Abstract: Objective　To investigate the epidemiological characteristics of cross⁃county imported dengue fever cases within Yunnan province in 2023, so as to provide insights into formulation of preventive and control measures for intra⁃provincial spread of dengue fever.  Methods　All data pertaining cross⁃county imported dengue fever cases within Yunnan Province in 2023 were collected, and the temporal, regional and population distributions of the cases were descriptively analyzed.  Results　A total of  1 664 intra⁃provincial cross⁃county imported dengue fever cases were reported in 95 counties (cities, districts) cross 16 profectures (cities) in Yunnan Province in 2023, accounting for 12.34% of total cases in the province. Cross⁃county imported dengue fever cases were predominantly reported during the period between August and October (1 516 cases, 91.11% of total cases), and peaked in September (659 cases), with a single⁃day peak on October 8 (36 cases). During the period from September 4 to 10, five counties (cities) with local dengue fever epidemics, including Jinghong City of Xishuangbanna Dai Autonomous Prefecture, Gengma Dai and Wa Autonomous County of Lincang City, Ruili City of Dehong Dai and Jingpo Autonomous Prefecture, Mengla County of Xishuangbanna Dai Autonomous Prefecture, and Zhenkang County of Lincang City, exported 165 cross⁃county imported dengue fever cases to the rest of the province. Among the 1 644 intra⁃provincial cross⁃county imported dengue fever cases, the male to female ratio was 1.40∶1, and 1 329 cases were at ages of 15 to 55 years (79.87%), with farmers as the predominant occupation (886 cases, 53.25%). The top 5 counties (cities/districts) reporting the highest number of intra⁃provincial cross⁃county imported dengue fever cases included Simao District (266 cases) and Lancang Lahu Autonomous County (118 cases) of Pu'er City, Mengla County (91 cases) and Menghai County (91 cases) of Xishuangbanna Dai Autonomous Prefecture, and Mangshi City (73 cases) of Dehong Dai and Jingpo Autonomous Prefecture, which accounting for 38.40% of total imported cases. These intra⁃provincial cross⁃county imported dengue fever cases originated from 7 counties (cities/districts) in 4 prefectures (cities), including 1 261 cases (76.70%) from Jinghong City of Xishuangbanna Dai Autonomous Prefecture, 224 cases (13.63%) from Ruili City of Dehong Dai and Jingpo Autonomous Prefecture, 103 cases (6.27%) from Gengma Dai and Wa Autonomous County of Lincang City, 31 cases (1.89%) from Mengla County of Xishuangbanna Dai Autonomous Prefecture, 30 cases (1.82%) from Zhenkang County of Lincang City, 10 cases (0.61%) from Cangyuan Wa Autonomous County of Lincang City, and 5 cases (0.30%) from Mohan⁃Boten Economic Cooperation Zone of Kunming City. In addition, local dengue fever epidemics following intra⁃provincial cross⁃county importation of dengue fevers cases in Simao District, Jinggu Dai and Yi Autonomous County, Mangshi City, Longchuan County, and Cangyuan Wa Autonomous County. Conclusions　Farmers and students are high⁃risk populations for intra⁃provincial cross⁃county imported dengue fever cases in Yunnan Province, and health education pertaining personal protection against dengue fever should be strengthened among these high⁃risk populations by governments at all levels. There is a high risk of local outbreak of dengue fever following continuous introduction of intra⁃provincial cross⁃county imported cases. Standardized management of intra⁃provincial cross⁃county imported dengue fever cases should be reinforced to reduce the risk of local epidemics.

Key words: Dengue fever, Imported case, Epidemiological characteristic, Yunnan Province

摘要： 目的　分析2023年云南省登革热省内跨县（市、区）输入病例的流行病学特征，为制定登革热省内扩散防控措施和策略提供参考。方法　收集2023年云南省登革热省内跨县（市、区）输入病例资料，对其报告时间、地区以及人群分布特征进行流行病学描述分析。结果　2023年云南省16个州（市）95个县（市、区）累计报告省内跨县（市、区）输入病例1 664例，占该当年该省登革热病例总数的12.34%（1 664/13 483）。病例报告时间集中于8—10月，该时段共报告1 516例（占91.11%）；9月为报告病例数高峰（659例），10月8日为单日报告病例数高峰（36例）；9月4—10日西双版纳傣族自治州景洪市、勐腊县，临沧市耿马傣族佤族自治县、镇康县以及德宏傣族景颇族自治州瑞丽市5个本地疫情县（市、区）向全省输出跨县（市、区）病例165例。1 664例省内跨县（市、区）输入病例男女性别比为1.40∶1，以15 ~ < 55岁病例数最多（1 329例，占79.87%），职业以农民为主（886例，占53.25%）。省内跨县（市、区）输入病例报告数居前5位的分别是普洱市思茅区（266例）、澜沧拉祜族自治县（118例）、西双版纳傣族自治州勐腊县（91例）、勐海县（91例）和德宏傣族景颇族自治州芒市（73例），上述5个县（市、区）报告输入病例数占输入病例总数的38.40%（639/1 664）。输入病例来源于4个州（市）7个县（市、区），其中景洪市1 261例（占76.70%）、瑞丽市224例（占13.63%）、耿马傣族佤族自治县103例（占6.27%）、西双版纳傣族自治州勐腊县31例（占1.89%）、镇康县30例（占1.82%）、沧源佤族自治县10例（占0.61%）、昆明市磨憨⁃磨丁经济合作区5例（占0.30%）。思茅区、景谷傣族彝族自治县、芒市、陇川县和沧源佤族自治县报告登革热省内跨县（市、区）输入病例后均发生本地疫情。结论　农民和学生是云南省登革热省内扩散防控的重点群体，应加强对这两类人群的健康宣教。在跨县（市、区）输入性病例持续发生后，本地登革热暴发风险较高，故应加强输入病例的规范处置，以降低本地疫情发生风险。

关键词: 登革热, 输入病例, 流行病学特征, 云南省