Efficacy of mosquito nets treated with a pyrethroid-organophosphorous mixture against Kdr- and Kdr+ malaria vectors (Anopheles gambiae).
In order to prevent the resistance of Anopheles gambiae s.l. to pyrethroids from spreading too quickly and to lengthen the effectiveness of insecticide impregnated mosquito nets, it has recently been suggested to use mixtures of insecticides that have different modes of action. This study presents the results obtained with tulle mosquito nets treated with bifenthrin (a pyrethroid) and chlorpyrifos-methyl (an organophosphorous) both separately and in mixture on two strains of An. gambiae, one sensitive to all insecticides, and the other resistant to pyrethroids. The values of KDt50 and KDt95 and the mortality induced with the mixture of bifenthrin (25 mg/m2) and chlorpyrifos-methyl (4.5 mg/m2) show a significant synergistic effect on the strain of An. gambiae susceptible to insecticides. However, the tested combination does not induce any synergistic effect on the VKPR strain selected with permethrin, but only enhances the effectiveness of the two insecticides taken separately.
Darriet
F
F
LIN/IRD, 911 Avenue Agropolis, BP 64501, 34394 Montpellier, France. darriet@mpl.ird.fr
Corbel
V
V
Hougard
J M
JM
D000818:Animals; D000852:Anopheles / Q000187:drug effects*; D001512:Bedding and Linens; D004390:Chlorpyrifos / Q000031:analogs & derivatives* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D007303:Insect Vectors / Q000187:drug effects*; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology; D008288:Malaria / Q000517:prevention & control; D009032:Mosquito Control / Q000379:methods*; D009943:Organophosphorus Compounds / Q000494:pharmacology*; D011722:Pyrethrins / Q000494:pharmacology*; D016896:Treatment Outcome
D007306:Insecticides; D009943:Organophosphorus Compounds; D011722:Pyrethrins; C099952:bifenthrin; D004390:Chlorpyrifos; C007031:chlorpyrifos-methyl