[Comparison of 2 populations of Aedes aegypti mosquitoes from Santiago de Cuba with different rest conduct].

Two populations of Aedes aegypti that were collected in Santiago de Cuba during the epidemics of 1971 were separated for having different rest habits, some of them rested naturally on the walls up to 1 m high (Santiago de Cuba strain) and the others were found resting in the roofs of the houses (Santiago de Cuba Techo strain). These strains did not show significant differences as regards their morphological characteristics. The mosquitoes corresponding to Santiago de Cuba Techo strain presented the same patches that those of Santiago de Cuba. The resistance to organophosphate insecticides is very similar in both populations; however, the Santiago de Cuba Techo strain shows a higher resistance to pyrethroid deltamethrin than the Santiago de Cuba strain. From the biochemical point of view and by using the DEF synergist, it was proved that esterases are associated with the high resistance to clorpirifos in both strains. It was not so with the MFO, which was demonstrated by means of the piperomyl butoxide sinergist. Nevertheless, the GST enzyme seems to be responsible for the high resistance to deltamethrin detected in the Santiago de Cuba Techo strain due to the elevated frequency value of that gene in this strain. The random amplified polymorphic DNA technique was used to observe the genetic variability between the 2 populations. The results revealed that there was genetic polymorphism between the populations under study, which could have an impact on the ecology and epidemiology of the vector.