title: [Susceptibility of natural populations of dengue vector to insecticides in Colombia].
abstract: BACKGROUND
  Physiological resistance of natural population of Aedes aegypti to insecticides contribute to the decreased efficacy of chemical control as a main control strategy during dengue outbreaks.
  
  
  OBJECTIVE
  The susceptibility status of Ae. aegypti was assessed for the carbamate propoxur, the adulticide malathion and the larvicide temephos on 13 natural populations of Ae. aegypti immature forms were taken from 8 Colombian localities. These included the following: Bucaramanga (1), Sabana de Torres (2), Girardot (2), La Mesa (2), Villavicencio (2), Puerto López (2), San José del Guaviare (1) and Florencia (1).
  
  
  METHODS
  Susceptibility tests mainly consisted of the standardized bioassay outlined by WHO (1981) and CDC bottles (1998). Colorimetric tests were undertaken to determine enzyme levels possibly responsible for the reduction of susceptibility to organophosphate and carbamate insecticides.
  
  
  RESULTS
  All specimens demonstrated susceptibility to malathion and propoxur insecticides. Four of the 13 populations revealed susceptibility to the temephos larvicide. Seven of 11 populations showed a limited increase in values for nonspecific esterase enzymes. The Bucaramanga population was the only one which showed an increase in the cytochrome P450 monooxygenases enzymes. Neither population was found with modified acetilcolinesterase.
  
  
  CONCLUSIONS
  The widespread susceptibility to organophosphates used as adulticides indicated that malathion, the most used insecticide in Colombia, remains effective in interrupting the transmission of dengue. Physiological resistance to insecticides occurring in communities of a single township proved to be a localized phenomenon.
authors.affiliation: Laboratorio de Entomología, Subdirección Red Nacional de Laboratorios, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: Liliana
authors.initials: L
authors.lastname: Santacoloma
authors.forename: Bernardo
authors.initials: B
authors.lastname: Chaves
authors.forename: Helena Luisa
authors.initials: HL
authors.lastname: Brochero
mesh_terms: D000110:Acetylcholinesterase / Q000032:analysis; D000330:Aedes / Q000201:enzymology / Q000254:growth & development; D000818:Animals; D003105:Colombia; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis; D003716:Dengue Virus; D018432:Drug Resistance, Multiple; D004950:Esterases / Q000032:analysis; D005260:Female; D019476:Insect Proteins / Q000032:analysis; D007303:Insect Vectors; D007305:Insecticide Resistance; D007306:Insecticides; D007814:Larva; D008294:Malathion; D008297:Male; D009032:Mosquito Control; D001074:Propoxur; D000002:Temefos; D014504:Urban Health
chemical_list: D019476:Insect Proteins; D007306:Insecticides; D003577:Cytochrome P-450 Enzyme System; D001074:Propoxur; D004950:Esterases; D000110:Acetylcholinesterase; D000002:Temefos; D008294:Malathion