The number of Australians who have contracted coronavirus on board a contaminated cruise ship anchored in Japan has climbed to 11.

Four Australians are among the 66 new cases detected on the Diamond Princess docked at Yokohama port, near Tokyo, it has been confirmed.

The infected people have been taken to hospitals in Japan for further assessments.

The surge in the number of infections on board comes after the death toll from the virus in mainland China rose by 97 on Sunday (local time) – the largest in a single day since the coronavirus outbreak in December.

The number of cases worldwide has reached more than 40,500, while more than 900 people have died from the virus, mainly in Wuhan.

Source: World Health Organisation

Early on Tuesday (Australian time), World Health Organisation chief Tedros Adhanom Ghebreyesus said the spread of coronavirus cases among people who have not been to China could be “the spark that becomes a bigger fire”.

“For now it is only a spark. Our objective remains containment,” he said.

“We should really fight hard as one human race to fight this virus before it gets out of control.” 

A Japanese flag with the words “medicine lacking” is draped on the quarantined cruise ship Diamond Princess. Some guests are elderly and on medication. #coronavirus #DiamondPrincess pic.twitter.com/iQncSy50tX

— Paula Hancocks (@PHancocksCNN) February 7, 2020

Japanese authorities have been trying to isolate the more than 3700 passengers on board the Diamond Princess to halt the virus’ spread.

The number of people with positive test results has now jumped to 136 and it’s expected anyone who has had close contact with those people will need to stay in quarantine for longer than the fortnight mandated for other passengers.

Melbourne passengers Karen and Jason Honey said they were shaken by the news that more people had become infected.

“But otherwise we are OK and are just trying to do one day at a time,” Ms Honey told ABC’s 7.30.

A Department of Foreign Affairs and Trade spokesman said the department is urgently seeking advice from Japanese authorities on the four new Australian cases.

On Monday, The New Daily revealed the quirky ways cooped-up passengers were managing to pass the time and the instructions given by health authorities to contain the virus which has spread to at least 27 countries and territories.

• Latest on Christmas Island quarantine: Third airlift of Wuhan evacuees lands in Darwin 

Health authorities originally handed everyone a thermometer and requested they take their temperatures regularly.

Day 3 of quarantine on the Diamond Princess cruise ship in Japan:
– More confirmed #coronavirus cases
– Aunt and uncle are given gloves and thermometers 🌡
– Uncle does tai chi with 🎵 #クルーズ船 #CoronavirusOutbreak pic.twitter.com/FpX0XGJK7s

— Virginia Lau (@virginiaylau) February 7, 2020

They proceeded to test only about 7 per cent of people on the ship who they deemed at-risk.

Testing has since been expanded to include those who’ve been in close contact with infected passengers.

All others have been placed under mandatory quarantine until February 19.

Therefore, the true scale of infections might not be reflected in the official number of coronavirus cases on board.

The Diamond Princess had about 3700 people on board. Photo: Getty

Sydney company shuts down offices

One global recruitment website is following in the footsteps of the many workplaces in China that remain closed. 

Sydney employees for Indeed have been asked to work from home due to concerns that one of its employees in Singapore might have been exposed to coronavirus.

Indeed has also requested that workers in its Dublin offices stay home to prevent the potential spread of the infection, the company said.

The employee in question had contact with family members who visited a facility caring for a coronavirus patient.

The company stressed that there were no confirmed cases of the virus and said the move was a precaution to avoid any possible risk to the health and safety of its employees.

Indeed employs about 9000 people globally, about 1000 of them in Dublin.

In China, where the epidemic has caused the most disruption, cities have become ghost towns as Communist Party rulers ordered lockdowns, cancelled flights and closed factories and schools.

Over the weekend, an American hospitalised in the central city of Wuhan became the first confirmed non-Chinese victim of the disease. A Japanese man who also died there was another suspected victim.

-with AAP