By Joe Barrett and Ben Kesling

States and major cities across the country have imposed the most extensive restrictions on business and social gatherings since widespread lockdowns during the spring, in hopes of preventing a further surge in Covid-19 cases over the winter holidays.

Even as Pfizer Inc. and Moderna Inc. deliver the first doses of the coronavirus vaccine, officials are pleading with a weary -- and sometimes defiant -- public to avoid the kinds of gatherings and travel that helped drive new cases to record levels nationally after Thanksgiving.

"We can't let up now. We need to continue all our efforts to stop the spread of Covid-19 in a very vulnerable time," said Dr. Rachel Levine, secretary of health in Pennsylvania, where Democratic Gov. Tom Wolf on Dec. 10 ordered places such as movie theaters and bowling alleys to close through Jan. 4, and limited restaurants to takeout service, prompting some to stay open in resistance.

Nearly 85 million Americans are expected to travel from Dec. 23 through Jan. 3, off at least 29% from last year, according to an estimate by AAA. In states across the country, small businesses and restaurants are being hit with de facto lockdowns because of occupancy limits or restrictions on dining. At the same time, big-box retailers have been permitted to stay open, in part because their large stores allow for social distancing, prompting resentment from small-business owners.

Brenda Reid, owner of Brenda's Family Restaurant in Mill Run, Pa., said she had no choice but to defy the state's shutdown of indoor dining, saying she and her eight employees rely on the income. Ms. Reid added that she drained most of her savings during the five-week spring shutdown.

If she closed now, Ms. Reid said, she probably would need to shut the restaurant permanently and find a new job. "At 68 years old, that's a little hard," she said.

In the spring, all but a handful of states issued stay-at-home orders that ground nonessential economic activity to a halt. At the time, states were short of ventilators, testing capacity and personal protective equipment for health-care workers, and lacked treatments for the new virus. Those broad orders slowed the rate of infection and bought time for hospitals to catch up. Now, as case numbers surge, most states are clamping down on activities that help the virus spread while trying to avoid a complete shutdown of the economy.

North Carolina, which currently has a curfew on nonessential activities, issued its initial stay-at-home order on March 27.

"We didn't know how fast the virus was spreading, what we were really dealing with," said Dr. Mandy Cohen, North Carolina's secretary of health and human services. "More importantly, we didn't have our response capabilities up and mature."

After the spring shutdowns, some states dropped many restrictions, while others eased back.

"We really use the dimmer-switch approach to try to keep the level of viral spread under control. And I think that really helped us as a state, " Dr. Cohen said.

As case counts and hospitalizations have risen this fall, the state has had to turn the dial back up. On Dec. 8, Dr. Cohen and Democratic Gov. Roy Cooper announced an order requiring people to stay inside between 10 p.m. and 5 a.m. through at least Jan. 8.

New Jersey and Virginia have also put in place stay-at-home orders from 10 p.m. to 5 a.m., while other states have closed restaurants and bars at 10 p.m.

New Mexico and California have stay-at-home orders that vary by region or county.

New Mexico, which unveiled a two-week stay-at-home order on Nov. 13, is now under a county-by-county order, depending on the latest data. In California, four of five regions face some of the tightest restrictions in the country, with indoor and outdoor dining halted and businesses such as wineries and hair salons shut for at least three weeks, after spare capacity in regional intensive-care units fell below 15%, under a plan Gov. Gavin Newsom, a Democrat, announced on Dec. 3.

In Wisconsin, efforts by the administration of Democratic Gov. Tony Evers to restrict businesses to help slow the virus suffered multiple setbacks in court.

"Our inability to mitigate issues around this disease has been very frustrating," Mr. Evers said last week.

Some states, such as North Dakota, have imposed fewer restrictions despite being hit hard by the pandemic. On Dec. 9, the state extended limits on bars and restaurants to 50% of capacity and forced early closing times, but allowed high-school sports to resume on Dec. 14.

"We're grateful because we know people love their high-school sports," said Gov. Doug Burgum, a Republican. On Monday, he allowed bars to resume normal business hours.

In Chicago, where bars and restaurants are closed for indoor service and people are asked to limit social gatherings to six individuals, officials monitor social media to break up potential superspreader events.

Chicago authorities said they work with Airbnb Inc. and Eventbrite Inc. to keep tabs on people renting party pads or selling tickets to illegal gatherings, and try to shut down parties before they start.

A spokeswoman for Eventbrite said Chicago officials have focused on the company's "Report This Event" feature, which allows users to flag questionable gatherings. A spokeswoman for Airbnb said the company has banned parties at rentals and won't allow one-night bookings over New Year's Eve. She added that Airbnb is working with local governments to crack down on people who violate local ordinances.

"Pandemic fatigue is real. People are tired of doing this," said Ivan Capifali, deputy commissioner of Chicago's Department of Business Affairs and Consumer Protection.

While many places experienced an increase in coronavirus cases after Thanksgiving, Minnesota credited a shutdown of indoor and outdoor services at restaurants and bars ahead of the holiday -- as well as other measures -- with reversing a surge in case numbers.

"I am incredibly grateful for the sacrifices you made to pull that back down. We've still got a ways to go," Democratic Gov. Tim Walz said on Dec. 16 as he rolled back some of those restrictions.

The state now allows outdoor dining again, but kept the ban on indoor dining, prompting more than 150 restaurant, bar and small-business owners to pledge resistance in a Facebook group called the ReOpen Minnesota Coalition.

The state attorney general has filed lawsuits against two bars that opened to large indoor crowds last week.

Trevor Holte, a 53-year-old auto broker, said he spent four hours at one of the two, Alibi Drinkery, a sports bar in Lakeville, Minn. "People are fed up with government overreach," he said.

Last Friday, the state secured a temporary restraining order against the bar opening for indoor service, but it remained open through Monday, according to Michael Padden, the bar's attorney. At a hearing Wednesday morning, Judge Jerome Abrams said he would render a decision as quickly as possible.

Write to Joe Barrett at joseph.barrett@wsj.com and Ben Kesling at benjamin.kesling@wsj.com

(END) Dow Jones Newswires

12-23-20 1229ET