Thousands of people remain quarantined on a cruise ship off Japan as 41 new cases of the novel coronavirus have been confirmed among its passengers – including five Australians.

Twenty people on Diamond Princess had already tested positive to the deadly virus before Japanese authorities confirmed a further 41 positive tests on Friday.

The remainder of the 3700 passengers and crew were still waiting for test results. They include more than 200 Australians.

The surge in Australians confirmed to have the deadly infection came as the federal government confirmed a second plane was on its way to rescue evacuees from the Chinese city at the epicentre of the virus.

They will be housed at a former mining camp near Darwin for their two-week quarantine.

Prime Minister Scott Morrison said the government had been advised that the former Christmas Island detention centre – where 278 Australian evacuees have already been taken – could not properly segregate the next group of people from Wuhan.

"With that advice we will be moving to the contingency plans for overflow," Mr Morrison said on Friday.

The former Inpex workers' village housed 3500 workers at the height of construction of its $55 billion gas plant on Darwin Harbour.

Five Australians among 61 confirmed coronavirus patients on board cruise ship_1
The new Australian evacuees will be brought to the Inpex miners' village near Darwin. Photo: ABC

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On board the stricken Diamond Princess, confined passengers have spoken out about their living conditions on board. Queensland couple Paul and Jacqui Fidrmuc said it was a "frightening situation".

They were among those tested and must spend 12 more days in quarantine. They passed their medical testing but are concerned they still might have the virus.

"The concern we have is we might have the virus and we don't have the symptoms," Mr Fidrmuc said on Thursday.

"It's a frightening situation but it is not a disease where if you get it, it's certain death. You just have to be lighthearted about the whole situation."

The website for Diamond Princess issued an updated health advisory for its passengers, with many scheduled cruises being cancelled, delayed or diverted to other ports.

Also on Friday, Home Affairs Minister Peter Dutton warned Australians against travelling to China as the coronavirus continued to spread.

The federal government's official advice is avoid travel to China. But Mr Dutton said some people were ignoring that advice and "putting themselves in a difficult situation".

"They would find it very hard to get back to Australia in certain circumstances and you can't guarantee their return, particularly if China shuts its borders," he told the Nine Network on Friday.

-with AAP