Journal Article

Bionomics of Anopheles gambiae complex (Diptera: Culicidae) and malaria transmission pattern in a pre-elimination area in South–Western Senegal

Ciss, Oumar, Coulibaly, Youssouph, Faye, Ousmane, Diop, Abdoulaye, Konaté, Abdoulaye, Konaté, Lassana, Diédhiou, Seynabou Mocote, Thiaw, Omar, Niang, El Hadji Amadou, Faye, Mouhamadou Bassir, Ndoye, Ndèye Aita, Diop, Moussa, Diallo, Moussa, Tall, Mame Fatou, Sangaré, Modibo, Samb, Badara, Niang, Abdoulaye, Tine, Roger Clément Kouly, Coulibaly, Yaya Ibrahim, Dia, Abdoulaye Kane

2025

Overview

BackgroundMalaria remains a public health problem in many African countries. In Senegal, the Southern region had the highest malaria incidence and malaria-related deaths. The relationship between vector density and malaria transmission remains poorly understood in some specific areas. The aim of this study was to characterize the current entomological and transmission parameters with special emphasis on the Anopheles gambiae complex in the malaria pre-elimination area of Mlomp south-western Senegal.MethodsThe study was conducted from July 2020 to February 2021 in Djicomol and Cadjinolle in the commune of Mlomp region of Ziguinchor, Senegal. Sampling was carried out using Human Landing Catches (HLC) and Pyrethrum Spray Catches (PSC). Ovaries were dissected to determine female parity rate. Infection status, blood meal sources and species molecular identification were determined using Enzyme-Linked Immunosorbent Assay (ELISA) and Polymerase Chain Reaction (PCR) techniques respectively.ResultsA total of 6956 mosquitoes of the An. gambiae complex were collected, of which 6739 were by HLC (96.88%) and 217 by PSC (3.12%). The mean human biting rate was 36.98 bites/person/night (b/p/n) indoors and 43.25 b/p/n outdoors. Female biting activity was more frequent during the second half of the night. Mean parity rates were 24.83% indoors and 18.94% outdoors. The human blood index was estimated at 76.09%. Overall, An. gambiae sensu stricto (s.s.) was the most common species (75.08%). No female An. gambiae was found to be infected with Plasmodium falciparum in the sub-sample tested, thus no malaria transmission was recorded in Mlomp during the study period.ConclusionsThe results alert malaria control programme to develop additional strategies for controlling these vectors, which show exophagic behaviours to effectively combat malaria.

• Publisher: Springer Nature B.V
• Subject: Anopheles gambiae / Bionomics / Biting / Blood / Culicidae / Disease transmission / ELISA / Enzyme-linked immunosorbent assay / Females / Human diseases / Infections / Malaria / Mosquitoes / Nucleotide sequence / Outdoors / Ovaries / Polymerase chain reaction / Public health / Vector-borne diseases / Vectors / Vectors (Biology)