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INTRODUCTION: The occurrence of American cutaneous leishmaniasis in the region of the Paraiba valley and the Northern shore of the State of S. Paulo, Brazil, is studied by remote sensing satellite imagery and maps of the region. METHOD: The places where infections might have occurred were plotted on a false color composition made up of Landsat TM-3, 4 and 5 band images, the relevant vegetation (shrubs and trees) has been identified and correlations were sought for those areas seen as areas of risk for the disease and the environmental characteristics and their changes. The maps made it possible to add to the composite image the creeks and the contours of the tops of the large number of hills found in that region. RESULTS: An area is characterized which may prove to be a macro-habitat for vectors, reservoirs and etiological agents. The search for changes in the landscape and the evaluation of meteorological data has not yielded any possible additional risk factor. CONCLUSIONS: There is full correlation among the areas considered to present risk of infection and the presence of creeks and relevant vegetation (shrubs and trees).

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The areas in which american cutaneous leishmaniasis was reported in 1993 and 1994 for the region around the town of Lagoinha, S. Paulo, Brazil (Lat 23 degrees 05' S; Long 45 degrees 11w) were plotted on a TM-LANDSAT image. The false color composition of bands 3, 4 and 5 made it possible to identify the relevant vegetation (shrubs and trees) within the boundaries of those areas and in their proximity, where they were found at a distance of not more than about 250 meters from the perimeter of each area. The use of means capable of presenting a larger view of a geographical area made the advantages of remote satellite sensing as a tool for the study of this endemic disease clear.

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Aedes albopictus were reared in different containers: a tree hole, a bamboo stump and an auto tire. The total times from egg hatching to adult emergence were of 19.6, 27.3 and 37.5 days, respectively, according to the container. The first, second and third-instar larvae presented growth periods with highly similar durations. The fourth-instar larvae was longer than the others stages. The pupation time was longer than the fourth-instar larvae growth period. The temperature of the breeding sites studied, which was of 18 degrees C to 22 degrees C on average, was also taken into consideration. The mortality of the immature stages was analysed and compared as between the experimental groups; it was lower in the natural containers than in the discarded tire. The average wing length of adult females emerging from tree hole was significantly larger (p < 0.05) than that of those emerging from the tire.

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A comparative study of the efficiency of ovitraps and larval-traps was undertaken with a view to improving the entomological survey of vectors of Dengue and Yellow Fever-Aedes aegypti and Aedes albopictus-in S. Paulo State, Brazil. The region studied is infected only by Aedes albopictus, a species that keeps to wild habitats but colonizes artificial breeding grounds as well. The first part of the study was located in a periurban area of Tremembé county were 3 hollon trees, 23 ovitraps and 5 larval-traps were compared. The second part of these experiments took place in Lavrinhas county (Pinheiros district), where 20 ovitraps and 5 larval-traps were tested. The results showed that the ovitrap was more efficient than larval-traps and were positive even in the presence of natural breeding grounds. It was also observed un the evaluation of the results of "thermonebulization (fog)" that the ovitraps showed strong reduction in the average number of eggs, but this was not observed in the Breteau Index.

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Larval, pupae and egg water extracts were tested for their influence on the oviposition behavior of Aedes (s) albopictus females. Significant (alpha = 0.05) attraction was exercised by larval and pupal extracts containing 1 larva/3 ml and 1 pupa/3 ml. Eggs water extract containing 1 egg/3 ml did not influence the oviposition.

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The objective of this study was the determination of extent of the spatial distribution of Aedes albopictus in the Paraíba River Valley, State S. Paulo, Brazil. Thus, collections of larvae and pupae mosquitoes were carried out at six sites distributed along a transection with a 10-km extension. The target was the tree-holes but artificial containers were also used in this investigation. Aedes terrens and Ae. albopictus were the only species of genus Aedes present in the tree-holes mentioned. The segregation of seven species of the tree-hole community was undertaken in the light of macrohabitat and microhabitat features. Thus, the distribution of Ae. albopictus was found to cover the rural, rural-urban and urban zones, but the rural-urban held the preference. Ae. albopictus never present in the residual and primary forest. The favorable factor to infestation with Ae. albopictus in the Paraíba Valley seems to have been the large number of natural niches made vacant by human influence. The rain has been important in the production of larvae and pupae, but the rainfall period does not coincide with the maximum production on them. The tree-holes whose volume exceeded 600 ml were the most productive breeding places. The abundance of these two stages occurs in the summer and autumn. However, the highest peak was observed in the months of March and April. These seasonal variations were found to be common in both the bamboo trap and the artificial container. The temperature data suggest a limit of from 17 to 23 degrees C for the best development of larvae. In the light of this, the strain of Ae. albopictus studied seems to have originated in tropical Asia. Just as happened with Ae. aegypti it may become an important epidemiological vector for the dengue fever and provide links for yellow fever transmission in Brazil.

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This study reports the finding of Biomphalaria tenagophila naturally aestived in two municipalities of the State of S. Paulo (Brazil): Ubatuba and Conchas. This ethological characteristic was discovered in 15 specimens collected in Ubatuba, and in 6 specimens collected in Conchas. The snails aestived showed vitality after being placed in water.

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