April 23, 2020 - 10:59 AMT
China Covid-19 cases might have been four times the official figure: study

A study by Hong Kong researchers shows that more than 232,000 people might have been infected in the first wave of Covid-19 in mainland China, four times the official figures, The Guardian reports.

Mainland China reported more than 55,000 cases as of 20 February but, according to research by academics at Hong Kong University’s school of public health published in the Lancet, the true number would have been far greater if the definition of a Covid-19 case that was later used had been applied from the outset.

China has now reported more than 83,000 cases. Globally, the death toll from the coronavirus has exceeded 183,000, with the number of cases worldwide standing at more than 2.6 million.

China’s national health commission issued seven versions of a case definition for Covid-19 between 15 January and 3 March, and the study found these changes had a “substantial effect” on how many infections which were detected as cases.

The Hong Kong study analysed data up to 20 February culled from the World Health Organization’s mission to Wuhan.

It estimated that each of the first four changes increased the proportion of cases detected and counted, by between 2.8 and 7.1 times.

“If the fifth version of the case definition had been applied throughout the outbreak with sufficient testing capacity, we estimated that by 20 February 2020, there would have been 232,000 … confirmed cases in China as opposed to the 55,508 confirmed cases reported,” the study said.