Indoor use of plastic sheeting impregnated with carbamate combined with long-lasting insecticidal mosquito nets for the control of pyrethroid-resistant malaria vectors

Abstract

The combined efficacy of a long-lasting insecticidal net (LLIN) and a carbamate-treated plastic sheeting (CTPS) or indoor residual spraying (IRS) for control of insecticide-resistant mosquitoes was evaluated in experimental huts in Burkina Faso. Anopheles gambiae from the area is resistant to pyrethroids and to a lesser extent, carbamates. Relatively low mortality rates were observed with the LLIN (44%), IRS (42%), and CTPS (52%), whereas both combinations killed significantly more mosquitoes (~70% for LLIN + CTPS and LLIN + IRS). Blood feeding by An. gambiae was uninhibited by IRS and CTPS compared with LLIN (43%), LLIN + CTPS (58%), and LLIN + IRS (56%). No evidence for selection of the kdr and ace-1(R) alleles was observed with the combinations, whereas a survival advantage of mosquitoes bearing the ace-1(R) mutation was observed with IRS and CTPS. The results suggest that the combination of the two interventions constitutes a potential tool for vector-resistance management.

Figures

Figure 1.

Exophily (95% confidence interval) of An. gambiae exposed to LLIN alone and in combination with IRS and CTPS in experimental huts (Vallée du Kou, Burkina Faso). Treatments carrying the same letter are not significantly different (P > 0.05).

Figure 2.

Blood-feeding rate (95% confidence interval) of An. gambiae exposed to LLIN alone and in combination with IRS and CTPS in experimental huts (Vallée du Kou, Burkina Faso). Treatments carrying the same letter are not significantly different (P > 0.05).

Figure 3.

Mortality rate (95% confidence interval) of An. gambiae exposed to LLIN alone and in combination with IRS and CTPS in experimental huts (Vallée du Kou, Burkina Faso). Treatments carrying the same letter are not significantly different (P > 0.05).