German cruise ship Mein Schiff 2 (My Ship 2), operated by travel giant TUI, set sail on Friday night from the northern city of Hamburg for a three-day round trip in the North Sea.

The vessel is carrying around 1,200 passengers, compared to its usual capacity of 2,900.

The company had said 1,740 would be allowed to travel, but that quota was not reached.  

Guests will spend the weekend at sea with no stops on land, eventually returning to Hamburg on Monday morning.

Read more: Pandemic forces German cruise ship-builder into temporary shutdown

Passengers will be required to observe strict physical distancing and hygiene measures on board. They were required to fill out a health questionnaire before boarding, and will not be allowed to serve themselves food at the buffet table. 

"It's basically a pragmatic solution where companies are trying to adapt processes to the new situation and get the business going again," Alexis Papathanassis, professor for Cruise Tourism Management, told German magazine Der Spiegel.

"But now is not the time for a hasty reaction," he warned. "Such process changes, hygiene protocols and contingency plans have to be developed systematically and professionally, be transparent and be tested," he said, stressing that "customers must not be used as test objects."

Also, the expert underlined, "a cruise that mainly consists of sea days and social distancing does not correspond to what I consider an attractive holiday experience."

Read more: Coronavirus fallout: Cruising into the unknown

Massive pandemic losses for cruise industry

The COVID-19 pandemic has largely left global tourism at a standstill, with the cruise industry particularly hit hard by the crisis as companies were forced to suspend voyages.

The sector's reputation has also taken a severe hit by instances where cruise ships were stricken with severe outbreaks, including the Diamond Princess in Japan.

Reports show the coronavirus broke out on at least 55 ships across the world's oceans. Some public health experts said the vessels helped carry the virus around the globe. Many sailed for weeks after the disease was first detected on a cruise liner. Ports eventually refused them entry, stranding tens of thousands of passengers and crew at sea — some for months.

Nevertheless, several cruise operators intend to relaunch trips for tourists in the coming weeks, after suffering massive financial losses in recent months. European river cruises are also making a quiet comeback on the Danube.

Germany and other EU countries began opening their borders in mid-June in an attempt to reinvigorate the travel sector during the crucial summer months.

Germany's health ministers have agreed to a federal framework that would require people returning from trips abroad to undergo testing for COVID-19. Testing facilities are to be set up at airports and harbors so that travelers can be screened.

In the US, however, federal health officials have extended the US ban on cruise ships through the end of September. In the order signed by the director of the US Centers for Disease Control and Prevention, Robert Redfield, the agency said the cruise industry hasn't controlled transmission of the virus on its ships.

The CDC said cruise ships are more crowded than most urban settings, and even when only essential crew remains on board, the virus continues to spread.

sri/mm (dpa, AP, Reuters)