[ Identification des mécanismes impliqués dans la résistance observée chez Anopheles gambiae sensu lato dans la zone d’Oyem (Nord du Gabon) ]
Volume 40, Issue 4, October 2023, Pages 1413–1422
Pyazzi Obame Ondo Kutomy1, Roland Christophe Zinga Koumba2, Aubin Armel Koumba3, Seynabou Diedhiou Mocote4, Coumba Diouf5, Faye Ousmane6, and Jacques François Mavoungou7
1 Université Cheikh Anta Diop de Dakar (UCAD), BP: 5005, Dakar-Fann, Senegal
2 Institut de Recherche en Ecologie Tropicale (IRET), BP: 13354, Libreville, Gabon
3 Departement de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale, Libreville, Gabon
4 Université Cheikh Anta Diop de Dakar (UCAD), BP: 5005, Dakar-Fann, Senegal
5 Université Cheikh Anta Diop de Dakar (UCAD), BP: 5005, Dakar-Fann, Senegal
6 Faculty of Technical Science, Department of Animal Biology, University Cheikh Anta Diop, Senegal
7 Institut de Recherche en Ecologie Tropicale (IRET), BP: 13354, Libreville, Gabon
Original language: French
Copyright © 2023 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The resistance of malaria vectors to insecticides used in vector control is a major obstacle for national malaria control programs. It is in this context that an entomological study was conducted in urban, peri-urban and rural sites in the Oyem area (Northern Gabon). This study looks at species of the An. gambiae complex and the resistance mechanisms developed by Anopheles to escape to insecticides in Oyem, northern Gabon. To this end, Anopheles larvae were collected in the above-mentioned areas and reared to the adult stage in the field laboratory. Subsequently, the adult anopheles were subjected to sensitivity tests following the World Health Organization protocol. Seven insecticides (DDT 4%, Deltamethrin 0.05%, Permethrin 0.75%, Lambda-cyhalothrin 0.05%, Cyfluthrin 0.15%, Bendiocarb 0.1% and Malathion 5%) were used for these bioassays. The mosquitoes tested (live and dead) were analyzed using PCR to identify the species of the An. gambiae complex. The results obtained showed that the species Anopheles gambiae, the only species identified, has resistance to dichlorodiphenyltrichloroethane (DDT 4%) and Pyrethroids. However, this species is sensitive to Bendiocarb 0.1% and Malathion 5%. These statuses are confirmed by the presence of Kdr mutations (East and West) and the absence of the Ace-1R mutation in this vector.
Author Keywords: Anophèles gambaie, Insecticides, Kdr, Ace-1R, Oyem, Gabon.
Volume 40, Issue 4, October 2023, Pages 1413–1422
Pyazzi Obame Ondo Kutomy1, Roland Christophe Zinga Koumba2, Aubin Armel Koumba3, Seynabou Diedhiou Mocote4, Coumba Diouf5, Faye Ousmane6, and Jacques François Mavoungou7
1 Université Cheikh Anta Diop de Dakar (UCAD), BP: 5005, Dakar-Fann, Senegal
2 Institut de Recherche en Ecologie Tropicale (IRET), BP: 13354, Libreville, Gabon
3 Departement de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale, Libreville, Gabon
4 Université Cheikh Anta Diop de Dakar (UCAD), BP: 5005, Dakar-Fann, Senegal
5 Université Cheikh Anta Diop de Dakar (UCAD), BP: 5005, Dakar-Fann, Senegal
6 Faculty of Technical Science, Department of Animal Biology, University Cheikh Anta Diop, Senegal
7 Institut de Recherche en Ecologie Tropicale (IRET), BP: 13354, Libreville, Gabon
Original language: French
Copyright © 2023 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
The resistance of malaria vectors to insecticides used in vector control is a major obstacle for national malaria control programs. It is in this context that an entomological study was conducted in urban, peri-urban and rural sites in the Oyem area (Northern Gabon). This study looks at species of the An. gambiae complex and the resistance mechanisms developed by Anopheles to escape to insecticides in Oyem, northern Gabon. To this end, Anopheles larvae were collected in the above-mentioned areas and reared to the adult stage in the field laboratory. Subsequently, the adult anopheles were subjected to sensitivity tests following the World Health Organization protocol. Seven insecticides (DDT 4%, Deltamethrin 0.05%, Permethrin 0.75%, Lambda-cyhalothrin 0.05%, Cyfluthrin 0.15%, Bendiocarb 0.1% and Malathion 5%) were used for these bioassays. The mosquitoes tested (live and dead) were analyzed using PCR to identify the species of the An. gambiae complex. The results obtained showed that the species Anopheles gambiae, the only species identified, has resistance to dichlorodiphenyltrichloroethane (DDT 4%) and Pyrethroids. However, this species is sensitive to Bendiocarb 0.1% and Malathion 5%. These statuses are confirmed by the presence of Kdr mutations (East and West) and the absence of the Ace-1R mutation in this vector.
Author Keywords: Anophèles gambaie, Insecticides, Kdr, Ace-1R, Oyem, Gabon.
Abstract: (french)
La résistance des vecteurs du paludisme aux insecticides utilisés dans la lutte antivectorielle est un obstacle majeur pour les programmes nationaux de lutte contre le paludisme. C’est dans ce contexte qu’une étude entomologique a été menée en zone urbaine, péri-urbaine et rurale dans la zone d’Oyem (Nord du Gabon). Cette recherche s’intéresse aux mécanismes de résistance développés par les espèces du complexe An. gambaie pour échapper aux insecticides à Oyem au Nord du Gabon. A cet effet, des larves d’anophèles ont été collectées dans les zones précitées, puis élevées jusqu’au stade adultes au laboratoire de terrain. Par la suite, les anophèles adultes ont été soumis aux tests de sensibilité suivant le protocole de l’Organisation Mondiale de la Santé. Sept insecticides (DDT 4%, Deltaméthrine 0,05%, Perméthrine 0,75%, Lambda-cyhalothrine 0,05%, Cyfluthrine 0,15%, Bendiocarbe 0,1% et Malathion 5%) ont été utilisés pour ces bioéssais. Les moustiques testés (vivants et morts) ont été analysés via la PCR afin d’identifier les espèces du complexe An. gambiae. Les résultats obtenus ont montré que l’espèce Anopheles gambiae, seule espèce identifiée, présente une résistance au dichlorodiphényltrichloroéthane (DDT 4%) et aux Pyréthrinoïdes. Cependant, cette espèce est sensible au Bendiocarbe 0,1% et au Malathion 5%. Ces statuts sont confirmés par la présence des mutations Kdr (East et West) et l’absence de la mutation Ace-1R chez ce vecteur.
Author Keywords: Anophèles gambaie, Insecticides, Kdr, Ace-1R, Oyem, Gabon.
How to Cite this Article
Pyazzi Obame Ondo Kutomy, Roland Christophe Zinga Koumba, Aubin Armel Koumba, Seynabou Diedhiou Mocote, Coumba Diouf, Faye Ousmane, and Jacques François Mavoungou, “Identification of the mechanisms involved in the resistance observed in Anopheles gambiae sensu lato in the Oyem area (Northern Gabon),” International Journal of Innovation and Applied Studies, vol. 40, no. 4, pp. 1413–1422, October 2023.
