By Andrea Nakano

SAN RAFAEL (KPIX) — There has been a recent increase in COVID cases according the California’s Department of Public Health. The surge has prompted speculation among health officials colder weather keeping people indoors and waning immunity to the vaccine maybe contributing factors.

Marin has an incredibly high vaccination rate but even that county has seen an increase in COVID cases, of late. It’s especially concerning considering this is the time of year that we saw a significant spike in 2020. COVID cases hovered around 3000 per day in the state last October but skyrocketed to more than 58,000 by December.

READ MORE: Bay Area Remembers 1941 Attack On Pearl Harbor That Changed America Forever

UCSF epidemiologist Dr. George Rutherford feels there is reason to be optimistic that the numbers won’t explode this year.

“The difference maker this winter is we have a lot of people vaccinated and the vaccines work really really well.” says Dr. Rutherford.

Marin County has led the way in the Bay Area with 81% of the total population vaccinated and just this weekend, held a pediatric super site at Miller Creek Middle School. In all, nearly 2400 kids between ages 5-11 got the shot.

READ MORE: 'Prolific' San Francisco Retail Theft Suspect Back In Jail After New Arrest

“I think it’s a normal seasonal swing. We’ll see cases go back up and there’s going to breakthrough infections because we all know vaccines are about 90% effective but the more of us that are vaccinated the fewer breakthrough infections we will see,” says Marin resident Ted Whitney.

Another resident, Marty O’Hagan adds, “I’m cautiously optimistic. I would say that we are better equipped than we were a year ago.”

Meanwhile, state health officials are urging people to get vaccinated in order to curb any sort of winter surge, and to get the booster. It’s estimated that less than half of those over 65 have received their booster shot.

MORE NEWS: Scott Peterson Returning To San Mateo County Courtroom Wednesday For Re-Sentencing

“One thing that bothers me is that there have been 2.7 million doses of booster vaccine that have been delivered but the population of California over 65 is 5.7 million,” says Dr. Rutherford.