What you need to know now about the coronavirus: New method of diagnosing illness

The latest:

• Death toll reaches 1,367, up 254 from the previous day.
• Apparent spike in cases and death toll relates to new method of diagnosis for COVID-19.
• China has worked through backlog of cases from earlier in the outbreak, some now clinically confirmed positive.
• China now has 59,805 laboratory and clinically confirmed cases, up 15,152.
• Diamond Princess cruise ship docked in Yokohama, Japan, is largest cluster outside of China.
• 12 Canadians who were aboard have the illness.
• No additional countries are reporting cases.

A new method of diagnosing the illness caused by novel coronavirus is allowing front-line medical workers in China to get patients into care more quickly and public health departments to then track down people who may have come into contact with the virus.

At a World Health Organization news conference Thursday, Dr. Mike Ryan, executive director of WHO's emergency program, explained an apparent spike in deaths and new cases reported by Chinese authorities.

China now has 59,805 confirmed cases, up 15,152 from Wednesday, and the number of deaths increased by 254 to reach 1,367.

The increase comes after many suspect cases from Hubei province that had been backlogged were reclassified using patients' chest images, rather than waiting for laboratory confirmation, said Ryan.

So, the increase is largely due to a change in how cases are being diagnosed and reported, he said.

"Crucially, we understand that most of these cases relate to a period going back over days and weeks and are retrospectively reported as cases, sometimes back to the beginning of the outbreak itself," he said.

"We've seen this spike in the number of cases reported in China, but this does not represent a significant change in the trajectory of the outbreak."

The number of countries reporting cases of the illness has held steady at 24.

Higher numbers may contain some good news

Medical experts say the higher numbers likely reflect a more accurate picture of the illness.

Dr. Mike Tildesley, an associate professor at the University of Warwick in the U.K. who studies zoonotic diseases — those that spread from animals to humans — said many of these new cases were previously defined as "probable" cases.

"Given this change in classification, it is unsurprising that we have seen an increase in confirmed cases, but this does not necessarily mean that we are seeing an increase in the rate of infection," he said in a written statement.

"What it does mean is that we may now have a more accurate measure of the true extent of the outbreak, which in the longer term will improve our ability to predict how the virus may spread in the future." 

Indeed, cases are not rising dramatically outside China apart from among passengers on a cruise liner now quarantined off the Japanese port of Yokohama, said Ryan.

12 Canadians test positive on cruise ship

A further 44 cases were reported on the vessel Thursday, raising the total to 219. Authorities said some elderly people would finally to be allowed to disembark on Friday.

Foreign Affairs Minister François-Philippe Champagne said 12 Canadians who were aboard the ship have contracted COVID-19.

They've since been moved to Japanese health facilities, and at least three require hospitalization, he said.

Champagne said emergency response teams and consular officials are in Japan to make sure Canadians are receiving the help they need.

"We know that there are some people who need medications on board, they want to have contact with their families, we're facilitating that," Champagne said at a briefing in Senegal, where he is on a diplomatic trip.

As for Canadians still in the centre of the viral outbreak, Champagne said all the 400 or so Canadians who wished to leave Hubei, the Chinese province that includes the city of Wuhan, have been repatriated and are quarantined in southern Ontario, at Canadian Forces Base Trenton.

The last flight chartered by the Canadian government to evacuate people from Wuhan, which landed at CFB Trenton on Tuesday, was the last the government plans to send to the region. Those Canadians who chose to stay behind in Hubei have been provided with consular services, Champagne said.

Death toll steady around 2%

Mark Fielder, a professor of medical microbiology at London's Kingston University, said the new clinically confirmed cases are now added to those previously identified only through nucleic acid-based lab tests.

"I am reassured that despite the rise in numbers, the death rate still stands at around two per cent," said Fielder.

"As it stands, I think the data and the situation remain one that we need to have global eyes fixed upon. We should be concerned and take it seriously, but not worry."