According to the Los Angeles County Department of Public Health, there were 37,215 new positive COVID cases, shattering the previous record of 27,091 set last Friday.
The county also reported 30 more COVID-related deaths on Thursday.
Meanwhile, state figures showed there were 2,661 COVID-positive patients in county hospitals as of Thursday, up from 2,461 on Wednesday. The number of those patients being treated in intensive care units was 352 on Thursday, up from 330 a day earlier.
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The number of COVID-positive patients hasn't been that high since mid-February of 2021. But the number is still well shy of the peak of more than 8,000 reached last January, at the height of that winter's surge in virus infections.
As demand for tests continue, L.A. County placed its at-home testing program on pause.
The county had been shipping free test kits to residents showing COVID-19 symptoms or to those who had been exposed to the virus. But the county put a temporary halt to the program Thursday as it tries to deal with a huge backlog in processing the kits.
"The Department of Health Services that runs that program is rapidly switching to making those in-home test kits available at the county's testing sites," said county Public Health Director Barbara Ferrer.
"Folks can either go to those sites and wait to get a test right there or they can go ahead and pick up one of those kits," Ferrer added.
Ferrer said efforts are being made to expand the number of COVID testing sites.
City News Service contributed to this report.