Water Physicochemical Parameters and Microbial Composition Distinguish Anopheles and Culex Mosquito Breeding Sites: Potential as Ecological Markers for Larval Source Surveillance

Abstract

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.

Assessing the effects of native and alien plant ash on mosquito abundance

“…In the current study, we recorded high abundances of Culex mosquitoes compared to Anopheles , and we thus concluded that the environmental conditions i.e., temperature, and the entire water chemistry (Kinga et al, 2022) greatly attracted Culex mosquitoes over Anopheles mosquitoes. However, in the other studies conducted in Sudan (Seufi & Galal, 2010), South Africa (Munhenga et al, 2014), and Tanzania (Emidi et al, 2017), high abundances of Anopheles mosquitoes have been recorded during the same period (November–December), probably because they are not container breeders and possibly prefer cleaner water (Munga et al, 2005) compared to the Culex mosquitoes that are usually found in high abundances in waters with impurities (Medlock & Vaux, 2014).…”

Comparative assessment of the bacterial communities associated with Anopheles darlingi immature stages and their breeding sites in the Brazilian Amazon

“…Mosquito breeding sites are complex environments with several biotic and abiotic features generating suitable conditions that promote the development of vast communities of microbes [ 50 , 51 ]. Mosquito larvae are usually non-selective filter feeders of microorganisms and organic particles suspended in water [ 52 ].…”

Relationships between water quality and mosquito presence and abundance: a systematic review and meta-analysis

“…Water quality-mosquito relationships may be species-dependent, adding to the complexities of predicting MPA broadly (Mercer et al 2005, Burroni et al 2013, Gardner et al 2013, Abai et al 2016, Cepeda-Palacios et al 2017). The impact of water quality on MBD persistence has been acknowledged in recent years (Yee et al 2019, Nagy et al 2021, Neff and Dharmarajan 2021, Fazeli-Dinan et al 2022, Kinga et al 2022); however, the extent of variation in the magnitude and direction of its effects on mosquitoes at the species-, genus-, and family-level is less clear. Therefore, there is a need to investigate water quality determinants for MPA to increase the fidelity of MBD risk assessments.…”