2019—2021年广州市登革热媒介白纹伊蚊监测分析

Surveillance on dengue vector Aedes albopictus in Guangzhou from 2019 to 2021

目的了解广州市登革热媒介白纹伊蚊种群密度和季节消长的动态变化,评估广州市白纹伊蚊传染病的传播风险,为登革热的防控策略制定提供科学依据。方法采用布雷图指数(BI)、标准间指数(SSI)、诱蚊诱卵器指数(MOI)、成蚊密度(ADI),于2019—2021年对广州市11个行政区逐月开展白纹伊蚊密度监测,并按不同月份、行政区进行汇总分析。结果2019—2021年BI为2.90~4.50,SSI为0.73~0.96,MOI为7.53~9.29,ADI为2.94~3.38;除2020年MOI低于2021年外,全市平均BI、SSI、ADI均呈逐年下降趋势;4个白纹伊蚊密度指标不同年份差异有统计学意义(P<0.01);各指标4—9月逐渐上升,9月后逐渐下降;除2级比例外,其他风险等级比例差异均有统计学意义(P<0.05);2021年2级和3级风险累积比较高的行政区较少,2019—2021年天河区、白云区、南沙区和荔湾区2级和3级风险累积比例整体较低。结论广州市白纹伊蚊密度在2019—2021年每年的4月已处于相对较高水平,因此孳生地清除措施应早于4月开始;5—9月是广州市白纹伊蚊密度的高峰期,传播登革热的风险较大,需提高市民防蚊、灭蚊意识,并在雨季和夏季来临前清除蚊媒孳生地以降低白纹伊蚊密度。

Objective To master the population density and seasonal fluctuation of dengue vector Aedes albopictus in Guangzhou and to evaluate the transmission risk of dengue fever,providing a scientific basis for the rational formulation of dengue fever prevention and control strategies.Methods Breitu index(BI),standard space index(SSI),mosquito trapping index(MOI)and adult mosquito density index(ADI)were used to monitor the density of Aedes albopictus month by month in 11 administrative districts of Guangzhou from 2019 to 2021.Results Breteau index(BI),standard space index(SSI),mosquito oviposition index(MOI)and adult mosquito density index(ADI)ranged from 2.90 to 4.50,0.73 to 0.96,7.53 to 9.29,and 2.94 to 3.38 from 2019 to 2021.With the exception of a lower MOI in 2020 than in 2021,the average BI,SSI and ADI in the city decreased year-on-year.There were statistically significant differences among the four density indexes of Aedes albopictus in different years(P<0.01).Each index gradually increased from April to September,and declined gradually after September.There was significant difference in the proportions of other risk grades except grade 2(P<0.05).There were few regions with a higher cumulative risk in 2021.The overall level 2 and 3 risk accumulation ratio in Tianhe District,Baiyun District,Nansha District and Liwan District in 2019—2021 was relatively low.Conclusion The density of Aedes albopictus in Guangzhou was relatively high in April,so the elimination of breeding sites should be carried out earlier than April.The peak period of Aedes albopictus density is from May to September in Guangzhou,and the risk of transmission of dengue fever is high.It is necessary to enhance public awareness of mosquito control and eliminate mosquito breeding grounds before the rainy season and summer to reduce Aedes albopictus density.