"This may be the start of a winter surge," said Dr. George Rutherford, UCSF Professor of Epidemiology.
Despite 61 percent of Californians being fully vaccinated, Dr. Rutherford says the winter months hold a significant risk as indoor gatherings increase for the holidays.
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The latest data is giving this expert a flashback of last November.
"We are seeing an increase. Cases are up about 20 percent of where they were two weeks ago. Hospitalizations are up about six percent. To me, that is worrisome but it can go right back down," said Dr. Rutherford.
Salu Ribeiro is the founder of "Bay PLS" a company focused on COVID testing and vaccinations across California's Bay Are. They began to notice an increase in positive COVID tests in the last two weeks.
"It's about two percent to three percent positivity rate. When was the last time you noticed an increase like this one? Similar to last year at the same time. We are seeing a trend. If you see the map of the COVID test from last year to this year," said Ribeiro.
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More vaccination, booster shots and an increase in testing could mitigate a winter surge.
"Now that we had Halloween and Dia de los Muertos and people were out and having a good time. It's important that you come back and get tested to make sure that you didn't get exposed and now are carrying the virus for somebody else," said Susana Rojas, Executive Director of the Latino Task Force.
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The hope is also that with 3.5 million Californians ages 5-11 years old able to get vaccinated a winter surge could also be prevented.
"While we may have a winter surge it may be much less than it was last year," said Dr. Rutherford.
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