title: Insecticide resistance in Brazilian Triatoma infestans and Venezuelan Rhodnius prolixus.
abstract: Resistance levels to insecticides used in control of Chagas Disease vectors were assessed in two species of bugs (Hemiptera: Reduviidae): Triatoma infestans (Klug) from Brazil and Rhodnius prolixus Stål from Venezuela. The resistance ratios, compared to susceptible laboratory strains, were determined by topical application bioassays. The T. infestans PA strain exhibited resistance ratios of 7x to deltamethrin, 3.6x to beta-cyfluthrin and 3.3x to cypermethrin, but was susceptible to beta-cypermethrin and lambda-cyhalothrin. Rhodnius prolixus CA strain showed resistance to all the pyrethroids evaluated, the resistance ratios ranging between 4.5x to lambda-cyhalothrin and 12.4x to cypermethrin. Deltamethrin resistance in both strains was decreased by piperonyl butoxide, suggesting oxidative metabolism as cause of resistance.
authors.affiliation: Centro de Investigaciones de Plagas e Insecticidas, Buenos Aires, Argentina. cipein@citefa.gov.ar
authors.forename: C V
authors.initials: CV
authors.lastname: Vassena
authors.forename: M I
authors.initials: MI
authors.lastname: Picollo
authors.forename: E N
authors.initials: EN
authors.lastname: Zerba
mesh_terms: D000287:Administration, Topical; D000818:Animals; D001938:Brazil; D004026:Dieldrin / Q000008:administration & dosage / Q000494:pharmacology; D004357:Drug Synergism; D007305:Insecticide Resistance; D007306:Insecticides / Q000008:administration & dosage / Q000494:pharmacology*; D010882:Piperonyl Butoxide / Q000008:administration & dosage / Q000494:pharmacology; D010944:Plants; D011722:Pyrethrins; D012239:Rhodnius; D014224:Triatoma; D014349:Trypanosoma cruzi; D014687:Venezuela
chemical_list: D007306:Insecticides; D011722:Pyrethrins; D004026:Dieldrin; D010882:Piperonyl Butoxide