SAN JOSE (CBS SF) — Santa Clara County health officials made an urgent plea for residents to receive their COVID-19 vaccine boosters Thursday, as cases of the rapidly spreading omicron variant are rising.

Dr. Sara Cody, the county’s public health director, made a dire prediction about the weeks ahead as the variant spreads and cases rise.

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“When I look around the corner ahead, what I see is a deluge of omicron. What I see is perhaps one of the most challenging moments we have yet in the pandemic,” Cody said at a news conference Thursday. “And I think it’s challenging because it’s not what we’re expecting. We’ve all come to learn to live with COVID over the last two years and we’re all a little bit tired.”

Cody said there are now 10 cases of the variant, one week after confirming the county’s first case. The variant has also been found in all four wastewater treatment plants in the county, while it was found only in one treatment plant a week ago.

Among the cases, four were unvaccinated people. Five of the cases were among those who were vaccinated but did not receive their booster shot, while the remaining case had the third dose but did not reach full immunity.

Cody also predicted the variant, first discovered about a month ago, would take hold in the United States just as it has in Europe. While the county boasts a high vaccination rate, Cody urged booster shots as other highly-vaccinated communities abroad are also dealing with rapidly rising cases.

“Norway and Denmark, for example, are highly vaccinated just as we are here in Santa Clara County, and they both have seen explosive growth of omicron,” she said.

“All of America should be concerned,” said Stanford University Hospital epidemiologist Dr. Jorge Salinas.

He said that vaccines are no longer enough, and instead layers of protection must be considered when gathering over the holidays, including boosters, masks, testing and gathering in small groups while in ventilated areas.

“Unless we make those modifications and potentially put off travel, if at all possible, January is going to look very bad for all of America,” Dr. Salinas said. “The holidays will make the January wave worse. What we need to do is modify our behaviors over the next two to three weeks.”

Officials in Santa Clara County said only 44% of eligible residents have yet to receive the booster shot, which includes 250,000 residents age 50 and over.

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Dr. Marty Fenstersheib, the county’s testing officer, said “Two shots are not enough anymore,” referring to the two-shot regimen for the Pfizer and Moderna vaccines. “Before we worry about going younger, let’s get those 250,000 adults boosted so that we can keep them from getting hospitalized or dying.”

Along with booster shots, officials urged other tips to slow the spread including the wearing of masks indoors, particularly in crowded settings.

“I just want to make sure that everyone in our community understands what’s ahead and what’s around the corner because there are things we can do now,” Cody said. “We now have a variant that all evidence suggests grows really fast and takes over really fast.”

Looking at trends in Europe, which have foreshadowed what may take place in the U.S., she said there are examples of highly-vaccinated countries struggling to handle the omicron variant. Cody added that omicron has now been detected in all four sewer sheds across the county. She worries that one of the most transmissible mutations of the COVID-19 virus will spread easily as people relax their personal response to the pandemic after almost two years.

“I think it’s really important for everyone to get vaccinated. If everyone gets it, hopefully we can get back to normal,” said Ben Reveno, a south San Jose resident getting his booster shot at the Santa Clara County fairgrounds on Thursday. “I know many people affected by this and, actually, both of my roommates just got it; (I) thought it was best to get it before the other vaccines wear off.”

Cody explained that omicron requires protection levels to go up and the booster is the only way to maintain full immunity after six months. She stopped short of calling on the initial series and the booster dose together becoming the new standard definition for “fully vaccinated” in the county. Cody added that testing and masking remain crucial. She also emphasized ventilation and distancing as necessary steps and she pointed out the need to wear a mask outdoors at the news conference because so many people were together.

“This is about layers of prevention. No single strategy works. We have to combine them,” she said. “To be fully up-to-date, you need to have a booster.”

For the second holiday in a row, Deborah Leibovitch said she and her family plan to spend it away from family and friends because of the threat of the omicron variant.

“We’re afraid to do something,” Leibovitch said. “Sad that we can’t move on and there is no quick fix. We really have to buckle down.”

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