Saxena Rekha, Nagpal B N, Singh V P, Srivastava Aruna, Dev Vas, Sharma M C, Gupta H P, Tomar Arvind Singh, Sharma Shashi, Gupta Sanjeev Kumar
National Institute of Malaria Research, Dwarka, New Delhi, India.
J Vector Borne Dis. 2014 Sep;51(3):211-5.
BACKGROUND & OBJECTIVES: An alarming rate of deforestation has been reported from Sonitpur district of Assam, India therefore, a study was initiated during 2009 using remote sensing (RS) to assess deforested areas in the district and to study the impact on malaria vectors in order to formulate appropriate control strategy.
RS imageries of 2000 and 2009 were used to assess deforested areas in the selected district. Entomological data were collected in four surveys during 2009-2011. The data were analyzed statistically using test of single proportions (χ 2 ) and pair-wise comparison. Vector incrimination was done using enzyme-linked immunosorbent assay (ELISA) and entomological inoculation rate (EIR) was calculated to estimate transmission intensity.
The deforested areas were identified in north-western parts of Sonitpur district falling in Dhekiajuli Primary Health Centre (PHC). The forest cover of the PHC decreased >50% during 2000-2009. Five species of anopheline vectors were collected. Anopheles minimus sensu lato (s.l.) was collected least abundantly while An. culicifacies s.l. prevailed most abundantly and significant difference was observed between proportions of the collected vector species. Pair-wise comparison between An. culicifacies s.l. and An. minimus s.l. was also found statistically significant indicating that An. culicifacies s.l. is establishing its population in deforested areas. An. culicifacies s.l. was found ELISA positive and EIR was measured as 4.8 during transmission season.
An. culicifacies s.l. replaced An. minimus s.l., the vector of malaria in northeast India and was found ELISA positive, therefore could have possible role in malaria transmission in the deforested areas of the district.
据报道，印度阿萨姆邦索尼特布尔地区的森林砍伐率令人担忧，因此，于2009年启动了一项研究，利用遥感技术（RS）评估该地区的森林砍伐面积，并研究其对疟疾媒介的影响，以便制定适当的控制策略。
利用2000年和2009年的RS影像评估选定地区的森林砍伐面积。在2009 - 2011年期间进行了四次调查收集昆虫学数据。使用单比例检验（χ²）和成对比较对数据进行统计分析。采用酶联免疫吸附测定（ELISA）进行媒介鉴定，并计算昆虫学接种率（EIR）以估计传播强度。
在索尼特布尔地区西北部属于德凯亚朱利初级卫生保健中心（PHC）的区域发现了森林砍伐区域。该初级卫生保健中心的森林覆盖率在2000 - 2009年期间下降了超过50%。收集到了五种按蚊媒介。微小按蚊复合组（Anopheles minimus sensu lato, s.l.）的采集数量最少，而嗜人按蚊复合组（An. culicifacies s.l.）的数量最多，且所收集的媒介种类比例之间存在显著差异。嗜人按蚊复合组和微小按蚊复合组之间的成对比较也具有统计学意义，表明嗜人按蚊复合组正在砍伐森林地区建立种群。嗜人按蚊复合组经ELISA检测呈阳性，在传播季节测得的EIR为4.8。
嗜人按蚊复合组取代了印度东北部的疟疾媒介微小按蚊复合组，且经ELISA检测呈阳性，因此可能在该地区森林砍伐区域的疟疾传播中发挥作用。
