Abstract: Objective: To analyze the epidemiological characteristics of new leprosy at different control periods in Gansu Province from 2001 to 2020, and provide a reference for leprosy prevention and control strategies and measures. Methods: The data of new leprosy in Gansu Province during three different prevention and control stages: the “2001-2005 Leprosy Prevention and Control Strategy” (the 10th Five-Year Plan period), the “2006-2010 Leprosy Prevention and Control Strategy” (the 11th Five-Year Plan period), and the “Gansu Province Leprosy Hazard Elimination Plan (2011-2020)” (the ten-year leprosy risk elimination period) were retrospective analyzed. Results: From 2001 to 2020, a total of 117 newly detected leprosy cases in different control periods were reported in Gansu Province, with an average detection rate of 0.022/105 . The detection rate showed a significant downward trend (AAPC=-3.276，P<0.05), and the local distribution was serrated. The average detection rate in the the 10th Five-Year Plan period was significantly higher than that in the the 11th Five-Year Plan period (Z=-2.227, P=0.026) , 2011-2015 (Z=-2.552,P=0.008）and 2016-2020（Z=-2.207，P=0.032）periods. 3.42% patients were children, and they have been found in different control period. The age group of 15-40 years old showed a significant downward trend (χ2trend=10.583, P=0.001), while the age group 41-64 years old showed an significant upward trend (χ2trend=6.897, P=0.009), and there was no significant change in other age groups. In terms of the concrete discovery methods, outpatient discovery in dermatology department increased significantly (χ2trend=16.108, P=0.000), and there was no significant change in other discovery methods. The rate of gradeⅡdeformity was 64.0% during the ten-year leprosy risk elimination period, which was significantly higher than that in the other two stages (χ2=15.875, P<0.05). Conclusion: The overall incidence of leprosy in Gansu Province during different control periods from 2001 to 2020 showed a significant downward trend, but new cases of aging, long delay period, and high disability of new cases are still prominent. It is necessary to continue to strengthen early detection of leprosy.

Key words: leprosy, news cases, different control periods, epidemiological characteristics