Study on the prevalence model of asymptomatic covid-19 infection in Chinese
Recently, considerable efforts have been focused on intensifying the screening process for asymptomatic COVID-19 cases in the Chinese Mainland, especially for up to 10 million citizens living in Wuhan City by nucleic acid testing. However, a high percentage of domestic asymptomatic cases did not develop into symptomatic ones, which is abnormal and has drawn considerable public attention. Here, we aimed to investigate the prevalence of COVID-19 infections in the Chinese Mainland from a statistical perspective, as it is of referential significance for other regions. By conservatively assuming a development time lag from pre-symptomatic (i.e. referring to the infected cases were screened prior to the COVID-19 symptom onset) to symptomatic as an incubation time of 5.2 days, our results indicated that 92.5% of those tested in Wuhan City, China and 95.1% of those tested in the Chinese Mainland should have COVID-19 syndrome onset, which was extremely higher than their corresponding practical percentages of 0.8% and 3.0%, respectively. We propose that a certain false positive rate may exist if large-scale nucleic acid screening tests for asymptomatic cases are conducted in common communities with a low incidence rate. Despite adopting relatively high-sensitivity, high-specificity detection kits, we estimated a very low prevalence of COVID-19 infections, ranging from 10−6 to 10−4 in both Wuhan City and the Chinese Mainland. Thus, the prevalence rate of asymptomatic infections in China had been at a very low level. Further, given the lower prevalence of the infection, close examination of the data for false positive results is necessary to minimize social and economic impacts.
Cite this article
Jia, X., Chen, J., Li, L., Jia, N., Jiangtulu, B., Xue, T., Zhang, L., Li, Z., Ye, R. and Wang, B. Modeling the Prevalence of Asymptomatic COVID-19 Infections in the Chinese Mainland. The Innovation 1 (2), 100026 (2020). doi: 10.1016/j.xinn.2020.100026