African Regional Postgraduate Program in Insect Science, University of Ghana, Legon, Ghana.
West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, Legon, Ghana.
J Med Entomol. 2022 Sep 14;59(5):1817-1826. doi: 10.1093/jme/tjac115.
The presence of mosquitoes in an area is dependent on the availability of suitable breeding sites that are influenced by several environmental factors. Identification of breeding habitats for vector surveillance and larval source management is key to disease control programs. We investigated water quality parameters and microbial composition in selected mosquito breeding sites in urban Accra, Ghana and associated these with abundance of Anopheles (Diptera: Culicidae) and Culex (Diptera: Culicidae) larvae. Physicochemical parameters and microbial composition explained up to 72% variance among the breeding sites and separated Anopheles and Culex habitats (P < 0.05). Anopheles and Culex abundances were commonly influenced by water temperature, pH, nitrate, and total hardness with contrasting impacts on the two mosquito species. In addition, total dissolved solids, biochemical oxygen demand, and alkalinity uniquely influenced Anopheles abundance, while total suspended solids, phosphate, sulphate, ammonium, and salinity were significant determinants for Culex. The correlation of these multiple parameters with the occurrence of each mosquito species was high (R2 = 0.99, P < 0.0001). Bacterial content assessment of the breeding ponds revealed that the most abundant bacterial phyla were Patescibacteria, Cyanobacteria, and Proteobacteria, constituting >70% of the total bacterial richness. The oligotrophic Patescibacteria was strongly associated with Anopheles suggestive of the mosquito's adaptation to environments with less nutrients, while predominance of Cyanobacteria, indicative of rich nutritional source was associated with Culex larval ponds. We propose further evaluation of these significant abiotic and biotic parameters in field identification of larval sources and how knowledge of these can be harnessed effectively to reduce conducive breeding sites for mosquitoes.
蚊子在一个地区的存在取决于是否存在合适的繁殖场所，而这些繁殖场所受到多种环境因素的影响。识别蚊子的繁殖栖息地对于疾病防控计划的媒介监测和幼虫源管理至关重要。我们调查了加纳阿克拉市区选定蚊子繁殖地的水质参数和微生物组成，并将这些与疟蚊（双翅目：蚊科）和库蚊（双翅目：蚊科）幼虫的丰度相关联。理化参数和微生物组成解释了繁殖地之间高达 72%的变异，并将疟蚊和库蚊的栖息地分开（P < 0.05）。水温和 pH 值、硝酸盐和总硬度对疟蚊和库蚊的丰度都有共同的影响，但影响方式相反。此外，总溶解固体、生化需氧量和碱度对疟蚊丰度有独特的影响，而总悬浮物、磷酸盐、硫酸盐、铵盐和盐度是库蚊的重要决定因素。这些多个参数与每种蚊子发生的相关性很高（R2 = 0.99，P < 0.0001）。对繁殖池塘的细菌含量评估表明，最丰富的细菌门是 Patescibacteria、蓝藻和变形菌门，占总细菌丰富度的>70%。贫营养的 Patescibacteria 与疟蚊密切相关，表明蚊子适应了营养较少的环境，而富含营养的蓝藻的优势与库蚊幼虫池塘有关。我们建议进一步评估这些重要的非生物和生物参数，以在现场识别幼虫源时使用，并探讨如何有效利用这些知识来减少蚊子的滋生地。
