Epidemiological investigation of an outbreak of coronavirus disease 2019 in Dalian, Liaoning, July–August, 2020

  Objective  To understand the epidemiological characteristics of an outbreak of coronavirus disease 2019 (COVID-19) in Dalian, Liaoning, July-August, 2020, and provide reference for the prevention and control of COVID-19.

  Methods  A descriptive analysis was conducted on the time, spatial and population distributions and the detection ways of COVID-19 cases.

  Results  From July 22 to August 5, 2020, a total of 118 cases of confirmed COVID-19 cases and asymptomatic cases were reported in Dalian, including 58 men and 60 women. The age of the cases ranged from 1 month to 73 years. There were 92 confirmed cases. The first case occurred on 9 July and the last case occurred on 5 August. The onset time of the case in a food company was earlier than that of a case outside the company. Up to 81.36% of the cases were reported in high-risk areas of a food company and Dalian Bay Street, and 95.76% of the cases were detected through close contact and community screening.

  Conclusion  The epidemic of COVID-19 occurred in Dalian was related to the processing of frozen seafood products. The epidemic control was timely and effective, and there was no secondary community transmission.