[Epidemiological characteristics of dengue fever outbreaks in China, 2015-2018]

Objective: To analyze the epidemiological characteristics of outbreaks of dengue fever in China from 2015 to 2018, and provide evidence for the prevention and control of dengue fever. Methods: We extracted the incidence data of dengue fever from China Disease Prevention and Control Information System, Public Health Emergency Reporting Management Information System and Vector Biological Monitoring System, and explored the epidemiological characteristics of the outbreaks in the past four years. Excel 2010 software and SPSS 20.0 software were used for data processing and analysis, ArcGIS 10.5 software was used for mapping. Results: A total of 111 outbreaks of dengue fever were reported nationwide from 2015 to 2018, involving 12 490 cases, accounting for 73.7% of the total cases in China. These outbreaks occurred in 85 counties and districts of 4 provinces, namely Guangdong (77 outbreaks), Yunnan (14 outbreaks), Zhejiang (8 outbreaks) and Fujian (8 outbreaks). The outbreaks occurred during May-November. Small-scale outbreaks with no more than 10 cases ended within 30 days (28/34, 82.4%) and larger-scale outbreaks lasted for several months. Dengue virus type 1 and type 2 were the main epidemic pathogens of dengue fever outbreaks in China. The outbreaks mainly occurred in areas with high population density and poor sanitary environment. There were significant differences in the age and occupational composition of the cases in the main outbreak provinces. Conclusions: Outbreaks of dengue fever can been seen in more areas in China, even in high latitudes areas. The epidemiologic characteristics of the outbreaks were different among provinces, showing as port type, rural type and urban type. Each province should adjust the control strategies accordingly.