The University of California, Los Angeles will reinstate an indoor mask policy as coronavirus cases surge in the nation’s most populous state.

The University of California, Los Angeles said on thursday it will reinstate an indoor mask policy as coronavirus cases surge in the nation’s most populous state.

There are few signs of COVID-19 precautions, but cases are on the rise, with about 19,000 new daily cases reported in California, according to the Centers for Disease Control and Prevention. Los Angeles County is moving closer to what the CDC categorizes as a high level of community transmission, a designation which would trigger the return of mask mandates. 

Universal indoor masking would be implemented across L.A. County," Dr. Barbara Ferrer, director of the L.A. County Public Health Department, said of the potential designation. 

In New York City, meanwhile, cases are up more than 17% from two weeks ago, according to the city's health department. 

The Omicron subvariant BA.5 — the fastest-spreading form of Omicron so far — is responsible for more than half of all new cases in the nation, according to the CDC. The subvariant appears to be three to four times more resistant to antibodies. 

Dr. Celine Gounder, editor-at-large of Kaiser Health News, warns that even if you were vaccinated early on or contracted COVID, you may not be fully protected against the subvariant. 

"Do not try to game this out. If you are eligible for a vaccine, don't wait," Gounder said. "There are early hints the BA.5 subvariant may be more virulent. So in other words, may cause more severe disease."

Boosters designed to target Omicron could be ready by the fall. But in L.A., if transmission levels remain high for the next couple of weeks, mask mandates could return by the end of the month.