A growing number of Americans say they're ready to cruise again.
But when will they be allowed to get back on a cruise ship?
Whenever cruise vacations return some cruise companies like Virgin and Crystal will require everyone, passengers and crew, to be vaccinated.
Some analysts believe with new health protocols, ships could resume cruising again as early as July.
For close to a year: vessels have been in port, idle, sitting empty.
More than 250 ships are still without passengers during this unprecedented shutdown.
Unlike restaurants, sports stadiums, schools, which open when governors and local governments say so, the lead authority that will decide when cruise lines can resume is the CDC.
But so far the CDC has issued no new health and safety protocols,
The CDC declined to talk to NBC news.
But the lack of clear guidelines has not stopped Americans from booking trips.
The best clues of how it may work in the US may come by looking at what works in Europe.
Everyone must test negative before boarding.
Masks are required. Ships are limiting the number of passengers.
Under those rules more than 350,000 people have cruised since last July in Europe.
Only about 50 passengers have tested positive for COVID while at sea, according to the Cruise Line International Association.
Similar rules could be adopted by the United States.
And the traditional safety muster where everyone used to crowd at lifeboats will be a thing of the past.
It's all moving to an app.