Here's how many omicron cases have been identified in California and the Bay Area - San Francisco Chronicle

With at least 30 cases of the highly mutated omicron variant now identified in the United States — including two new cases reported in Los Angeles County on Monday — health experts can’t yet say whether it will pose a bigger threat than the delta strain, which is still driving the national coronavirus pandemic.

So far six coronavirus cases have been identified as omicron in the Bay Area: one reported on Tuesday in San Francisco, which was the first in the U.S., and a cluster of five in Alameda County that were reported on Friday.

Alameda County officials characterized those five as being in an outbreak of 12 coronavirus cases, but have not yet said if the other seven were identified as omicron.

California has reported nine omicron cases in all, though public health officials said they expect to find many more in the coming weeks.

Charles Chiu, the UCSF scientist who led the team that identified the San Francisco omicron case, said Monday that his team is actively screening for such cases and working with some other Bay Area counties to do more “systematic surveillance for omicron” with other labs.

The county routinely sends a quarter of its samples for sequencing, and all in the past two months have been the delta variant, with no omicron detected, he said.

Federal health officials say early signs indicate omicron may cause less severe disease than the dominant delta variant, though much more study is needed.

The five cases that were sequenced and identified as omicron — with the infected individuals described as “mildly symptomatic” by public health officials — emerged from an outbreak of 12 coronavirus infection cases in people ranging in age from 18 to 49, according to a press release.

Health officials on Monday declined to answer further questions on the outbreak.

No additional omicron cases had been identified by the health department as of Monday.

Other than Alameda County and San Francisco, no other Bay Area counties have yet reported omicron cases and they continue to monitor for the variant.

Willis said the county’s overall coronavirus cases have “increased significantly over the past week” but the hospitalization rate continues to decrease, withno COVID patients in county hospitals on Sunday.

Contra Costa County officials said 97% of its sequenced samples reveal infections caused by the delta variant, and they are seeing a small uptick in cases but declining hospitalizations.

Santa Clara County’s health department, which reviews 20% to 40% of reported coronavirus cases — including by examining wastewater — also said Monday that no omicron has yet been found.