LOS ANGELES (AP) — Firefighters in Silicon Valley were sent out to enforce statewide business restrictions as the state faced a Thanksgiving shadowed by an out-of-control coronavirus surge and health officials begged people to avoid large family gatherings that could become “superspreader” events.

“You have a 15-person gathering at a dinner table, then 1 in 10 of those tables could have ... a person that is unknowingly infecting others,” said Dr. Christina Ghaly, health services director in Los Angeles County, which has seen about a third of all COVID-19 cases in California and 40% of the deaths.

Ghaly said 1 in 145 people in the county is now infectious to others and the rate of spread could double every two weeks.

The county has passed a threshold that could see it implement a stricter and more sweeping stay-at-home order for residents soon, although not as sweeping as a March lockdown.

As with many other states, cases of COVID-19 have been skyrocketing for weeks in California. A record 18,350 were reported Tuesday, surpassing the previous daily high of more than 15,000 cases announced Saturday.

The seven-day average of positive tests has gone from 5.3% to 6.5% in the past week. The 14-day average has gone from 4.8% to 5.9%.

The fear is that the continuing COVID-19 surge could overwhelm the health care system. The state’s top public health officer has estimated that 12% of those who test positive for the virus could wind up in the hospital.

The toll could rise next month because it usually takes two to three weeks before people become ill enough to need hospitalization, health officials say.

As of Wednesday night, California instituted a nighttime curfew that bans nonessential work and gatherings for most of the state. LA County went even further. As of Wednesday night, restaurants must close for three weeks except for takeout, delivery and pickup. The rule aims to keep people indoors instead of eating and especially drinking at bars, wineries and restaurants.

The Los Angeles Area Chamber of Commerce said the restrictions could throw some 700,000 restaurant employees out of work.

“These measures will be devastating to families as well as businesses so close to the holidays, and without relief in sight,” an association statement said.

“I’m definitely scared,” Jaime Taylor, a server at Spago in West Hollywood, told KCBS-TV. “I’m by myself. I live alone. Spago was my main bread and butter. … It means a lot of uncertainty, a lot of questioning.”

Black Friday sales that typically draw enormous crowds also are in the spotlight. The holiday season leading into Christmas can account for a large chunk of store profits.

But stores must follow COVID-19 safety orders such as requiring employees and customers to wear masks and observe social distancing, health officers warned.

“Businesses have a legal, ethical, and moral obligation to protect their employees and the public,” said Michael Balliet, director of Community and Business Engagement for the County of Santa Clara.

Compliance officers were to fan out throughout the county starting Thursday and at least through Sunday to make sure businesses follow capacity rules and other precautions.

Firefighters who normally enforce capacity will help check businesses to make sure they are complying and call enforcement officials who will issue health fines on the spot starting at $250 and going into the thousands of dollars to those flouting the rules. There will no longer be a grace period for business owners to get by with a warning, Balliet said.

“We’re now at a point where it is vital that we ensure accountability at every level,” Balliet said.