[Resistance to insecticides in larvae and adults of Aedes aegypti, Havana City: prevalence of A4 esterasa associated with resistance to temephos].

2 strains of Aedes aegypti from 2 people's councils with high indexes of infestation of this vector were studied due to the need of carrying out an effective control of larvae and adults in the municipality of Guanabacoa. The levels of susceptibility and/or resistance to organophosphate insecticides, pyrethroids and a carbamate were determined. The results of the bioassays in larvae showed a complete susceptibility to organophosphate insecticides, malathion, clorpirifos, methyl-pyrimifos and propoxur carbamate in both people's councils. However, it was observed a high resistance to temephos and fenthion. No resistance to fenitrothion was found in one of the people's councils. At the adult stage and at the dose recommended by the World Health Organizaton or by the product manufacturers, it was observed resistance to malathion, fenitrothion and propoxur; nevertheless, better results were obtained with the pyrethroids, with mortality percentages over 90%. According to the results obtained, by using the SSS tributyl phosphotritiade sinergist (DEF) and piperonyl butoxide, it was demonstrated that the multiple function esterases and oxidases played an important role in the resistance to temephos and fenthion. It was proved that he amplified activity of these enzymes was at an elevated frequency in both people's councils, the same as the glutathione transferase (GST) in one of the 2 people's councils. It was observed that in both people's councils prevailed the amplified activity of A4 esterases by polyacrylamide gel electrophoresis.