There may be many more coronavirus infections in Los Angeles than previously reported, and a lower fatality rate among them, according to an ongoing study jointly conducted by the University of Southern California and the Los Angeles County Department of Public Health.

Preliminary results of the study, according to a press release published Monday, revealed an estimate that was 28 to 55 times higher than the 7,994 confirmed cases of coronavirus in Los Angeles County as of early April. The study found that the real number of cases is somewhere between 221,000 to 442,000.

The study utilized antibody tests, which detect past infections of the virus, on a representative sample of adults across the county. The research is ongoing, and more rounds of testing will be conducted.

Because more infections were discovered than previously estimated, it is likely that the mortality rate is also lower. According to the press release, the current number of confirmed COVID-related deaths in the county is around 600.

"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 at USC Price School for Public Policy, in a press release about the study.

"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 Dr. Paul Simon, chief science officer at L.A. County Department of Public Health, in the press release.

Read the full press release.