Insecticide susceptibility status of Anopheles gambiae s.l. (Diptera: Culicidae) in the Republic of Cameroon.
A large-scale survey of Anopheles gambiae Giles, 1902 susceptibility to DDT, dieldrin, permethrin, and deltamethrin was conducted in the Republic of Cameroon. 15 field populations from various geographical areas were tested using World Health Organization test kits for adult mosquitoes. The laboratory Kisumu susceptible reference strain was tested as a control. Results showed that dieldrin and DDT resistance was still present in some populations, and indicated permethrin or deltamethrin resistance. Within the Anopheles gambiae complex, resistant individuals belonged to An. gambiae s.s. and An. arabiensis species. Both M and S molecular forms of An. gambiae s.s. were found resistant. In most of resistant populations, the knockdown times were 2-5-folds increased. However, none of the surviving mosquitoes was positive to the kdr "Leu-Phe" mutation using polymerase chain reaction (PCR) diagnostic test. These results likely suggested involvement of other resistance mechanism(s), such as enzyme detoxification or kdr "Leu-Ser" mutation. Researches on An. gambiae s.l. resistance should be promoted in Cameroon, to improve malaria vector control programs and to implement resistance management strategies.
Etang
Josiane
J
Institut de Recherches Médicales et d'étude des Plantes Médicinales/Centre de Recherches Médicales/Ministère de la Recherche Scientifique et Technique du Cameroun, Yaounde, Cameroon. josyet@yahoo.fr
Manga
Lucien
L
Chandre
Fabrice
F
Guillet
Pierre
P
Fondjo
Etienne
E
Mimpfoundi
Remy
R
Toto
Jean-Claude
JC
Fontenille
Didier
D
D000818:Animals; D000852:Anopheles / Q000235:genetics / Q000502:physiology; D002163:Cameroon; D002980:Climate; D003634:DDT / Q000633:toxicity; D004026:Dieldrin / Q000633:toxicity; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005787:Gene Frequency; D005843:Geography; D007306:Insecticides / Q000633:toxicity*; D009570:Nitriles; D026023:Permethrin / Q000633:toxicity; D011722:Pyrethrins / Q000633:toxicity
D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin; D026023:Permethrin; D003634:DDT; D004026:Dieldrin