SAN MATEO COUNTY (CBS SF) – Calling the holidays a “super critical time,” San Mateo County’s health officer appealed to residents to stay vigilant and called out careless behavior as COVID-19 cases surge ahead of Thanksgiving.

Health officer Dr. Scott Morrow told residents in a statement posted Monday, “Right now, enough people are acting like they are individuals, carelessly, thoughtlessly, and I would add quite selfishly, whether by intent or not, resulting in a surge in new cases.”

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Morrow said due to such behavior, “everyone’s lives are disrupted, schools will not function properly, and your favorite businesses will close, likely forever.”

The county, which had made it to the Orange Tier in the state’s reopening plan was among those moved back into the Red Tier last week. San Mateo, along with San Francisco and Marin, are the only Bay Area counties not in the Purple Tier, which has the most COVID-19 restrictions.

According to county health data posted Wednesday, 2,317 new coronavirus cases in the county have been reported in the last 30 days. During the month of November, there have been eight days where 100 or more new cases have been reported in the county.

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As of Wednesday, 44 patients with COVID-19 are in county hospitals, with eight patients in the ICU.

“I know many of you would like me, or the government, or some external entity to provide some magical remedy to make it all better. It doesn’t work that way,” Morrow went on to say. “While there is an enormous infrastructure stood up to try to protect you, if you don’t pay attention to your own actions, you will not like what is to come and how it will impact the people you care about.”

The health officer has had tough words for residents flouting COVID-19 restrictions before. During the early days of the pandemic in March, he blasted people who disregarded the first round of shelter-in-place and social distancing orders by saying, “You spit in our face, and you will contribute to the death toll that will follow.”

This time around, Morrow ended his statement on a hopeful note, recalling that the county had a “manageable” case rate from early September through Halloween. “I know we can do it again. It’s in your hands,” he concluded.

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Since the start of the pandemic, at least 13,707 people have been infected and 170 people have died from COVID-19 in San Mateo County.