China has been facing criticism for not being transparent with the world bodies and other countries about the Coronavirus outbreak which emerged in Hubei's Wuhan city in December 2019.
Along with conspiracy related to the Wuhan Institute of Virology, which many experts believe to be the source of the novel Coronavirus, the death toll which Chinese officials have released as of now is also another topic which continues to create claims, focusing that the fatality rate in China is much higher than the world knows.
Now a research study from the University of Hong Kong revealed that the official tally of COVID-19 cases could have quadrupled in February if one broader system for classifying confirmed patients had been used from the outset of the Coronavirus pandemic.
New study on China Coronavirus cases
The new research was published in the medical journal The Lancet on Tuesday. In the study, the researchers have stated that China might have had 232,000 confirmed novel Coronavirus cases, rather than the official total of about 55,000 by February 20, if a revised definition adopted earlier in the month had been applied throughout the country.
The researchers said, "We estimated that there were at least 232,000 infections in the first epidemic wave of COVID-19 in mainland China. The true number of infections could still be higher than that currently estimated considering the possibility of under-detection of some infections, particularly those that were mild and asymptomatic, even under the broadest case definitions."
For this study, led by Peng Wu from the University of Hong Kong's school of public health, researchers looked at the various classification systems used by the CCP after the epidemic erupted in Wuhan. The authorities have published seven editions of diagnosis and treatment guidelines, changing the classification system as an understanding of the COVID-19.
Hong Kong research reveals what China did not
The research paper, co-authored by Peng's HKU colleague epidemiologist Benjamin Cowling and medical faculty dean Gabriel Leung, revealed that the researchers "estimated that when the case definitions were changed from version 1 to 2, version 2 to 4, and version 4 to 5, the proportion of infections being identified as COVID-19 cases was increased by 7.1 times from version 1 to 2, 2.8 times from version 2 to 4, and 4.2 times from version 4 to 5."
In fact, this calculation was based in the epidemiological curves included in a World Health Organisation (WHO) report that was published on February 28 after the Geneva-based international agency conducted a mission to Wuhan. These carves have shown the number of new Coronavirus cases based on symptom onset dates and reporting dates.
On February 5, as per the reports, in the fifth version if the COVID-19 guidelines the Chinese authorities had modified its classification of confirmed cases to include diagnosis by COVID-19 symptoms only instead of requiring confirmation by both clinical symptoms and laboratory tests. As per the research, the inclusion of these cases in China led to a sudden jump in confirmed numbers of the Coronavirus infection cases before the authorities reversed the decision more than a week later on February 17.
As per the team of researchers from Hong Kong, if the fifth definition were used throughout the epidemic, the total number of confirmed cases could have reached 232,000 by February 20. However, the impact of the later version of COVID-19 guidelines cannot be measured as no data based on symptom onset dated after February 20 has been released yet.
The researchers also noted that if the revisions of case classifications were taken into account, the original novel Coronavirus growth rate in China estimate would be an overestimate, and epidemiological studies should take into account changes in case definitions.