Virus death toll soars as China changes counting methods

China's official death toll from the new coronavirus has spiked dramatically, with 242 deaths reported in a single day, after authorities changed their counting methods. This has fuelled concern that the epidemic is far worse than is being admitted officially.

As the figures soared in China, a troubling new front opened abroad as neighbouring Vietnam placed 10,000 people under quarantine after six COVID-19 cases were discovered in a cluster of villages -- the first such action taken in a country other than China.

Under criticism at home over the handling of the crisis, China's Communist Party sacked two top-ranking officials in Hubei province, the epicentre of the outbreak.

Xi claims positive results

The developments came hours after President Xi Jinping claimed "positive results" from efforts to contain an epidemic that has now officially killed more than 1,350 people.

But the World Health Organization warned it was too soon to declare victory.

"I think it is way too early to try to predict the beginning, the middle or the end of this epidemic right now," said Michael Ryan, head of the WHO's health emergencies programme.

In Hubei and its capital Wuhan, where tens of millions of people are trapped as part of an unprecedented quarantine effort, 242 new deaths were reported on Thursday.

Biggest one-day increase so far

Another 14,840 people were confirmed to be infected, with the new cases and deaths by far the biggest one-day increases since the crisis began.

Hubei authorities said the increases were because they had broadened their definition for infection to include people "clinically diagnosed" via lung imaging.

Previously, they had been identifying cases on the results of laboratory tests.

The additions raised the death toll to 1,355 and the total number of infections nationwide to nearly 60,000.

Markets get the jitters

Share values on Asian financial markets fell on Thursday after the dramatic spike in the number of coronavirus deaths and cases in mainland China, with traders concerned about the economic impact of the epidemic.

Also on Thursday, Australia announced that the ban on travellers from China would extend for at least a week beyond Saturday's planned deadline.

Prime Minister Scott Morrison said the government would maintain "entry restriction on foreign nationals who have recently been in mainland China" for at least another week "to protect Australians from the risk of coronavirus".

A decision to extend the ban further will be taken week-to-week, he said.

Japan has, meanwhile, announced the first death of a person infected with Covid-19. The victim was a woman in her 80s, and the health minister warned that it was not clear if the virus caused her death.

"The relationship between the new coronavirus and the death of the woman is still unclear," Katsunobu Kato said at a late-night briefing.

"This is the first death of a person who tested positive."