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Background: Measure the populations of Ae. aegypti and Ae. albopictus adults according to sex and location inside or outside the residence, estimate Ae. aegypti female density per house and per resident, and test the association with abiotic factors., Methods: Adult mosquitoes were collected monthly with a hand net and portable electric catcher in the peridomiciliary and intradomiciliary premises of residences in an urban area with ongoing dengue transmission in the municipality of São Sebastião, Brazil, from February 2011 to February 2012., Results: Of the 1,320 specimens collected, 1,311 were Ae. aegypti, and nine were Ae. albopictus. A total of 653 male and 658 female of Ae. aegypti were recorded, of which 80% were intradomiciliary. The mean density of Ae. aegypti adult females was 1.60 females/house and 0.42 females/resident. There was an association between the number of females and the number of residents in both intradomiciliary and peridomiciliary premises (r(2) = 0.92; p < 0.001 and r(2) = 0.68; p < 0.001, respectively). There was an association between the number of females and the mean and total rainfall; the correlation was better in peridomiciliary premises (p = 0.00; r(2) = 77%) than intradomiciliary premises in both cases (p = 0.01; r(2) = 48%). Minimum temperature was associated in both environments, exhibiting the same coefficient of determination (p = 0.02; r(2) = 40%). The low frequency of Ae. albopictus (seven females and two males) did not allow for detailed evaluation., Conclusions: Ae. aegypti is well established within the urban area studied, and the frequency of isolation is higher inside the houses. Female density was directly proportional to the number of residents in the houses. Our data show that human population density positively affects the number of Ae. aegypti females within the residence. Meteorological variables also affected mosquito populations. These data indicate a high probability of human-vector contact, increasing the possible transmission and spread of the DEN virus. Entomological indicators of adult females revealed important information complimenting what was obtained with traditional Stegomyia indices. This information should be a part of an interconnected data set for evaluating and controlling the vector.

This study sought to identify people's knowledge on dengue and its vector biology, aimed at promoting a communications channel between technical and lay reasoning in order to foster community involvement in dengue and dengue vector control activities. A survey was conducted in an Aedes aegypti-infested area with dengue transmission in São Sebastião on the northern coast of São Paulo State, Brazil. One hundred interviews were held, with five open questions on topics related to dengue and vector control. Collective Subject Discourse methodology was used in the analysis. People were not able to properly identify the kinds of accumulated water sources that serve as breeding places for mosquitoes and were unaware of the egg phase in vector development. There was inadequate awareness of vector biology and a need for greater government-community integration. Educational activities should incorporate the study results as insight for improving the social efficiency and efficacy of joint actions to fight dengue and control the mosquito vector.

Objective: To describe the occurrence of autochthonous dengue cases according to sex, age, suspected infection site and its relation with climatic variables., Methods: Autochthonous dengue cases reported in São Sebastião, Southern Brazil, from 2001 to 2002 and confirmed in laboratory were studied. Larval density was verified by three indexes: building, recipients and Breteau. The relationship between rainfall, temperature and number of cases was analyzed through Spearman's correlation using time lag., Results: The annual incidence coefficients for 2001 and 2002 were 80.3 and 211.1 per 10,000 inhabitants, respectively. Most dengue cases (n=1,091; 65%) were reported in the district's central area. Females (n=969; 60%) and the age groups 20 to 29 and 30 to 39 years old of both sexes were mostly affected. Significant associations were not observed between climatic variables and the number of dengue cases in the first month; however, this association became evident in the second month throughout the fourth month., Conclusions: The association between the number of dengue cases and abiotic factors identified the time lag in which rain and temperature favored the occurrence of new cases. These aspects, associated to tourist vulnerability in the coastal area, promoted conditions for dengue occurrence. The urbanization without sanitary infrastructure possibly affected mosquito density and dengue incidence. Such factors may have contributed to mosquito dispersion and dissemination of different dengue serotypes.