"Those three cases did not have a travel history. It wasn't like they just got off a plane from South Africa or somewhere else. Meaning that there must be unseen community spread of that virus that we are not yet detecting," said Dr. Joe DeRisi, professor of biochemistry and biophysics at UCSF and co-president of Chan Zuckerberg Biohub.
To avoid a winter surge, Dr. DeRisi is urging the public to get boosted this week before any holiday gatherings.
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"Large numbers of people are coming together in indoor spaces close together probably without masks. Omicron is really going to take advantage of this. This is the worst possible situation," said Dr. DeRisi.
The CDC projects the omicron variant could become the dominant strain in the coming weeks.
"I use to see 2-5 positives a day and now we are seeing over 30 positives a day which is an alarming rate that we hadn't seen in the past," said Salu Ribeiro, founder of testing company Bay PLS.
Ribiero is waiting for sequencing results to determine if any of the positive tests contain the omicron variant.
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If infected, symptoms can appear two days after exposure.
"We know there are confirmed cases elsewhere in the city. The uptick is now. Omicron is on the uptick and people need to protect themselves," said Dr. DeRisi.
COVID testing company Bay PLS is now seeing an increase in testing across the Bay Area.
"Get tested and get your booster before you go to a holiday party," said Ribiero.
RELATED: Fauci says omicron variant can evade vaccine protection, but COVID boosters help
The latest data shows the benefit of a booster shot against the omicron variant.
"A large number of papers have been coming out and the consensus in the scientific community both here and around the world, and together with our own work suggest that just two doses of the vaccine are insufficient to fully protect against omicron. However the booster restores much of that protection," said Dr. DeRisi.
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