California public health officials approved San Mateo County's move from the most restrictive purple tier COVID-19 designation to the less-restrictive red tier on Feb. 23. It means that more businesses and activities in the county will be allowed. The new tier will go into effect at 12:01 a.m. on Wednesday, Feb. 24.

Five counties moved to a less restrictive tier on Tuesday: Humboldt, Marin, San Mateo, Shasta, and Yolo moved from purple to red. Trinity County worsened, going from orange to red. Forty-seven counties remain in the purple tier, nine in the red tier and two stayed in the orange tier, according to state data.

San Mateo County officials said the movement to the red tier and downward trend in infections are encouraging.

"This is great news for our small businesses and our entire community,” said San Mateo County Board of Supervisors President David J. Canepa. “And this move is a direct result of all of us taking personal responsibility for our actions. If we wear our damn masks, keep our distance and follow common-sense health and safety protocols, we can get back to doing what we all love to do.”

San Mateo County progressed to the red tier due to two metrics, calculated by the state: the case rate, which has dropped to 5.6% and the health equity quartile positivity rate, which is now down to 3.7 percent. The health equity quartile measures rates of infection with the virus in the county’s most disadvantaged communities based on the California Health Places Index.

Louise Rogers, San Mateo County Health System chief, told the Board of Supervisors on Tuesday that the county has among the lowest disparities percentage in the Bay Area. "We want to drive the disparity to zero," she said.

Under the red tier, churches, synagogues, mosques and other religious gatherings including weddings can take place indoors at no more than 25% capacity or 100 people, whichever is less; most retailers, including malls, can open indoors to up to 50% capacity and restaurants can reopen indoors to a maximum of 25% of capacity or 100 people. Dance studios, and gyms can reopen indoors at 10% capacity, and hair and nail salons can reopen indoors with modifications.

All schools can reopen fully for in-person instruction, but the decision is up to local or county officials, according to the state website. In San Mateo County, decisions on public school operations are made by local school boards in consultation with the San Mateo County Office of Education. Anyone interested in the potential impact on schools should contact local school districts, the county said in a press release.

Under the updated guidance for youth and recreational adult sports, outdoor high-contact and moderate-contact sport competitions may resume in the red tier and the purple tier, with modifications, including testing requirements for certain outdoor high-contact sports. The updated guidance takes effect on Feb. 26.

Large gatherings are still prohibited, which include festivals, but museums, zoos and movie theaters can reopen to 25% of capacity.

The four-tier system -- yellow, orange, red and purple -- has criteria for tightening or loosening activities based on the state of COVID-19 cases and infection positivity rates, according to the state'sBlueprint for a Safer Economy . Purple is indicated for counties where there is widespread risk of infection; red is substantial risk, orange moderate and yellow is minimal risk. As conditions improve, counties can progress to the less restrictive tiers.

Rogers said the county is also in a good position with testing and vaccinations. San Mateo County has performed 821 tests per 100,000 people, the second highest testing rate in the state, behind Yolo County, Rogers said. The county has vaccinated 130,514 people; 59.1% of people 65 and older and 66.4% of those who are 75 and older have been vaccinated, said Dr. Anand Chabra, medical director of the Family Health Services Division and lead for the county's vaccination efforts, told the supervisors.