A proposal submitted to the White House Tuesday by the leading cruise trade organization would deny cruise boarding to any person over 70 unless they present a doctor's note verifying their fitness for travel. And one cruise line is already acting on it.

Cruise Lines International Association (CLIA) submitted a plan to Vice President Michael Pence proposing enhanced measures across the industry as the coronavirus pandemic rages on, forcing two ships of passengers into quarantine and escalating fears on others.

According to the proposal, boarding should be denied to any person over the age of 70 years unless they are able to present a doctor's note verifying their fitness for travel on a cruise ship, according to a person familiar with the situation but not authorized to speak publicly.

Similarly, any person with a chronic medical condition who could be at an increased risk if they were to contract COVID-19 should be barred from getting on a cruise ship.

At a briefing Tuesday night, Pence confirmed he had received CLIA's proposal. "We'll be reviewing that in the next 24 hours," he added. "The President's objective is for us to make cruise lines safer, even as we work with the cruise lines to ensure that -- that no one in our particularly vulnerable population is -- is going out on a cruise in the near future."

The group also proposed additional restrictions based on where cruise passengers have traveled.

Norwegian enacts over-70 policy

Norwegian Cruise Line is not waiting for the White House to approve CLIA's plan.

Late Wednesday, Norwegian sent out an email to passengers on upcoming voyages stating that all guests who are over the age of 70 need to provide a certificate of medical fitness form before boarding.

The cruise line provided a link to the form on its website.

"If you are 70 years of age and older, please bring the completed form with you as you will be required to present the form prior to embarkation. Those who do not present the form will be denied boarding and will be issued a future cruise certificate for the value of their cruise," Katty Byrd, vice president of guest services for Norwegian Cruise Line said in a copy of the email obtained by USA TODAY.

The form has to be signed by a licensed medical professional no more than seven days ahead of embarkation or seven days before the guest's travels began if they are traveling more than seven days before a voyage's start time.

"This update to our health and safety policies is being implemented immediately across our ships that embark or disembark in a U.S. port," Byrd continued. "While we apologize for any inconvenience, we are taking significant comprehensive preventative measures to maintain the safety and well-being of our guests and crew. We greatly appreciate your attention to this very important matter."

CLIA also recommends adding Japan, Italy to list of countries on no-go list

The recommendation from CLIA to the White House suggests that Japan and Italy should be added to the list of countries whereby passengers and crew will be denied boarding if they have traveled there within 14 days prior to embarkation.

CLIA already had several regions in northern Italy on its list of denied areas but it is now recommending the entire country be included, according to the source. Other countries on the current list include South Korea, Iran, China, Hong Kong and Macao. Some lines, such as Celebrity and Costa and had proactively added Japan to their own lists of denied countries.

Additionally, CLIA added initial embarkation temperature screenings over the weekend. Anyone with a temperature at or higher than 100.4 will be denied boarding. Before the new policy was instituted, that would have resulted in a secondary medical assessment.

As of Thursday morning, coronavirus had infected more than 127,860 people and killed 4,718 globally, according to Johns Hopkins data.

The passengers of two of Princess Cruises' ships, Diamond Princess and Grand Princess, have been quarantined abroad and in the U.S., respectively. Nearly 700 people contracted coronavirus after being quarantined on board the Diamond Princess, where they were held for nearly two weeks off the coast of Japan. At least 21 people have tested positive after being on Grand Princess, which began offloading passengers in Oakland, California, Monday.

On Thursday, Princess announced it was suspending all operations for 60 days (through May 10) in a statement shared with USA TODAY by spokesperson Negin Kamali.

Cruise industry fallout: Princess Cruises suspends operations for 60 days; Viking Cruises cancels all cruises due to coronavirus

Passengers currently on cruises scheduled to end within the next five days will continue to sail as expected so onward travel arrangements are not disrupted. However, voyages that extend past March 17 will be cut short at a convenient disembarkation location for guests.

Other ships have been turned away from ports for fear of the virus, including Holland America's MS Westerdam, which found itself in limbo in February before being allowed to disembark in Cambodia.

Since the outbreak began, CLIA has issued increased screening measures and updated them on a few separate occasions.

CLIA is the largest cruise trade industry and the voice and "leading authority" for the global cruise community. Its member ships make up 95% of ocean-going cruises.

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