The California Department of Public Health, or CDPH, announced Monday a statewide mask mandate effective Dec. 15 through Jan. 15.

The mandate, which requires masks to be worn indoors in public spaces regardless of vaccination status, comes in response to a 47% increase in the seven-day average COVID-19 case rate across the state since Thanksgiving, as well as a 14% increase in hospitalizations, according to the CDPH.

Stefan Elgstrand, spokesperson for Berkeley Mayor Jesse Arreguín, said the statewide mandate takes the place of local health orders in regard to masks.

The CDPH said the mandate also comes in response to the omicron variant — labeled by the World Health Organization as a “variant of concern” — that has been detected in California.

Elgstrand said it is expected for cases to rise during the winter months. However, the rise of the “highly contagious” omicron variant is concerning enough to warrant the mandate, he added.

The CDPH statement cited California hospitals being at or above capacity as further reasoning to implement the measures.

“Even a moderate surge in cases and hospitalizations could materially impact California’s health care delivery system,” the statement reads.

Furthermore, in a science brief by the Centers for Disease Control and Prevention, at least 10 studies have shown that universal masking results in infection rates “significantly” falling. The CDPH added that multiple U.S. surveys suggest that an increase of 10% in self-reported mask-wearing increased the likelihood of slowing community transmission rates threefold.

“We know people are tired and hungry for normalcy. Frankly, I am too,” said Dr. Mark Ghaly, California Health and Human Services secretary, according to CalMatters. “We are proactively putting this tool of universal indoor masking in public settings in place to ensure we get through a time of joy and hope without a darker cloud of concern and despair.”

The CDPH is also continuing to encourage Californians to get vaccinated. About 80% of Californians have received at least one dose of the COVID-19 vaccine, and as of Dec. 10, booster vaccinations have expanded availability to eligible individuals ages 16 to 17, according to the CDPH.

Elgstrand added that research shows that the omicron variant is able to easily infect those who are fully vaccinated. However, he noted that getting a booster shot provides protection against infection.

“In addition to following the mask protocols and getting tested before and after traveling, the best thing people can do to protect themselves against omicron is to get a booster shot,” Elgstrand said.