The Chinese province at the epicentre of the coronavirus outbreak has reported a record rise in the death toll and infection numbers, as global health experts warn the epidemic could get far worse before it is brought under control.

Key points: The previous record rise in the toll was 103 on February 10

The previous record rise in the toll was 103 on February 10 Experts say a vaccine could still be months away

Experts say a vaccine could still be months away Hundreds of infections have been reported in over two dozen other countries and territories

The spike is partly attributed to a new diagnostic method which allows health authorities to diagnose the virus more quickly.

Health officials in Hubei province said 242 people had died from the flu-like virus on Wednesday, the fastest rise in the daily count since the pathogen was identified in December, and bringing the total number of deaths in the province to 1,310.

The previous highest rise in the toll was 103 on February 10.

The new tally came a day after China had reported its lowest number of new coronavirus cases in two weeks, bolstering a forecast by Beijing's senior medical adviser for the outbreak there to end by April.

But the 2,015 new confirmed cases reported in mainland China on Wednesday was dwarfed by the 14,840 new cases reported in Hubei alone on Thursday, when provincial officials said they had adopted a new methodology for counting infections.

The World Health Organisation on Wednesday named the virus COVID-19, explaining that it was important to avoid stigma and that other names could be inaccurate.

CT scans see cases diagnosed sooner

The provincial health commission said last week that it would begin recognising computerised tomography (CT) scan results as confirmation of infections, allowing hospitals to isolate patients more quickly.

It also said it had revised its old data and previous assessments of suspected cases.

Health officials in the province said they had started including people diagnosed using the new methods from Thursday.

Hubei had previously only allowed infections to be confirmed by RNA tests, which can take days to process. RNA, or ribonucleic acid, carries genetic information allowing for identification of organisms like viruses.

Excluding cases confirmed using the new methods, the number of new cases rose by only 1,508, the official data showed.

Using CT scans that reveal lung infection would help patients receive treatment as soon as possible and improve their chances of recovery, the Hubei health commission said.

It could also lead to a spike in the death toll, according to Raina McIntyre, head of biosecurity research at the Kirby Institute at the University of New South Wales in Sydney.

"Presumably, there are deaths which occurred in people who did not have a lab diagnosis but did have a CT. It is important that these also be counted." she said.

A shortage of RNA test kits in Hubei's capital Wuhan has been a problem and may have delayed patients from being properly diagnosed and treated, contributing to the spread of the virus in the early days of the outbreak, Reuters previously reported.

Results from Chinese trials testing a combination of antiviral drugs used to treat HIV against the new coronavirus are due in weeks, but experts said a vaccine could still be months away.

China's Communist Party sacks top officials in Hubei

Officials in Hubei have been heavily criticised for their handling of the epidemic in a province of almost 60 million people.

On Thursday, China's state-run media outlet Xinhua reported the Communist Party had sacked the province's high-profile officials.

According to the reports, Jiang Chaoliang has been sacked as secretary of the Hubei Provincial Committee and replaced with Shanghai Mayor Ying Yong.

Mr Ying worked closely with the Chinese President Xi Jinping during the latter's time as party boss and governor of Zhejiang province.

Wuhan party chief Ma Guoqiang has also been removed, replaced by Wang Zhonglin, party boss of Jinan city in eastern Shandong province.

The reports did not state a reason for the dismissals, but the two are the most high-profile Chinese officials to date to be removed from duty following the coronavirus outbreak that began in Wuhan late last year.

"Thank you Communist Party. It should have been done earlier," Wuhan resident Wang You told Reuters.

Dozens of low-level health officials across the country have also lost their jobs for failing to contain the spread of the epidemic.

'Outbreak could still go in any direction'

Hundreds of infections have been reported in more than two dozen other countries and territories. ( AAP: Mick Tsikas )

World Health Organisation (WHO) chief Tedros Adhanom Ghebreyesus warned any apparent slowdown in the spread of the epidemic should be viewed with "extreme caution".

"This outbreak could still go in any direction," he told a briefing in Geneva.

Another expert said that while the coronavirus may be peaking in China, this was not the case elsewhere.

"It has spread to other places where it's the beginning of the outbreak," Dale Fisher, head of the Global Outbreak Alert and Response Network coordinated by the WHO, said in an interview in Singapore.

"In Singapore, we are at the beginning."

Singapore had a total of 50 cases, including one found at its biggest bank, DBS, on Wednesday that caused an evacuation at the head office.

Hundreds of infections have been reported in more than two dozen other countries and territories — including 15 in Australia.

Only two people have died from the virus outside mainland China, one in Hong Kong and another in the Philippines.

Mr Tedros said a WHO-led advance team that travelled to China this week had made good progress on the composition and scope of its work.

The head of the WHO's emergency program, Dr Mike Ryan, said it was too early "to predict the beginning, the middle or end of the epidemic".

Passengers to be evacuated from stricken cruise ship

The biggest cluster of cases outside China is on a cruise ship, the Diamond Princess, quarantined off the Japanese port of Yokohama, with 219 of about 3,700 people on board having tested positive.

Japanese health officials will evacuate 44 people who were diagnosed on Thursday.

They also plan to remove passengers who are aged 80 or above, or have an existing serious illness, or are staying in rooms without windows.

People diagnosed with coronavirus are being taken off the Diamond Princess and treated in isolation wards. ( Reuters: Kim Kyung-Hoon )

Those passengers must test negative for the virus and if so, will be taken to a facility prepared by the Government.

Melbourne immunologist Erika Cretney, who works at the Peter McCallum Cancer Centre, had expressed concern for her parents after her father was removed from the Diamond Princess after being diagnosed with the coronavirus and taken by Japanese health authorities to an unknown location.

But late on Thursday she was told where her father, Edgar Krasovkis, was being treated.

Reuters