Death rates among hospitalised Covid patients halve since first wave
China’s chief epidemiologist Wu Zunyou has said that mass testing of millions of people is costly “overkill,” Sophia Yan reports.
“From the scientific perspective of epidemiology, it is unnecessary to test everyone,” Mr Wu told Chinese state media.
Local officials in the city of Qingdao recently rushed to test all 9 million residents over five days – the first step that Chinese authorities have taken to combat subsequent outbreaks of coronavirus after it emerged in Wuhan. In the end, only 12 results came back positive.
“But this kind of judgement is based on expertise and can only be 95 to 99 per cent accurate,” said Mr Wu. There is a “1 per cent to 5 per cent chance of uncertainty”.
Even a sliver of uncertainty drives local officials to conduct mass testing, especially as they’re keen to show the central government in Beijing that everything possible is being done to control the spread of coronavirus.
Bureaucrats think “if you test everyone…it will provide 100 per cent reassurance the outbreak has been contained”.
Rather, it’s sufficient to stop mass testing when the first batches mostly come back with negative results, as officials did in June in Beijing in response to a cluster outbreak, he said. Detailed contact tracing will also be useful.
At first, city authorities planned to test the entire city of 20 million, but finally stopped halfway through at the urging of experts as many tests came back negative.
“When tests of tens of thousands of people, or hundreds of thousands, returned negative, data was sufficient” to show there weren’t many more new infections, he said. Otherwise “the social cost will be huge and unnecessary”.