Study On Density Monitoring And Prevention And Control Measures Of Dengue Vector Aedes Albopictus In Guangzhou

ObjectiveTo understand the current situation on density monitoring and prevention and control measures of dengue vector Aedes albopictus in Guangzhou after the outbreak of dengue fever,and find out the problems of mosquito vector density monitoring and disposal.In order to put forward the suggestions of optimizing mosquito vector density monitoring and killing mosquitoes in Guangzhou,and provide a scientific basis for further control of mosquito vector density and prevention and control of dengue fever.MethodsDengue vector density monitoring data of Aedes albopictus in Guangzhou from 2016 to 2018 were collected systematically,including Breteau index(BI)、House index(HI)、Container index(CI)、Standard Space index(SSI)、Mosquito Ovitrap Index(MOI)and Adult-mosquito Density Index(ADI).Descriptive statistical methods were used to analyze the dengue vector density of Aedes albopictus in Guangzhou from 2016 to 2018.Positive rate and risk grade of transmission were tested by chi-square tests.The risk level monitored by the city emergency team and the municipal districts at the same time and location were compared by matched?~2 tests.Spearman rank correlation analysis was used to analyze the correlation between the densities of Aedes albopictus.Qualitative interviews were conducted among emergency teams and CDC personnel responsible for mosquito vector-related work,and documents were analyzed based on thematic frameworks.The software used includes WPS Excel,SPSS 20.0 and NVivo 11.Results1、From 2016 to 2018,BI,HI and CI of Guangzhou residents were3.70,3.16 and 8.16 respectively;SSI and CI of external environment were 0.58 and 18.13 respectively;MOI was 7.30;ADI was 2.33.2、From 2016 to 2018,the density index of Aedes albopictus in Guangzhou showed the seasonal regularity of high in summer and autumn(June-November),low in winter and spring(January-May and December),rising gradually from February,peaking in May-October and declining gradually after October.3、MOI in Liwan,Huangpu,Panyu and Zengcheng districts during the epidemic period of dengue fever(July-November)indicated moderate risk of transmission;MOI in enterprises and institutions suggested moderate risk of transmission.4、BI,SSI,MOI and ADI had a strong correlation.The correlation coefficients were 0.93(SSI and ADI),0.89(MOI and ADI),0.87(BI and ADI),0.87(BI and MOI),0.86(BI and SSI),0.84(SSI and MOI),respectively.5、The risk-free rate of Aedes albopictus density monitoring sites in Guangzhou from 2016 to 2018 was 57.52%.The low,moderate and high risk components were 20.17%,13.52%and 8.80%,respectively.6、The risk level monitored by the city emergency team at the same time and location was higher than that monitored by the municipal districts.7、A total of 15 interviews were conducted with 33 participants,including 29 males and 3 females,with an average age of(33.48+8.34)years.8、The daily mosquito vector surveillance had some problems,such as difficulty in entering the household,heavy workload and insufficient manpower.It was suggested to provide a unified conversion area method and clean up mosquito breeding sites in different environments.9、The awareness of mosquito vector control was not enough,and the attitude of each street to cooperate with the work of killing was inconsistent.Emergency team personnel were too mobile and lack of professionalism.It was suggested that in the process of dealing with the epidemic situation,various parts should communicate more and improve the operational ability of the killing team.Conclusions1、The density of mosquito vectors during the epidemic period of dengue fever in Guangzhou was higher than that in the non-epidemic period.2、The areas with high density index of residential areas were concentrated in the suburbs and urban-rural fringe of Guangzhou.The areas with high density index of external environment are concentrated in the urban-rural fringe and the old urban areas of Guangzhou.3、In the monitoring of Aedes albopictus,the city emergency team and the monitoring of Aedes albopictus at all district levels can complement each other.4、In the daily monitoring process,we should make comprehensive reference to BI,SSI,MOI and ADI to continuously carry out mosquito vector monitoring.We can understand the growth and decline of dengue vector density in Guangzhou through mosquito vector density index,and provide guidance for mosquito vector control.5、To comprehensively carry out mosquito vector control and rational use of insecticides.We should strengthen the professionalism of the personnel of the emergency mosquito vector killing team and ensure the standardization of the technology.6、The prevention and control of mosquito vectors need the cooperation of various departments,strengthen the publicity and education of dengue fever,and encourage residents to actively participate in the activities of clearing water,turning pots and pouring pots,so as to reduce the breeding environment of mosquito vectors.