PDF(Pubmed)
Abstract：
Landscape heterogeneity creates diverse habitat and resources for mosquito vectors of disease. A consequence may be varied distribution and abundance of vector species over space and time dependent on niche requirements.We tested the hypothesis that landscape heterogeneity driven by urbanization influences the distribution and relative abundance of Culex pipiens, Cx. restuans, and Cx. quinquefasciatus, three vectors of West Nile virus (WNv) in the eastern North American landscape. We collected 9,803 cryptic Culex from urban, suburban, and rural sites in metropolitan Washington, District of Columbia, during the months of June-October, 2019-2021. In 2021, we also collected mosquitoes in April and May to measure early-season abundance and distribution. Molecular techniques were used to identify a subset of collected Culex to species (n = 2,461). Ecological correlates of the spatiotemporal distribution of these cryptic Culex were examined using constrained and unconstrained ordination.Seasonality was not associated with Culex community composition in June-October over three years but introducing April and May data revealed seasonal shifts in community composition in the final year of our study. Culex pipiens were dominant across site types, while Cx. quinquefasciatus were associated with urban environments, and Cx. restuans were associated with rural and suburban sites. All three species rarely coexisted.Our work demonstrates that human-mediated land-use changes influence the distribution and relative abundance of Culex vectors of WNv, even on fine geospatial scales. Site classification, percent impervious surface, distance to city center, and longitude predicted Culex community composition. We documented active Culex months before vector surveillance typically commences in this region, with Culex restuans being most abundant during April and May. Active suppression of Cx. restuans in April and May could reduce early enzootic transmission, delay the seasonal spread of WNv, and thereby reduce overall WNv burden. By June, the highest risk of epizootic spillover of WNv to human hosts may be in suburban areas with high human population density and mixed Culex assemblages that can transmit WNv between birds and humans. Focusing management efforts there may further reduce human disease burden.
摘要：
景观异质性为疾病的蚊子媒介创造了不同的栖息地和资源。结果可能是媒介物种在空间和时间上的分布和丰度取决于生态位要求。我们检验了城市化驱动的景观异质性影响淡色库蚊的分布和相对丰度的假设，Cx.restuans,Cx.Quinquefasciatus,北美东部景观中的西尼罗河病毒（WNv）的三个媒介。我们从城市收集了9,803个神秘的库蚊，郊区,郊区和华盛顿大都市的农村地区，哥伦比亚特区,在6月至10月期间，2019-2021年。在2021年，我们还在4月和5月收集了蚊子，以测量早期季节的丰度和分布。分子技术用于鉴定收集到的库蚊物种的子集（n=2,461）。使用受约束和无约束的排序检查了这些隐匿库蚊时空分布的生态相关性。在过去的三年中，季节性与6月至10月的库蚊群落组成无关，但引入4月和5月的数据表明，在我们研究的最后一年，群落组成发生了季节性变化。淡色库蚊在不同部位类型中占主导地位，而CX。quinquefasciatus与城市环境有关，Cx.restuans与农村和郊区有关。这三个物种很少共存。我们的工作表明，人为介导的土地利用变化会影响WNv的库蚊矢量的分布和相对丰度，甚至在精细的地理空间尺度上。场地分类,不透水表面百分比，距离市中心，和经度预测库蚊群落组成。我们在该地区通常开始进行媒介监测之前的几个月记录了活跃的库蚊，库蚊在4月和5月最丰富。主动抑制Cx。4月和5月的研究可以减少早期的植物性传染病，延迟WNv的季节性传播，从而降低WNv的总体负担。到六月,WNv向人类宿主的流行病溢出的最高风险可能是在人口密度高的郊区以及可以在鸟类和人类之间传播WNv的混合库蚊组合。集中管理努力可以进一步减轻人类疾病负担。
