Abstract: Objective To analyze the epidemiological and etiological detection characteristics of measles in Heze City from 2004 to 2023,and provide data support for eliminating measles. Methods Statistical and descriptive analysis was conducted on the epidemiological characteristics and etiological detection results of measles cases reported in Heze City from 2004 to 2023. Results From 2004 to 2023,3 745 measles cases were reported in Heze. Taking every five years as a statistical period,the highest number of cases in 2004 to 2008 was 2 213,with an average annual incidence rate of 5.43/100 000,the lowest number in 2019 to 2023 was only 22 cases,with an average annual incidence rate of 0.05/100 000. The incidence of measles was mainly in winter and spring,and the peak period was April to May from 2004 to 2013,the peak period was January to March from 2014 to 2018. From 2019 to 2023,due to the low incidence of cases,there were no obvious seasonal characteristics of measles. The incidence of measles in each county ranged from 0 to 32.31/100 000,and the difference was statistically significant（χ²=731.020,P<0.05）. The incidence ratio of male to female was 1.79 ∶ 1,with the majority of cases being those without a history of immunity or those with unknown immunity,accounting for 52.6%（806/1 532） and 32.4%（496/1 532）,respectively. From 2004 to 2018,the incidence of measles showed a "bidirectional shift" trend in age composition,constituent ratio of incidence in age group 0-<8 months increasing from 11.97%（265/2 213） to 25.74%（165/641）,and constituent ratio of incidence in age group ≥20 years increasing from 13.06%（289/2 213） to 33.85%（217/641）. A total of 576 etiological detection samples were collected in Heze from 2013 to 2023,of which 76 were positive for measles nucleic acid. 47 measles virus strains were isolated from positive measles nucleic acid samples,all of which were H1 genotype. Conclusion The incidence rate of measles in Heze City showed a downward trend from 2004 to 2023,especially after 2017,approaching or achieving measles elimination goals. However,due to the severe global measles incidence situation in recent years,the incidence rate continued to rise,which became a threat to consolidate measles prevention and control. The future work should focus on increasing the monitoring of mobile workers and foreign humans,insisting on carrying out high quality leak detection and vaccination work,improving the sensitivity of the surveillance system,improving the level of population immunity,and preventing the spread of imported wild viruses.

Key words: Measles, Incidence rate, Epidemiological characteristics, Etiological detection, Prevention and control