Australian evacuees from a virus infected cruise ship in Japan have arrived in Darwin for isolation as the government extends the travel ban.

Australia has extended its ban on foreign travellers from China for another week as the number of infections and deaths in the coronavirus epicentre of Hubei province continues to grow.

The decision was made as 170 evacuees from a coronavirus-hit cruise ship off Japan arrived in quarantine in Darwin.

Six people suffering a sore throat and runny nose have been tested and separated from the rest of the group who arrived at the former Inpex LNG project workers camp at Howard Springs that will be their home for a fortnight.

The Australians in Darwin, mostly aged in their 60s and 70s, but some over 80, had already been quarantined on the Diamond Princess in Yokohama for two weeks, effectively leaving them confined for almost a month.

"Six people (who) were identified as having minor sniffles and sore throats have been separated completely, these people were tested today and they have gone into an isolation area of the Howard Springs facility," Acting NT chief health officer Dianne Stephens said.

Two Japanese passengers on the Diamond Princess aged in their 80s have died, Japanese media reported on Thursday.

The number of confirmed cases of coronavirus on the ship, which was carrying 3700 passengers and crew, has topped 620 and includes 36 Australians, all of whom are stable, which has prompted criticism of quarantine measures on board.

"Whether it is us or the crew, we just wanted to get off this damn ship," Australian Vera Koslova-Fu told ABC before boarding the flight in Japan.

She said she had been tempted to stay in Japan but decided to fly home saying "If Australia decides, 'Oh no, the pandemic is getting worse you are going to have to stay away, you are not allowed to come in', then we are basically stuffed".

The federal government announced on Thursday that Australia's ban on travellers from China has been extended until February 29.

The Chinese government had asked Australia to rescind the ban, saying it was excessive and an overreaction.

"Unfortunately, the number of infections and deaths in Hubei province itself continues to grow," a joint statement by Prime Minister Scott Morrison, Foreign Affairs Minister Marise Payne and Health Minister Greg Hunt said.

There have been 15 confirmed cases of the disease in Australia, with eight people recovered and the rest in stable conditions, which indicated "the government's precautionary approach to preventing the spread of coronavirus on our shores continue to be successful" the statement said.

So far there have been more than 75,300 cases recorded worldwide and 2012 deaths, almost all of which were in China.