World Health Organization epidemiologist Maria Van Kerkhove gestures as she speaks during a daily press briefing on COVID-19 at the WHO headquarters in Geneva on March 9, 2020. (FABRICE COFFRINI / AFP)

GENEVA/ZURICH - An upward revision in China’s coronavirus death toll on Friday was “an attempt to leave no case undocumented” after medical services in Wuhan were overwhelmed at the start of the outbreak, the World Health Organization (WHO) said.

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A total of 1,290 people were added to the toll in Wuhan after the city government included those who died at home and corrected some inaccuracies in reporting that occurred in the early stages of the outbreak, the Wuhan headquarters for COVID-19 epidemic prevention and control said in a notification on Friday.

I would anticipate that many countries are going to be in a similar situation where they will have to go back and review records and look to see did we capture all of them

Maria van Kerkhove, WHO epidemiologist 

Maria van Kerkhove, a WHO epidemiologist who took part in an international mission to China in February, said of China’s revised figures: “This was done in attempt to leave no case undocumented.”

She said the Chinese authorities had gone back over data from funeral services, care homes, fever clinics, hospitals and detention centers, and patients who had died at home, in Wuhan, Hubei province where the outbreak began late last year.

“What they have reported is that the discrepancies in these cases were due to a number of factors. First is that the health care system in Wuhan was overwhelmed at one point. And some patients died at home,” van Kerkhove said.

“Secondly is that medical staff were delayed in reporting of these cases because they were focused on providing care for those patients and they didn’t fill out the forms in time,” she said.

Mild cases were treated in makeshift hospitals in Wuhan stadiums or other facilities, van Kerkhove said, adding: “In those situations the reporting wasn’t done in a timely manner and so those cases were added.”

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It was important to know the number of people who had died from the disease and to have “accurate reporting”, which can be a challenge during an outbreak, she said.

“I would anticipate that many countries are going to be in a similar situation where they will have to go back and review records and look to see did we capture all of them,” she said.

Dr. Mike Ryan, WHO’s top emergencies expert, said: “It is important that countries provide that data as quickly as they can in the interest of moving our collective efforts forward to control this pandemic.”