Santa Clara County reported its first case of the COVID-19 omicron variant, health officials confirmed Friday.
The individual was fully vaccinated but had not received a booster shot, county officials said. The patient had recently returned from domestic travel out of state and is now in isolation. They had experienced mild symptoms and recovered quickly before entering quarantine, officials said.
The variant already had been reported elsewhere in the Bay Area and in California, though the state has reported just 14 cases so far.
Public Health Director Dr. Sara Cody and other Santa Clara County officials discussed the anticipated arrival of the omicron variant and reinforced the importance of booster shots during a news conference Friday morning.
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"Although there are still many unknowns about this variant, we strongly recommend getting vaccinated and getting your booster if you haven’t already to help guard against Omicron," Cody said in a statement. "It is a new variant, but we know what to do, and that’s to continue with all our layers of protection: vaccinate, boost, mask, ventilate, distance, and test often."
The Centers for Disease Control and Prevention on Thursday gave the green light to Pfizer's booster shot for youths ages 16-17, and Santa Clara County began administering the shot for that age group almost immediately.
Cody said COVID-19 cases among the unvaccinated are shooting "straight up," and were at 80 per 100,000 residents as of Friday. Cases among the vaccinated also were rising but not nearly as fast.
Dr. Marty Fenstersheib, the county's vaccine officer, said about 80% of eligible residents have been fully vaccinated, without the booster, but added that he and his colleagues have found those initial doses aren't quite enough to stave off infection, especially with new variants surfacing.
"We want people to know they really need the booster," he said.
About 39% of those eligible for the booster in the county have received one. In the 18- to 49-year-old demographic, that number drops to 20%. Minority communities are of even greater concern.
"We still have some disparities, and when we look at the numbers, the vaccination rates of children who live on east side and in the south county are, in some cases, half of what they are in other areas of the community," Fenstersheib said.
The county also advised people to continue masking, testing, ventilation and distancing as those measures remain the best defenses against COVID-19, especially with a winter-holiday surge looming.