Biology subjects

Zanga, J.

Publications and source records attributed to Zanga, J..

3 recordsLinked to original sources

bioRxiv2024

Cryptic population structure and insecticide resistance in Anopheles gambiae from the southern Democratic Republic of Congo

The Democratic Republic of Congo (DRC) suffers from one of the highest malaria burdens worldwide, but information on its Anopheles vector populations is relatively limited. Preventative malaria control in DRC is reliant on pyrethroid-treated nets, raising concerns over the potential impacts of insecticide resistance. We sampled Anopheles gambiae from three geographically distinct populations (Kimpese, Kapolowe and Mikalayi) in southern DRC, collecting from three sub-sites per population and characterising mosquito collections from each for resistance to pyrethroids using WHO tube bioassays. Resistance to each of three different pyrethroids was generally high in An. gambiae with <92% mortality in all tests, but varied between collections, with mosquitoes from Kimpese being the most resistant. Whole genome sequencing of 165 An. gambiae revealed evidence for genetic differentiation between Kimpese and Kapolowe / Mikalayi, but not between the latter two sample sites despite separation of approximately 800km. Surprisingly, there was evidence of population structure at a small spatial scale between collection subsites in Kimpese, despite separation of just tens of kilometres. Intra-population (H12) and inter-population (FST) genome scans identified multiple peaks corresponding to genes associated with insecticide resistance such as the voltage gated sodium channel (Vgsc) target site on chromosome 2L, a Cyp6 cytochrome P450 cluster on chromosome arm 2R, and the Cyp9k1 P450 gene on chromosome X. In addition, in the Kimpese subsites, the P450 redox partner gene Cpr showed evidence for contemporary selection (H12) and population differentiation (FST) meriting further exploration as a potential resistance associated marker.

evolutionary biology↗

bioRxiv2023

Species Composition and Distribution of Anopheles gambiae Complex Circulating in Kinshasa

Understanding the distribution of Anopheles species in a region is an important task in the planning and implementation of malaria control programmes. This study was proposed to evaluate the composition and distribution of cryptic species of the main malaria vector, Anopheles gambiae complex, circulating in different districts of Kinshasa. To study the distribution of members of the An. gambiae complex, Anopheles were sampled by CDC light trap and larva collection across the four districts of Kinshasa city between July 2021 and June 2022. After morphological identification, an equal proportion of Anopheles gambiae s.l. sampled per site were subjected to polymerase chain reaction (PCR) for identification of cryptic An. gambiae complex species. The Anopheles gambiae complex was widely identified in all sites across the city of Kinshasa, with a significant difference in mean density, captured by CDC light, inside and outside households in Kinshasa (p=0.002). Two species of this complex circulate in Kinshasa: Anopheles gambiae (82.1%) and Anopheles coluzzii (17.9%). In all study sites, Anopheles gambiae was the most prevalent species. Anopheles coluzzii was very prevalent in Tshangu district. No hybrids (Anopheles coluzzii/Anopheles gambiae) were identified. Two cryptic species of the Anopheles gambiae complex circulate in Kinshasa. Anopheles gambiae s.s., present in all districts and Anopheles coluzzii, with a limited distribution. Studies on the ecology of the larval sites are essential to better understand the factors influencing the distribution of members of the An. gambiae complex in this megalopolis.

zoology↗

bioRxiv2023

Data from Entomological Collections of Aedes (Diptera: Culicidae) in a post-epidemic area of Chikungunya, City of Kinshasa, Democratic Republic of Congo

Arbovirus epidemics (e.g. Chikungunya, dengue, West Nile, Yellow Fever, and Zika), are a growing threat in Africa in areas where Aedes (Ae.) aegypti and A. albopictus are present. The lack of complete sampling of these two vectors limits our ability to understand their propagation dynamics in areas at risk from arboviruses. Here, we describe for the first time the geographical distribution of two arbovirus vectors (Ae. aegypti and Ae. albopictus) in a chikungunya post-epidemic zone in the provincial city of Kinshasa, Democratic Republic of Congo between 2020 and 2022. In total 6,943 observations were reported using larval capture and human capture on landing methods. These data are published in the public domain as a Darwin Core archive in the Global Biodiversity Information Facility. The results of this study potentially provide important information for further basic and advanced studies on the ecology and phenology of these vectors, as well as on vector dynamics after an epidemic period. Subject AreasEcology, Biodiversity, Taxonomy Data description

zoology↗