Biology subjects

Agossa, F.

Publications and source records attributed to Agossa, F..

3 recordsLinked to original sources

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↗

bioRxiv2021

Modelling spatiotemporal trends in the frequency of genetic mutations conferring insecticide target-site resistance in African malaria vector species

Resistance in malaria vectors to pyrethroids, the most widely used class of insecticides for malaria vector control, threatens the continued efficacy of vector control tools. Target-site resistance is an important genetic resistance mechanism caused by mutations in the voltage-gated sodium channel (Vgsc) gene that encodes the pyrethroid target-site. Understanding the geographic distribution of target-site resistance, and temporal trends across different vector species, can inform strategic deployment of vector control tools. Here we develop a Bayesian statistical spatiotemporal model to interpret species-specific trends in the frequency of the most common resistance mutations, Vgsc-995S and Vgsc-995F, in three major malaria vector species Anopheles gambiae, An. coluzzii, and An. arabiensis. For nine selected countries, we develop annual predictive maps which reveal geographically-structured patterns of spread of each mutation at regional and continental scales. The results show associations, as well as stark differences, in spread dynamics of the two mutations across the three vector species. The coverage of ITNs was an influential predictor of Vgsc allele frequencies in our models. Our mapped Vgsc allele frequencies are a significant partial predictor of phenotypic resistance to the pyrethroid deltamethrin in An. gambiae complex populations, highlighting the importance of molecular surveillance of resistance mechanisms.

genetics↗