Abstract：Objective To investigate the epidemiological features of spread of SARS-CoV-2 Delta variant in a farmers' market so as to provide a scientific basis for prevention and control of the epidemic caused by SARS-CoV-2 Delta variant in the people-gathering places. Methods Descriptive epidemiological methods were used to describe the epidemiological characteristics of the SARS-CoV-2 epidemic. The incubation period of the cases and time-varying reproduction numbers were estimated and calculated. Results From December 7 to 20, 2021, a total of 122 confirmed cases of SARS-CoV-2 infection and 104 asymptomatic infected persons were cumulatively identified in the epidemic. The average age was 49.53 years old, and the ratio of male to female was 0.74:1. The occupations of the cases were mainly individual vendors (30.97%) and housewives (16.81%). 9 townships/streets were involved in the epidemic, mainly occurring in Caoe Street (82.30%) and Baiguan Street (5.75%). The median incubation period of SARS-CoV-2 among the cases in the epidemic was 4 days (with a range of 2-12 days). The time-varying reproduction number was 4.6 during the peak period of the epidemic, and then showed a constantly downward trend, declining to below 1 within 13 days after the occurrence of the epidemic. The epidemic spread in turn among individual vendors, customers and customers' families. The number of SARS-CoV-2 infection cases decreased to 0 within 13 days (from December 7 to 20) since the discovery of the local outbreak, and the main discovery methods were population screenings based on centralized quarantine (45.13%) and self-quarantine at home (39.38%). Conclusion SARS-CoV-2 Delta variant spread very fast in the farmers' market, suggesting that we should quickly identify and isolate the risk population so as to control the spread of the epidemic.
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2024, Vol. 31 
