Omicron variant detected in Contra Costa County

Omicron variant detected in Contra Costa County
Dr. Chris Farnitano, health officer for Contra Costa County, speaks at a news conference on March 23, 2020.

The omicron variant of COVID-19 that is rapidly spreading worldwide has reached Contra Costa County, officials announced Monday.

“Genomic sequencing of positive COVID-19 test results from Contra Costa County has identified three cases with the omicron variant of the virus,” county officials said in a statement, adding, “None of the three people infected with Omicron had gotten a booster shot, although two were fully vaccinated. So far, no one has been hospitalized.”

County Health Officer Dr. Chris Farnitano said it was “a matter of time” before the highly contagious omicron variant appeared in Contra Costa. Omicron likely circulated in the community for several weeks, officials said, adding that genetic evidence of the variant was detected in a wastewater sample from central Contra Costa on Dec. 8. Still, the delta variant of COVID-19 remains the predominant strain in Contra Costa, “accounting for more than 97 percent of genetically sequenced COVID-19 samples collected in the county,” officials said.

Whether the variant is delta or omicron, public health experts are encouraging vaccinations for those who haven’t yet done so, and booster shots for eligible residents, to prevent serious illness. Anyone who is 16 or older and was previously vaccinated can get a booster dose once six months have passed since their last dose of Pfizer or Moderna vaccine, or two months have passed since they received a dose of the Johnson & Johnson (Janssen) vaccine. 

“We’ve been encouraging anyone who is eligible to get a booster dose of the Pfizer or Moderna vaccine to do so,” Farnitano said in a statement. “With today’s news and the holidays just around the corner, that message is even more important. People who get the booster are far less likely to get gravely ill or be hospitalized. That’s our wish for this holiday season.”

As of Monday, just over one-third of eligible Contra Costa residents had received a booster dose of the COVID-19 vaccine.

“The 7-day average number of daily new COVID-19 cases reported in the county has increased about 5 percent over the past two weeks, and the number of people hospitalized in Contra Costa because of the virus has remained stable so far this month,” officials said.

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