The death toll from a new coronavirus in mainland China jumped by 73 to 563 on Thursday, its third-consecutive record daily rise, as experts stepped up efforts to find a vaccine for a disease that has shut down Chinese cities and forced thousands of others into quarantine around the world.

Hubei province, the epicentre of the epidemic, reported 70 new deaths on Wednesday and 2,987 new confirmed cases. The other fatalities were in Tianjin city, the northeastern province of Heilongjiang and Guizhou province in the southwest.

Hubei in central China has been almost sealed off for nearly two weeks with its railway stations and airports shut and roads blocked. The flu-like virus was first identified in Hubei's provincial capital of Wuhan and is believed to have originated at a seafood market in the city.

There have been two deaths outside mainland China - in the Philippines and Hong Kong - involving people who had been to Wuhan.

Hundreds of foreigners have been evacuated from the city and placed in quarantine centres around the world and thousands of passengers and crew were being confined to two cruise ships in Japan and Hong Kong.

Ten more people on the Diamond Princess in the Japanese port of Yokohama, south of Tokyo had tested positive for the coronavirus, the Japanese health ministry said, bringing the total number of cases on board to 20.

About 3,700 people are facing at least two weeks quarantined on the liner after an 80-year-old Hong Kong man who travelled on it late last month tested positive.

Al Jazeera's Fadi Salameh, who is in Yokohama, said the authorities would be delivering 7,000 masks to those on board. 

"Experts are worried the virus could spread in such a congested and enclosed space," he said. "They have also advised passengers not to leave their rooms." 

Some of the passengers were hopeful they would be evacuated.

"It’s better for us to travel while healthy and also if we get sick to be treated in American hospitals," Gay Courter, a 75-year-old American novelist on board the ship, told Reuters.

In Hong Kong, 3,600 passengers and crew remain quarantined on their ship - the World Dream - after three people on board were found to have coronavirus.

AL Jazeera