The U.S. Centers for Disease Control and Prevention announced Monday afternoon it will shorten the recommended isolation time for some people infected with COVID-19.

Patients who are asymptomatic will have to isolate for five days, followed by five days of wearing a mask around others, under the new guidance. Previously, the isolation period was 10 days for everyone.

Individuals who have received their booster shot do not need to quarantine following an exposure, but should wear a mask for 10 days after the exposure, the CDC said.

"The Omicron variant is spreading quickly and has the potential to impact all facets of our society. CDC’s updated recommendations for isolation and quarantine balance what we know about the spread of the virus and the protection provided by vaccination and booster doses," CDC Director Dr. Rochelle Walensky said in a statement.

The Texas Department of State Health Services announced Monday that centers in Austin, El Paso, Fort Worth, San Antonio and The Woodlands ran out of sotrovimab, the monoclonal antibody effective against the COVID-19 omicron variant.

The federal government won't be able to ship more supplies of the treatment until January, the department said.

Those centers will still be able to provide monoclonal treatment for any patient who hasn't contracted the omicron variant, according to the department.

French Prime Minister Jean Castex and Health Minister Olivier Véran announced a host of new measures Monday to combat the rising COVID-19 cases.

The country has recorded 30,383 cases in the last 24 hours, according to officials.

Starting Jan. 3, all companies will be required to have their employees work from home at least three days a week, when possible.

France will also limit large indoor gatherings 2,000 people and outdoor gatherings to 5,000.

Officials also announced a ban on eating and drinking in movie theaters and on public transportation. The new measures will be in effect for at least three weeks, officials said.

-ABC News' Ibtissem Guenfoud

Pediatric hospitalizations for COVID-19 in the U.S. are surging to their highest levels since early September.

Across the country, almost 2,000 children are hospitalized with confirmed or suspected cases of the virus, according to federal data.

This is a roughly 60% from one month ago.

On average, about 260 children are being admitted to the hospital each day.

On a state level, more children are hospitalized with COVID-19 in New York than in any other state in the U.S.

-ABC News' Arielle Mitropoulos

The newly updated CDC guidelines don't require testing at the end of isolation because PCR tests can stay positive for up to 12 weeks, CDC Director Dr. Rochelle Walensky told "Good Morning America" Wednesday.

"So we would have people in isolation for a very long time if we were relying on PCRs," Walensky said.

Walensky also addressed Tuesday's news from the FDA that, according to early data, rapid antigen tests may be less sensitive when it comes to the omicron variant.

"We do know that the most sensitive test you can do is a PCR test," Walensky said. "So if you have symptoms and you have a negative antigen test, we do ask you to go and get a PCR to make sure those symptoms are not attributable to COVID."

Walensky said rapid tests do work "quite well," especially in places where people are being tested regularly, like at schools.

"They may not work as well as they have for the delta variant," Walensky said, but "we still are encouraging their use."