Objective To understand the epidemiological characteristics of dengue fever in Wenzhou, Zhejiang province, from 2013 to 2024, and provide evidence for the accurate prevention and control of dengue fever.

Methods The incidence data of dengue fever in Wenzhou from 2013 to 2024 were collected from China Information System for Disease Control and Prevention. Descriptive epidemiological methods were used to analyze the epidemiological characteristics of dengue fever. Excel 2016 was used to collect data on the distributions of the cases, sources of infection and time of diagnosis. Software SPSS 20.0 was used to conduct statistics analysis on gender, age, population, and the interval from onset to diagnosis of the cases.

Results From 2013 to 2024, a total of 398 dengue fever cases were reported in Wenzhou, including 189 imported cases and 209 local cases, and 10 outbreaks were reported. In the reported cases, 248 were men and 150 were women, and the proportion imported cases (71.96%) was higher than that in local cases (53.59%) in men, the difference was significant (χ²=14.260, P<0.001). The median age of the cases was 44 years interquartile range (IQR): 32−55 .The median age was 41 years (IQR: 30.0−50.5) in the imported cases, and 48 years (IQR: 35−59) in the local cases, the difference was significant (Z=19.067, P<0.001). The top three populations of the cases were workers, commercial service providers, the jobless/unemployed, accounting for 63.57% (253 cases). The cases in commercial service providers accounted for the highest proportion (32.28%) in the imported cases, while the cases in workers (28.71%) were the most common in local cases. The population distribution between the imported cases and the local cases showed significant difference (χ²=44.579, P<0.001). The imported cases occurred all the year round with high incidence during June-October, whereas the local cases usually occurred during August- October. The imported cases were reported in 12 counties (districts) , and the local cases were reported in 8 counties (districts) . The median interval from onset to diagnosis of the imported cases was 4 days (IQR:1−7), whereas it was 2 days (IQR:1−4) in the local cases, the difference was significant (Z=6.637, P=0.010).

Conclusion The incidence of dengue fever was characteristized by case importation and obvious seasonality in Wenzhou. There were gender, age, population and disgnosis time specific significant differences between the imported cases and the local cases. It is necessary to strengthen the surveillance for the rapid emergency response to imported cases of dengue fever to reduce the incidence of local dengue fever outbreaks.