Anopheles gambiae: historical population decline associated with regional distribution of insecticide-treated bed nets in western Nyanza Province, Kenya.
Anopheles gambiae: historical population decline associated with regional distribution of insecticide-treated bed nets in western Nyanza Province, Kenya.
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DOI：
10.1186/1475-2875-9-62
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发表时间：
2010-02-26
期刊：
影响因子：
3
通讯作者：
Walker ED
中科院分区：
文献类型：
--
作者：
Bayoh MN;Mathias DK;Odiere MR;Mutuku FM;Kamau L;Gimnig JE;Vulule JM;Hawley WA;Hamel MJ;Walker ED
肯尼亚尼安萨省西部的两个邻近社区阿森博经杀虫剂处理的蚊帐覆盖率较高，而塞梅的覆盖率较低；随后，随着肯尼亚国家疟疾计划的推出，塞梅扩大了蚊帐的覆盖范围；提供了一个自然实验，用于量化该大流行地区两种主要疟疾病媒相对丰度的变化。两者均属于冈比亚按蚊 sensu lato (s.l.) 物种复合体，即冈比亚按蚊 sensu stricto (s.s.) 和阿拉伯按蚊。从历史上看，前一个物种在雌性室内休息群体中占主导地位。冈比亚 A. gambiae s.s. 成虫相对丰度数据从房屋内部取样的 A. 和 A. arabiensis 是从 1970 年至 2002 年肯尼亚基苏木以西至 Asembo 地区的文献中获得的。距市区50公里。从阿森博（由于实施了受管理的蚊帐分发计划，蚊帐使用率很高）向东到塞梅（没有实施蚊帐计划）建立了一个采样样带。 A. gambiae s.l. 成虫2003年至2009年，从样带沿线的房屋内部取样，并从附近水生生境采集了幼虫，提供了近40年来这两个物种相对丰度的数据。 A. gambiae s.s. 的相对比例通过聚合酶链式反应方法鉴定物种，确定了每个阶段的 A. arabiensis 和 A. arabiensis。家庭蚊帐拥有量是通过蚊子收集期间的调查来衡量的。冈比亚疟原虫血液宿主选择、产次率和恶性疟原虫感染率数据和 A. arabiensis 是从 2005 年来自 Asembo 和 Seme 的样品中获得的。 1970 年至 1998 年间，室内收藏的成年女性占主导地位（约 85%）。从 1999 年开始，冈比亚 A. gambiae s.s 相对于 A. arabiensis 成比例减少，然后随着 2004 年和 2006 年国家蚊帐分配计划的开始，随着蚊帐拥有量的增加，冈比亚 A. gambiae s.s 急剧下降至稀有程度。到 2009 年，A. gambiae s.s.约占比例。 1% 的室内收藏和 99% 的阿拉伯阿拉伯。与2003年的Asembo相比，Seme的冈比亚A. gambiae s.s.幼虫比例更高，幼虫密度更高，并且占据了更多的幼虫栖息地。随着塞梅蚊帐使用量的增加，冈比亚疟原虫幼虫的比例也下降了。这些趋势一直持续到 2009 年。与 Seme（蚊帐使用量低）相比，Asembo（蚊帐使用量高）两个物种的胎次和疟疾感染率均较低，但两个群落的物种内寄主选择并没有变化（A. arabiensis 主要是牛，A. gambiae s.s. 主要是人类）。冈比亚 A. gambiae s.s. 显着下降。随着肯尼亚西部地区家庭拥有蚊帐的数量在 10 年间不断增加，人口数量也随之增加。床网覆盖范围的增加可能对冈比亚 A. gambiae s.l. 的组成产生了质量效应。物种复杂，导致观察到阿拉伯阿拉伯比其密切相关的兄弟物种冈比亚阿拉伯 A. gambiae s.s. 成比例增加。这些观察结果对于评估区域疟疾消除进程非常重要，这需要将持续的病媒控制作为主要干预措施。
High coverage of insecticide-treated bed nets in Asembo and low coverage in Seme, two adjacent communities in western Nyanza Province, Kenya; followed by expanded coverage of bed nets in Seme, as the Kenya national malaria programme rolled out; provided a natural experiment for quantification of changes in relative abundance of two primary malaria vectors in this holoendemic region. Both belong to the Anopheles gambiae sensu lato (s.l.) species complex, namely A. gambiae sensu stricto (s.s.) and Anopheles arabiensis. Historically, the former species was proportionately dominant in indoor resting collections of females. Data of the relative abundance of adult A. gambiae s.s. and A. arabiensis sampled from inside houses were obtained from the literature from 1970 to 2002 for sites west of Kisumu, Kenya, to the region of Asembo ca. 50 km from the city. A sampling transect was established from Asembo (where bed net use was high due to presence of a managed bed net distribution programme) eastward to Seme, where no bed net programme was in place. Adults of A. gambiae s.l. were sampled from inside houses along the transect from 2003 to 2009, as were larvae from nearby aquatic habitats, providing data over a nearly 40 year period of the relative abundance of the two species. Relative proportions of A. gambiae s.s. and A. arabiensis were determined for each stage by identifying species by the polymerase chain reaction method. Household bed net ownership was measured with surveys during mosquito collections. Data of blood host choice, parity rate, and infection rate for Plasmodium falciparum in A. gambiae s.s. and A. arabiensis were obtained for a sample from Asembo and Seme from 2005. Anopheles gambiae s.s. adult females from indoor collections predominated from 1970 to 1998 (ca. 85%). Beginning in 1999, A. gambiae s.s decreased proportionately relative to A. arabiensis, then precipitously declined to rarity coincident with increased bed net ownership as national bed net distribution programmes commenced in 2004 and 2006. By 2009, A. gambiae s.s. comprised proportionately ca. 1% of indoor collections and A. arabiensis 99%. In Seme compared to Asembo in 2003, proportionately more larvae were A. gambiae s.s., larval density was higher, and more larval habitats were occupied. As bed net use rose in Seme, the proportion of A. gambiae larvae declined as well. These trends continued to 2009. Parity and malaria infection rates were lower in both species in Asembo (high bed net use) compared to Seme (low bed net use), but host choice did not vary within species in both communities (predominantly cattle for A. arabiensis, humans for A. gambiae s.s.). A marked decline of the A. gambiae s.s. population occurred as household ownership of bed nets rose in a region of western Kenya over a 10 year period. The increased bed net coverage likely caused a mass effect on the composition of the A. gambiae s.l. species complex, resulting in the observed proportionate increase in A. arabiensis compared to its closely related sibling species, A. gambiae s.s. These observations are important in evaluating the process of regional malaria elimination, which requires sustained vector control as a primary intervention.
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影响因子：
2.1
作者：
BEIER, JC;PERKINS, PV;KOECH, DK
通讯作者：
KOECH, DK
DOI：
10.1080/00034983.1975.11686988
发表时间：
1975-01-01
影响因子：
--
作者：
JOSHI, GP;SERVICE, MW;PRADHAN, GD
通讯作者：
PRADHAN, GD
影响因子：
2.1
作者：
Legros M;Lloyd AL;Huang Y;Gould F
通讯作者：
Gould F
影响因子：
120.7
作者：
Lindblade, KA;Eisele, TP;Slutsker, L
通讯作者：
Slutsker, L
DOI：
10.4269/ajtmh.2003.68.16
发表时间：
2003-04-01
影响因子：
3.3
作者：
Gimnig, JE;Vulule, JM;Hawley, WA
通讯作者：
Hawley, WA