甲流感疫情时空聚集性的GIS分析

2009年肆虐全球的甲流感疫情是由一种突变的猪流感病毒引发的流感,故又被称为猪流感。自2009年5月11日发现首例甲流感病例传入我国以来,在短短几个月的时间里,疫情迅速蔓延并呈现全国大爆发的态势。深圳因地理位置特殊,流动人口众多,一直是我国流行病的高发地区。本文以深圳市为例,对2009年5月26日至2009年11月15日间通过传染病疫情信息网络直报系统所上报的甲型H1N1流感确诊病例,分别依据患者的性别、年龄、职业等属性进行了统计,同时以日发病数为基本单位对这期间的甲流感疫情进行了时序与特征分析;并将病例数据输入地理信息系统进行地理空间定位,选取病例患者的家庭住址作为地理空间定位的基本单元,利用回顾性时空重排扫描统计量的方法对这期间深圳市的甲流感疫情进行时空聚集性分析。结果显示,深圳市的甲流感疫情的时空聚集性重点表现在9月份上旬与香港接壤的南部地区,对深圳市疫情的防控要重点布置在与香港往来的几个通关口岸处。

Space-time Cluster Detection of Pandemic H1N1 Influenza A Using GIS

The influenza A（H1N1） pandemic was root in the gene mutation of swine,so it is also called ＂swine influenza＂.Since the introduction of the first case of H1N1 in China,the epidemic had been rapidly spreading over most provinces of the country in several months and would present a situation of large broken out.The paper analyzed the pandemic H1N1 influenza A in Shenzhen,China during May 26,2009 to November 15,2009.The data of cases rooted in the direct network reporting system for infectious diseases.First,the statistic cases were analyzed according to gender,age and vocation of the sufferers,which shows that the age of sufferers is mainly clustered in the rank of 10-20,more than half of the total cases,and the vocation which has the most infectors is student.Then,temporal distribution in the unit of daily cases was analyzed.The morbidity had been in a relative low level in the beginning 3 months.It suddenly increased rapidly in September and reached the peak on September 6th 2009.That＇s because early September is the time that students got back to school,the mutual infect among students led to the rapid increase of H1N1 influenza A cases.Finally,the data of cases was processed by GIS.The sufferers＇ home addresses were selected as the basic units of geo-coding and google earth tool was used to find the longitude and latitude of each sufferer.The retrospective space-time permutation scan statistic was employed to detect the space-time clusters.The longest incubation period of 7 days was chosen as the maximum temporal cluster size and the maximum spatial cluster size is defined 10 kilometers,approximately equal to the north-south distance of central Shenzhen city.The result shows that the space-time clusters of H1N1 influenza A in Shenzhen City are mainly in the northern areas which border with Hong Kong during early September.The come-and-go between Shenzhen and Hong Kong are very frequent,which caused that the epidemic in Hong Kong affect that in Shenzhen a lot.Thus,the government should enhance the control of virus in the customs between Shenzhen and Hong Kong.