Opinion | Time for China to align with global practice in counting coronavirus cases
- Since February, China’s coronavirus tally of ‘confirmed’ cases has not included positive patients who are asymptomatic or presymptomatic
- Data shows that asymptomatic cases make up a significant percentage of the total number of positive patients and they can spread Covid-19
The seemingly contradictory report relates to China’s unique definition of Covid-19 confirmed cases, which excludes positive patients who are asymptomatic or presymptomatic. The 178 people who tested positive are not counted as confirmed cases, although some will be included later when they show symptoms.
China began to release figures counting asymptomatic cases from April. But they are not counted as confirmed cases unless they develop symptoms or lung imaging is abnormal.
By late February, the South China Morning Post had learned about a third of positive cases were silent carriers or presymptomatic patients. But it is unclear how many asymptomatic cases China has had so far because accumulated figures were never released.
Chinese officials argued early in the pandemic that the number of true asymptomatic cases was small and “there was no evidence” they could spread the disease.