ObjectiveThe duties, discipline cross-complementation, and work stress of professional staff during the COVID-19 pandemic are analyzed and summarized to provide a scientific basis for workforce allocation and reserve in respect of infectious disease prevention and control in the disease prevention and control (DPC) system.MethodThe cross-sectional survey was made in April-May 2021 on professional staff in the Beijing DPC system by way of typical + cluster sampling. A total of 1,086 staff were surveyed via electronic questionnaire, which was independently designed by the Study Group and involves three dimensions, i.e., General Information, Working Intensity & Satisfaction, and Need for Key Capacity Building. This paper focuses on the former two dimensions: General Information, Working Intensity, and Satisfaction. The information collected is stored in a database built with Microsoft Excel 2010 and analyzed statistically with SPSS 22.0. The results are expressed in absolute quantities and proportions. Assuming that the overload of work stress is brought by incremental duties and cross-discipline tasks, a binary logistic regression model is constructed.ResultsAmong the 1086 staff surveyed, 1032 staff were engaged in COVID-19 prevention and control works, and they can be roughly divided into two groups by their disciplines: Public Health and Preventive Medicine (hereinafter referred to P, 637 staff, as 61.72%) and Non-Public Health and Preventive Medicine (hereinafter referred to N-P, 395 staff, as 38.28%). During the COVID-19 pandemic, the 1,032 staff assumed a total of 2239 duties, that is, 2.17 per person (PP), or 2.45 PP for the P group and 1.72 PP for the N-P group. As to four categories of duties, i.e., Spot Epidemiological Investigation and Sampling, Information Management and Analysis, On-site Disposal, Prevention, Control Guidance, and Publicity, the P group accounts for 76.14, 78.50, 74.74, and 57.66%, respectively, while the N-P group accounts for 23.86, 21.50, 25.26, and 42.34%, respectively. Obviously, the former proportions are higher than the latter proportions. The situation is the opposite of the Sample Detection and Other Works, where the P group accounts for 25.00 and 31.33%, respectively, while the N-P group accounts for 75.00 and 68.67%, respectively. The analysis of work stress reveals that the P group and N-P group have similar proportions in view of full load work stress, being 48.67 and 50.13%, respectively, and the P group shows a proportion of 34.38% in view of overload work stress, apparently higher than the N-P group (24.05%). Moreover, both groups indicate their work stresses are higher than the pre-COVID-19 period levels. According to the analysis of work stress factors, the duty quantity and cross-discipline tasks are statistically positively correlated with the probability of overload work stress.ConclusionThe front-line staff in the DPC system involved in the COVID-19 prevention and control primarily fall in the category of Public Health and Preventive Medicine discipline. The P group assumes the most duties, and the N-P group serves as an important cross-complement. The study results indicate that the prevention and control of same-scale epidemic require the duty post setting at least twice than usual. As to workforce recruitment, allocation, and reserve in respect of the DPC system, two solutions are optional: less addition of P staff, or more addition of N-P staff. A balance between P and N-P staff that enables the personnel composition to accommodate both routine DPC and unexpected epidemic needs to be further discussed.