Frequency of Aedes aegypti and Aedes albopictus larvae and pupae in traps,Brazil

Objective To evaluate the monthly frequency of larvae and pupae of Aedes albopictus, Aedes aegypti and other mosquitoe species in tires. and the influence of en vironmental factors on that. Methods The immature stages of mosquitoes were collected monthly from four tires in the municipality of Nova Iguacu. Brazil, from November 1997 to October 199 8. The following variables were measured: rainfall, temperature, water volu me, water pH. The tires were arranged in a pyramid, one at the base (tire 1 ) and 3 others (2,3 e 4) laying over it. Results Were collected 10,310 larvae and 612 pupae. Aedes albopictus was the most c ommon species in both the larval and pupal stages. Aedes aegypti and Aedes albopictus were collected throughout the year but were more frequent during in the rainy season. The number of Aedes aegypti was significantly, correl ated with the temperature, rainfall and water volume of the tires. The corr elation between water pH and number of larvae was not significant. Aedes al bopictus larvae Were in tires left in the shade. Conclusions Aedes albopictus was more abundant in tires than Aedes aegypti. Discarded f ires seem to be an important source of both Aedes species throughout the ye ar. The favored environmental conditions of the tired, such as water volume and exposure to sunlight differ for Aedes albopictus and Aedes aegypti.