Epidemiological characteristics analysis of the first indigenous dengue fever outbreak in Sichuan Province
CHEN Qinchun
LIU Lunguang
CAO Liang
CHEN Jianguo
FENG Kang
CAO Yiou
Abstract：Objective To analyze epidemiological characteristics of Sichuan Province's first indigenous dengue fever outbreak and evaluate the effect of control measures,so as to provide evidence for scientific control strategies.Methods The investigation employed field epidemiology methods,descriptive epidemiology to analyze outbreak characteristics,and a retrospective cohort study to assess the relationship between exposure frequency and merchant infection rates in flower market A.Vector density was monitored using the Breteau idex and double mosquito-net trap methods,and control measures were evaluated.Results 17 indigenous dengue cases were identified(13 clinically diagnosed,4 laboratory-confirmed),all linked to flower market A in Longmatan District,Luzhou.Cases occurred between August 23 and September 29,2019,showing a second-generation transmission pattern.11 cases were market merchants and family members,with spatial spread from the left to the right side of the market.There was a statisticall significant difference in the incidence rate of merchants with different exposure frequencies(χ2=44.17,P＜0.001).The higher the exposure frequency,the greater the risk of dengue fever.Pre-disinfection container indexes were significantly higher in merchant-affected stalls(43.28)compared to unaffected stalls(30.08)(χ2=456.00,P＜0.05).Conclusion This outbreak,the first indigenous dengue fever event in Sichuan,was linked to exposure to flower market A,with merchant infection risk positively correlated with exposure frequency and container index.The outbreak likely originated from virulent vectors introduced from Guangzhou or Yunnan or an imported case from Cambodia.It is recommended to strengthen the training on dengue prevention and control knowledge in medical institutions,and enhance quarantine measures for aquatic plant and mosquito vector monitoring in key places such as flower markets to ensure early detection and control of the outbreak.
Keywords：dengue feverindigenousoutbreakflower marketepidemiologycontrol strategies
Publication Date：2025-12-20
Online Publishing Date：2026-01-09(First online date of this platform, not the publication date of the document)
Pages：5( 726-730 )