Abstract：Objective To learn the epidemiological characteristics of coronavirus disease 2019(COVID-19)clusters in Nanning,Guangxi Province,so as to provide reference for the prevention and control of COVID-19. Methods The data of COVID-19 clusters from January to February,2020 in Nanning were collected through the Public Emergency Response System of National CDC. Descriptive epidemiological analysis were conducted to analyze the time,space and population distribution, source of infection,transmission chain, ways of detection and the scale of clusters. Results Eleven clusters were reported,with 36 confirmed cases and 293 exposed persons. The average attack rate was 12.29%. There were ten family clusters. The epidemic scale was small,with an average of 3.27 cases. The onset of cases peaked on January 23,while the reporting time was mainly from February 10 to February 18. The cases were distributed in two cities and one county. The attack rate of Qingxiu District and Xixiangtang District was 16.95%,which was higher than 5.17% of Mashan County(p<0.05). The recurrence rate of family contacts was 25.42%,which was higher than that of other ways of contacts(p<0.05). Of eleven clusters,nine were caused by imported cases or related cases;five developed secondary cases or above,and the median interval between the first and secondary cases was three days. Conclusions The COVID-19 clusters in Nanning occurred mainly in families with small scales and most were caused by imported cases. The majority of the cases were reported during mid February. The attack rate in urban areas was higher than that in rural areas.
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