U.S. epicenter of the virus. Gov. Andrew Cuomo announced Monday that thousands of New Yorkers will be randomly selected at grocery stores across the state to determine how many were infected by the virus and recovered.
“That will tell us, for the first time, what percent of the population actually has had the coronavirus and is now at least short-term immune to the virus,” he explained. “This will be the first, true snapshot of what we are really dealing with.”
