The Chinese province at the heart of the coronavirus outbreak changes how it counts cases—again

February 20, 2020, 11:08 AM UTC

The number of new coronavirus cases reported by Hubei province dropped sharply after China changed the way it officially reports the number of infections for the second time in a month, raising questions over the reliability of data from the epicenter of the outbreak.

In its daily tally, Hubei said on Thursday that it had just 349 additional confirmed cases, compared with almost 1,700 additional cases from the day before.

No official explanation was given for the sudden decline, but it came a day after new national guidelines advised the province to only report two numbers in its overall count: confirmed and suspected cases, in line with how other provincial and national figures are reported.

Prior to that, Hubei had been reporting whether new cases of infection were confirmed via CT scans, known as “clinical diagnosis,” or nucleic acid tests. This practice was itself in place for only a week, and resulted from a methodology change made on Feb. 13 which abruptly added nearly 15,000 cases to its total count.

The shifting classification guidelines, and the lack of clarity over what’s included in China’s official count, forced yet another re-calculation of the contours of the crisis that has infected over 70,000 and killed over 2,000.

WUHAN, CHINA - FEBRUARY 18, 2020 - Patients at night in the Fangcang hospital, Wuhan, Hubei Province, China, February 18, 2020.- PHOTOGRAPH BY Costfoto / Barcroft Media (Photo credit should read Costfoto/Barcroft Media via Getty Images)
Patients at night in the Fangcang hospital, Wuhan, Hubei Province, China, on Feb. 18, 2020.
Costfoto/Barcroft Media via Getty Images

There is growing mistrust over official data emerging from China, which has the vast majority of coronavirus cases and deaths globally, and suspicion that the country’s officials are prematurely promoting a narrative that the outbreak is coming under control.

The National Health Commission did not respond to questions seeking clarity over the latest data. A report from state-run news agency Xinhua on Thursday cited the Hubei health commission saying that some cases previously confirmed via CT scans were re-classified upon review by medical experts. But it didn’t explain the large drop in new cases for the province as a whole compared to a day ago.

“It points to a rather concerning confusion over how best to officially report the number of cases, leading to a loss of confidence in the true numbers,” said Jeffrey Halley, a Singapore-based senior market analyst with Oanda Asia Pacific Pte. “That could mean that internationally, the rest of the world keeps China in lockdown for longer, which will not be good for the ‘V-shaped recovery’” projections, he said.


Timeline of Events

Feb. 5—China advises Hubei province to separate cases diagnosed via CT scans as a separate category within its total count of confirmed cases.

Feb. 13—Hubei reports more than 13,000 cases confirmed via CT scans, without specifying a time frame, raising the total by 45% and pushing the global number of infections to over 60,000.

Feb. 14—China revises its total death toll lower, saying that 108 deaths had been removed due to “double-counting” in Hubei. It also removes 1,043 confirmed cases.

Feb. 19—China advises Hubei province to report cases only as “confirmed” or “suspected,” removing the need to carve out a category of cases diagnosed via CT scans.

Feb. 20—Hubei reports only 349 new cases, compared to nearly 1,700 the day before.


CT scans are an alternative method that doctors in Hubei have been using to spot signs of pneumonia in patients due to the lack of nucleic acid test kits that can identify the virus’ genetic sequence in patients. The kits themselves were also known to sometimes throw up false negatives.

In recognition of the inadequacy of testing kits, China advised Hubei province on Feb 5. to begin including patients diagnosed via CT scans as a separate category under its overall count. The province started doing so on Feb. 13 in a shock adjustment that sent its total count up by 45%.

A day later, China’s National Heath Commission removed 108 deaths from its total number due to “double-counting” in Hubei.

“It is not normal for case definitions to be changed so frequently,” said Ben Cowling, a professor of epidemiology at Hong Kong University. “I imagine that the change in case definitions has led to a change in testing practice, that is, less use of the method of clinical diagnosis via CT scans.”

Tommy Xie, an economist at the Oversea-Chinese Banking Corp, saw the latest change as a refining of the previous adjustment and no cause for concern.

“There is no need to question China’s data transparency,” he wrote in a note published Thursday. “What we are seeing right now is the convergence of the counting method in Hubei towards the national standard.” This suggests that the nucleic acid test kit shortage in Hubei has eased, so diagnosis via CT scans is no longer valid without additional confirmation from a test, he wrote.

Uncertainty and Opacity

The latest changes cast doubt over whether the drop in new cases — a positive sign that the epidemic is coming under control at the epicenter — can be taken at face value. In recent days, China’s leaders have sought to project optimism over the outbreak, which has shut down large parts of its economy and plunged industries from retail to aviation into crisis.

Companies and factories across China are now being urged to re-start economic activity, while Chinese premier Li Keqiang said on Monday that the outbreak is on “a positive trend.”

Troubled companies in China are starting to crumble under the strain, intensifying the pressure on China’s leaders to prop up its overall economy. The government is considering direct cash infusions or mergers to stabilize the hobbled airline industry, while the People’s Bank of China said it will work on supporting domestic consumption.

The government of Hainan, the southern island province where indebted conglomerate HNA Group Co. is based, is in talks to seize control of the group after the contagion hurt its ability to meet financial obligations, according to people familiar with the plans.

In this climate, the latest methodology change in Hubei province is raising more questions than it answers.

“I think there may be genuine attempts to report as accurately as possible and this may be just a way of refining the numbers,” said Vishnu Varathan, Singapore-based head of economics and strategy at Mizuho Bank, Ltd.

“But the pertinent point is that in this climate of uncertainty and opacity around what is going on, constant revisions may breed mistrust, which in turn is amplified by social media.”