Abstract:

Objective: To investigate the epidemiological characteristics of dengue fever in Nantong City, Jiangsu Province, China, so as to provide a reference for formulating appropriate prevention and control strategies. Methods: The data of dengue fever cases in Nantong City in 2014-2022 were collected from the China Information System for Disease Control and Prevention and epidemiological investigation reports, and the descriptive epidemiological method was used to perform statistical analyses of the temporal, regional, and population distribution, imported sources, disease onset, and medical treatment of the cases. ArcGIS 10.8 software was used to visualize the regional distribution of the cases. SPSS 22.0 software was used to perform the Shapiro-Wilk test to investigate the normality of the interval time from disease onset to confirmed diagnosis and the interval time from arriving in Nantong City to confirmed diagnosis. Results: In 2014-2022, a total of 52 dengue fever cases were reported in Nantong City, with a mean annual incidence rate of 0.08/100 000, and the highest incidence rate of 0.51/100 000 was observed in 2019. The peak of dengue fever was observed in June to September, with 37 cases accounting for 71.15%. Cases were reported in all seven counties (cities/districts), among which Haimen District reported 19 cases, accounting for 36.55%. The age group of 40- years showed the highest number of 21 cases, which accounted for 40.38%. The male/female ratio was 9.4∶1. As for occupation, most of the patients were migrant workers, with 30 cases accounting for 57.69%. All cases were imported from abroad, mainly Southeast Asia, with 47 cases accounting for 90.38%. The majority of the cases were firstly diagnosed in tertiary medical institutions, with 28 cases accounting for 53.85%. For these 52 cases, the median time interval from disease onset to confirmed diagnosis was 6.0 days. A total of 20 cases were diagnosed in the viremia stage, accounting for 41.67%. Conclusions: The epidemic situation of dengue fever in Nantong City in 2014-2022 shows obvious imported and seasonal characteristics. It is suggested that inbound individuals from Southeast Asia should be regarded as the key population for quarantine and follow-up observation in June to September each year, and it is also recommended to enhance the surveillance and control of mosquito vectors.

Key words: Dengue fever, Imported case, Distribution, Trend, Epidemiological characteristic

摘要：

目的: 了解南通市登革热流行特征，为制定适宜的防控策略提供参考依据。方法: 从中国疾病预防控制信息系统和流行病学调查报告中收集2014－2022年南通市登革热病例资料，采用描述性流行病学方法对病例的三间分布、输入来源和发病就诊情况进行统计分析。采用ArcGIS 10.8软件绘图，对病例的地区分布进行可视化展示。采用SPSS 22.0软件做Shapiro-Wilk检验，检验发病至确诊的间隔时间和返回南通市至确诊的间隔时间正态性。结果: 2014－2022年南通市累计报告52例登革热病例，年均发病率为0.08/10万，2019年发病率最高，为0.51/10万。发病高峰期为6－9月，共37例，占71.15%。全市7个县（市、区）均有病例报告，海门区病例数最多，报告19例，占36.55%。40~岁年龄组病例最多，为21例（40.38%）。男女性别比例为9.4∶1。职业以务工人员为主，为30例（57.69%）。病例均为境外输入，其中东南亚地区输入最多，为47例（90.38%）。首诊以三级医疗机构为主，为28例（53.85%）。52例病例发病至确诊的时间间隔中位数为6.0 d。病毒血症期确诊20例，占41.67%。结论: 2014－2022年南通市登革热疫情具有明显的输入性和季节性特征，建议每年6－9月将来自东南亚的入境人员作为检疫和随访观察的重点人群，并加强蚊媒监测和控制。

关键词: 登革热, 输入病例, 分布, 趋势, 流行特征