Royal Caribbean Group will soon require crew to be vaccinated for COVID-19 before returning to work.

In an email to crew members on Feb. 10 obtained by the Miami Herald, Royal Caribbean Group said the company is still working out the details of how to vaccinate its ship-board workforce but expects it will soon be a requirement. The website Crew Center first reported the announcement.

“The process may be different depending on where you live, the timing of your next contract, and whether you are already onboard or traveling,” the email to crew members said.

Crew members on cruise ships continue to suffer from COVID-19. Though cruises in the U.S. and much of the world are canceled indefinitely, small crews remain on board hundreds of cruise ships waiting for the go-ahead from regulators to welcome passengers again. According to a Miami Herald investigation, at least 1,779 crew members have contracted the virus, and at least 29 have died from COVID-19.

As the COVID-19 vaccine rolls out around the world, more and more countries are considering requiring a vaccine certificate for entry. British cruise line Saga Cruises and U.S.-based American Queen Steamboat Company and Victory Cruise Lines have announced they will require proof of vaccination for all guests and crew.

A spokesperson for Norwegian Cruise Line Holdings said the company is, “exploring all options regarding vaccinations for guests and crew and it is our intention that all crew members be vaccinated before boarding our vessels to begin their duties, subject to availability of the vaccine.” Spokespeople for MSC Cruises and Carnival Corporation said the companies haven’t yet decided on whether to require the vaccine for crew.

Cruises in the U.S. are banned indefinitely as cruise companies work to comply with the U.S. Centers for Disease Control and Prevention conditional sail order, which will eventually include mock cruises. The CDC has not yet published requirements for crew vaccination.

“CDC understands that vaccines and vaccinations will play a role in the resumption of passenger operations,” said agency spokesperson Caitlin Shockey in an email. “Additional details about the role of vaccines and vaccinations will be provided in future technical instructions and/or orders.”

Royal Caribbean Group also said it plans to cover the cost of vaccination for crew members on board its ships or on land through agreements with local governments.