CONTRA COSTA COUNTY (CBS SF) – Citing concerns about the omicron variant, Contra Costa County officials are requiring first responders and employees at homeless shelters to receive a COVID-19 vaccine booster or to undergo weekly testing.

The order, which takes effect on January 10, applies to law enforcement, firefighters, emergency medical personnel who work in or may respond to calls at “high-risk facilities,” such as hospitals, jails, nursing or congregate care facilities. Homeless shelter employees are also covered by the requirement, along with non-emergency ambulance workers who transport patients at the above facilities.

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Workers who have not received a booster shot by the deadline must undergo weekly PCR or antigen testing.

Contra Costa County’s new booster requirement comes amid a surge in COVID-19 cases, believed to be driven by the rapidly spreading variant. Health officials said the average daily number of newly detected cases in the county has risen about 156% in the past week, to 313 new cases per day.

The first cases of the variant in the county were confirmed by health officials just a week ago.

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Meanwhile, many county residents have yet to receive their boosters, with only 36% of people age 16 and older receiving the third shot.

“The omicron variant is much more infectious than previous strains of COVID-19,” health officer Dr. Chris Farnitano said in a statement on Monday. “Boosting is necessary for the best protection from omicron infection and transmission. Our hospitals are at risk of being overwhelmed if a large number of our must vulnerable residents get sick.”

Last week, the state required all healthcare workers, home care workers and employees of congregate care and detention facilities to receive their booster shots.

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More information about the booster shots and upcoming vaccination clinics can be found by visiting the Contra Costa Health Services website or by calling 1-833-829-2626.