COVID-19 cases have been reported on every cruise ship operating in U.S. waters with passengers, according to the U.S. Centers for Disease Control and Prevention.

More than 90 ships are currently being investigated by the CDC or have been investigated and are still being observed by the agency.

In order to meet the threshold for a CDC investigation, a ship must report COVID-19 cases in more than 0.10% of passengers or have a single crew member test positive in the previous seven days.

The only ships in U.S. waters that have not met this criteria, according to the CDC, only have crew members on board.

-ABC News' Mina Kaji

The Los Angeles County Department of Health updated its COVID-19 safety measures Wednesday and mandated that all of the county's businesses must provide N95 or KN95 masks to employees who work indoors.

"Well-fitting medical grade masks, and surgical masks," are also acceptable under the order.

"Everyone needs to be sensible about how to protect themselves and those they love by layering on protections whenever around non-household members," LA County's health director, Dr. Barbara Ferrer, said in a statement. "At work, this means upgrading your mask if you work indoors and you are in contact with other workers or members of the public."

The Centers for Disease Control and Prevention advisory panel voted Wednesday to approve COVID-19 boosters for 12- to 15-year-olds.

CDC Director Rochelle Walensky will likely to sign off on the move later Wednesday night.

MORE: CDC panel recommends Pfizer boosters for 12-15 year olds, final call expected from CDC director

Shots could go into arms as soon as Thursday morning. The Food and Drug Administration authorized the Pfizer boosters on Monday, paving the way for the CDC’s final green light.

-ABC News' Cheyenne Haslett

The 2022 Grammy Awards have been postponed due to the surge in COVID-19 cases linked to the omicron variant.

"After careful consideration and analysis with city and state officials, health and safety experts, the artist community and our many partners, thx have postponed the 64th Annual GRAMMY Awards Show," CBS and the Recording Academy said in a joint statement.

The statement continued, "The health and safety of those in our music community, the live audience, and the hundreds of people who work tirelessly to produce our show remains our top priority.  Given the uncertainty surrounding the Omicron variant, holding the show on January 31 simply contains too many risks."

A future date for the Grammys has yet to be announced.

The awards show was scheduled to be held at the Arena in Los Angeles and hosted by "The Daily Show's" Trevor Noah.

This is the second year in a row that the Grammys has been postponed. Last year, the show was held in March after its original date was canceled in January.

Chicago Public Schools canceled its Wednesday classes after the Chicago Teachers Union voted against in-person learning amid a wave of COVID-19 cases.

All classes, both in-person and virtual, and all after-school activities have been cancelled.

"I understand your frustration and deeply regret this interruption to your child's learning," said Pedro Martinez, chief executive of the schools. "We want out children back in their classrooms as soon as possible and will continue working with the CTU to reach an agreement that addressed their concerns and that is in the best interest of all in our CPS community, especially our children."  

About 88% of the union's leadership and 73% of members voted on Tuesday to return to remote education, the union said in a statement.  

"To the parents and guardians of this city, we want you to know that when you put your children in our care we put their well-being and safety first," the union said in a statement. "We fight for your children like they are our own, because they are. As this pandemic continues, we will do everything in our power to ensure that our classrooms are the safest and healthiest places for your children to learn, thrive and grow."

Teachers were being locked out of their Google Classrooms, the union said on Twitter.