Six more passengers of a cruise ship quarantined off Japan have been diagnosed with coronavirus, bringing the total number of cases on board to 70.

The 3700 passengers on the Diamond Princess have been under quarantine off the coast of Yokohama for the past week, with eight days to go before they will be allowed ashore.

Among those on board are 219 Australians who are well, and another seven Australians among the 64 passengers that have tested positive.

< PREVIOUS SLIDE SLIDE 1 of 3 NEXT SLIDE > The Diamond Princess still has eight more days of its quarantine to go. (9News) © 9News

Eighty per cent of the passengers are aged over 70, making them more susceptible to the virus.

The Princess has faced numerous hurdles during its time under quarantine, including the disposal of excrement and sourcing food and medical supplies.

Passengers have now run out of prescription medication, with the huge number of patients on board causing a logistical nightmare for those trying to get newly-ordered drugs to their rooms.

The cruise ship is one of several around the world that has been left stranded as nations attempt to stem the spread of the deadly outbreak.

In pictures: Coronavirus outbreak

The World Dream vessel in Hong Kong has been confirmed to have coronavirus on board. Sixteen Australians are among the passengers, none of whom are ill.

Another ship, the Westerdam, has been stranded at sea after the Japanese, Philippines and South Korean governments refused it permission to dock despite no reported cases of the virus on board.

Westerdam passenger David Holst, from Adelaide, posted on Facebook today that Guam has also rejected the ship.

"We think we are safe on board in virtual quarantine but Holland America have a history of not telling us everything so we have nagging doubts," he wrote.

"We are eight days out of Hong Kong and I don't imagine any country will let us off until we are 14-15 days virus free."

Australia has so far had 15 confirmed coronavirus cases on its shores: five in Queensland, four each in NSW and Victoria and two in South Australia.

With AAP.

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