Analysis of COVID-19 clustered outbreaks in Zhengzhou, China

ABSTRACT

The aim of this study was to understand epidemiological characteristics of aggravated epidemic situation of COVID-19 pneumonia in Zhengzhou and provide evidence for effective prevention and control measures., The data were collated and analyzed using epidemiological description methods. There was a total of 34 clustered outbreaks. Family (ethnic) group accounted for 85.29% (29/34), international travel group accounted for 5.88% (2/34), company group accounted for 2.94% (1/34), hospital group accounted for 5.88% (2/34). The number of clustered cases accounted for 61.15% (96/157) of the reported confirmed cases in Zhengzhou. 58.82% of the clustered outbreaks were related to other provinces and cities (including Wuhan). Among the clustered outbreaks, one of the follow-up cases occurred earlier than the indicated case, one occurred simultaneously with the indicated case. This study indicates that clustered epidemic of Zhengzhou is dominated by families, and it is necessary to implement centralized medical observation for all close contacts of cases. After resumption work and production, we should implement various related policies and be vigilant against the occurrence of cluster epidemics in enterprises and institutions. The subsequent cases occur earlier or at the same time as the indicated cases, suggesting that the incubation period is contagious.