Louisiana is setting records for new COVID-19 diagnoses, and the state’s omicron variant surge is just beginning, Gov. John Bel Edwards said Thursday.

“A few days after New Year’s Day, K-through-12 schools are going to resume … while we are in a surge like we haven’t yet experienced,” he said.

Thursday’s 24-hour total of 12,467 new cases was more than a third above Wednesday’s 9,378, Edwards said during a news conference livestreamed on Zoom.

He said the U.S. Centers for Disease Control and Prevention said Wednesday’s figure was itself a state record, topping 7,548 set in August, during the delta variant surge.

The governor said he would not mandate masks unless such an order is needed to keep hospitals from being overwhelmed. But he said people should heed masking recommendations from both the CDC and the state Department of Health.

Wearing a mask is a minor inconvenience “compared to being in a hospital struggling to get oxygen or watching a loved one struggling to get oxygen,” he said.

Edwards noted that the new cases reported Thursday outstripped the four-day Christmas holiday total of 12,165. That earlier figure had been one “that really took my breath away,” he said.

Edwards says the number of people hospitalized with the virus has risen 268% since Dec. 17, to 762.

He and other state and hospital officials around south and central Louisiana repeatedly urged everyone to take precautions such as getting vaccinations and booster shots, wearing masks, washing hands, and staying 6 feet (2 meters) from people outside their immediate families.

The surge has upended his own holiday plans, he said, with relatives who had planned Christmas visits staying at their own homes. He’ll also watch this week’s football games on TV.

“A month ago I would have said I was going to be at both the Sugar Bowl and the Saints game. I will do neither,” he said.

Even though reports indicate that the omicron variant generally causes less serious illness than the delta variant, it makes so many people sick that hospitalization numbers go up fast, Edwards said.

“It’s just a factor of math.” he said.

The omicron variant spreads so quickly that it could cause outbreaks large enough to close schools if precautions aren’t taken, said Theresa Sokol, the state epidemiologist.

She said numerous school outbreaks have been traced to extracurricular activities or to meals, when students can’t wear masks, she said.

Students should wear masks and, if possible, sit at least 6 feet apart when eating, she said. She recommended a temporary halt to extracurricular activities and social gatherings such as pep rallies and dances.

“My son was in basketball camp over winter break. I pulled him out because I thought the risk was too great,” even though he’s fully vaccinated, she said.

If it’s possible, students and teachers should be tested before returning to school so infected people without symptoms don’t bring in the virus, Sokol said.

She said the state health department offers a free testing program for schools. Parents of children at schools that aren’t participating should suggest that their school join in, she said.