ABSTRACT
Objective: To analyze the epidemiological characteristics of an epidemic of coronavirus disease 2019 (COVID-19) caused by occupational exposure in Xining, Qinghai province, from October 17 to November 2, 2021 and provide evidence for the prevention and control of COVID-19 epidemic. Methods: In accordance with the requirements of the COVID-19 prevention and control protocol (eighth edition), epidemiological survey and field response were conducted and throat swabs were collected from the confirmed cases and close contacts. Real time-PCR(RT-PCR) was used to detect severe acute respiratory syndrome coronavirus (SARS-CoV-2) nucleic acid. Gene sequencing was performed for the throat swabs of partial confirmed cases by high throughput sequencing. Results: A total of 11 COVID-19 cases were reported in this epidemic, including 3 cases in a family and 8 cases in medical staff. Nine cases were women, 2 cases were men. The cases in epidemic had 3 generations. The average incubation period was 3.18 day. The infection was mainly occurred in working place. The risk factors included sharing telephone, computer and other office equipment. The initial symptoms were cough (10 cases, 90.97%). Unstandardized taking off protective suit in field epidemiological survey and inappropriate design of waterproof boot cover were the main risk factors for the occupational exposure. The SARS-CoV-2 detected belonged to VOC/Delta variant. Conclusion: This epidemic was caused by occupational exposure. It is suggested to strengthen the field supervision and guide of the wearing of protective suits, improve the design of waterproof boot cover and reduce the contacts of field workers with others.