Norwegian Cruise Line, Oceania Cruises and Regent Seven Seas Cruises have all canceled their sailings through Dec. 31
Norwegian Joy sea trial
Norwegian Cruise Lines

Three major cruise lines will not set sail until next year.

On Monday, Norwegian Cruise Line, Oceania Cruises and Regent Seven Seas Cruises announced that they would be pausing their cruise operations through Dec. 31.

The parent company of the three brands, Norwegian Cruise Line Holdings, had previously halted operations through the end of November, according to The Points Guy.

Their decision to extend the pause comes after the Centers for Disease Control and Prevention (CDC) released an updated conditional sailing order on Friday, lifting their no-sail ban and replacing it with a list of new health protocols and a "framework of actionable items" for cruises to follow beginning Nov. 1.

The order — which applies to ships with the capacity to carry at least 250 passengers and travel in U.S. waters — details how cruise lines should take a "phased approach for the safe and responsible resumption of passenger cruises," making it clear that no passengers will be allowed to sail at this time.

"This framework provides a pathway to resume safe and responsible sailing. It will mitigate the risk of COVID-19 outbreaks on ships and prevent passengers and crew from seeding outbreaks at ports and in the communities where they live," CDC Director Robert R. Redfield, M.D said in a press release. "CDC and the cruise industry have a shared goal to protect crew, passengers, and communities and will continue to work together to ensure that all necessary public health procedures are in place before cruise ships begin sailing with passengers."

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The CDC is requiring that all cruise companies have additional testing and social distancing requirements before they can move forward and operate mock voyages. Ships will then sail on simulated voyages with volunteers pretending to be passengers to "test cruise ship operators' ability to mitigate COVID-19 risk," according to the release.

Cruise companies who are able to meet these requirements and obtain proper certification will then be on track to "return to passenger voyages in a manner that mitigates COVID-19 risk among passengers, crew members, and communities."

“Cruise ships are incubators,” infectious disease expert Dr. William Haseltine previously told PEOPLE. “Everybody’s close together, packed in all the time. One person gets sick, a lot of them get sick. It’s a very unfavorable environment for disease transmission.”

The CDC first issued a no-sail order on March 14 intended to stay in place for 30 days. At the time, several cruise ships across the world had become the sites of major coronavirus outbreaks and numerous deaths.

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