2015—2018年南宁市登革热媒介伊蚊监测结果分析和登革热风险评估

Analysis of surveillance results of dengue vector Aedes mosquitoes and assessment the risk of dengue fever in Nanning in 2015-2018

目的分析南宁市伊蚊种群、密度、分布、季节变化趋势及其影响因素,评估登革热发生和流行的风险。方法收集南宁市各监测点登革热媒介伊蚊监测数据进行描述性统计分析,参照国家登革热风险评估标准进行南宁市登革热风险评估。结果2015年5月至2018年4月期间,南宁市的伊蚊均为白纹伊蚊,未发现埃及伊蚊,均未检出登革热病毒。每年3月,伊蚊幼虫、成虫的密度逐渐升高,4—10月为全年较高时段、6—8月达最高水平,在11月至次年3月,为密度较低时段;幼虫、成虫均可越冬。不同月份、年份的伊蚊密度差异均有统计学意义(P<0.005)。伊蚊密度与平均气温、最低气温、最高气温、日照时间、相对湿度、降雨量存在正相关关系,与平均气压存在负相关关系,回归分析均有统计学意义(P<0.005)。伊蚊幼虫密度由高到低的场所依次为花鸟市场、废品收购站、居民区、公园、医院、工地,成蚊密度依次为公园、居民区、医院、废品收购站和工地。结论南宁市白纹伊蚊分布广泛,6—8月期间登革热输入和本地传播的风险较高,应加强登革热的预测预警,采取有效防控措施,防止发生流行。

Objectiv To analyze the population,density,distribution,and the seasonal variation of Aedes mosquitoes and their influencing factors in order to assess the morbidity and endemic of dengue fever in Nanning.Methods The surveillance data of Aedes mosquitoes in Nanning from 2015 to 2018 were collected and analyzed with descriptive statistical method,and the risk of dengue fever was assessed under the guideline of the national dengue risk assessment standards.Results From May 2015 to April 2018,only Aedes albopictus was found,and all of the mosquito samples were negative on the test for dengue fever virus in Nanning.The density of the larva and adult Aedes was increased in March and reached the highest level between June to October;the level went down between November to March in the next year.The larva and adult Aedes were able to survive during the winter.The difference between the density of Aedes mosquitoes in different months and years was statistically significant(P<0.005).There was a positive correlation between the density of mosquito and the average temperature,daily minimum temperature,daily maximum temperature,daily sunshine duration,relative humidity,and rainfall,respectively(P<0.005).Meanwhile,there was a negative correlation between the density and the average pressure,and the regression analysis was statistically significant(P<0.005).The highest density of the larvae mosquito was found in the flower and bird markets,followed by the waste collection stations,the residential areas,parks,hospitals and the construction sites.The highest density of the adult mosquito was found in the parks,and followed by the residential areas,hospitals,the waste collection stations and the construction sites.Conclusion Aedes albopictus is widely distributed in Nanning.From June to August,the risk of importing and local transmission of dengue fever is high.Monitoring and early warning of dengue fever should be strengthened and the preventive measures should be taken in order to prevent the outbreak.