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The director of the Centers for Disease Control and Prevention has given the final go-ahead for children ages 12 to 15 to get Pfizer's COVID-19 booster.

"It is critical that we protect our children and teens from COVID-19 infection and the complications of severe disease," CDC Director Rochelle Walensky said in a statement endorsing the CDC advisory panel's recommendation to expand booster eligibility.

The CDC recommends that adolescents between the ages of 12 and 17 get a Pfizer booster five months after their second dose.

-ABC News' Cheyenne Haslett

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