Marylene de Brito

Microhabitats de Aedes albopictus (Skuse) na região do Vale do Paraíba, Estado de São Paulo, Brasil

The objective of this study was the determination of extent of the spatial distribution of Aedes albopictus in the Paraiba 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 Paraiba 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.

Reservatórios domiciliares de água e controle do Aedes aegypti

Water reservoirs for domestic use are important sites for the development of Aedes aegypti. In poor areas, these reservoirs are often located outdoors upon flat rooftops. In modern architecture buildings, however, the same is seen even in high-class condominiums. Special attention should be given to these modern architectural constructions during entomological surveillance.

Significado epidemiológico dos criadouros de Aedes albopictus em bromélias

A breeding place of immature stages of Aedes albopictus in bromeliads is described. The epidemiological role of bromeliaceae as natural or artificial containers, is discussed. The ability of the mosquito to expand its habitat calls for attention especially as regards its adaptability as an invading species.

Estudo comparativo de eficácia de larvitrampas e ovitrampas para vigilância de vetores de dengue e febre amarela

Com a finalidade de aprimorar a vigilância entomologica dos vetores de Dengue e Febre Amarela - Aedes aegypti e Aedes albopictus - no Estado de Sao Paulo, Brasil, realizou-se estudo comparativo de eficacia de larvitrampas (armadilhas de larvas), e ovitrampas (armadilhas de ovos). A regiao estudada e infestada somente pelo Aedes albopictus, especie que conserva habitos silvestres, mas tambem coloniza criadouros artificiais. A primeira parte do estudo foi realizada em area periurbana de Tremembe-SP, onde foram comparados tres ocos de arvore, 23 ovitrampas e 5 larvitrampas. A segunda parte dos experimentos desenvolveu-se no Municipio de Lavrinhas-SP, no distrito de Pinheiros, onde 20 ovitrampas foram instaladas (uma por quadra) e 5 larvitrampas foram localizadas em pontos estrategicos (comercios, depositos e postos). Os resultados obtidos mostraram que a ovitrampa, alem da capacidade de positivar-se mesmo em presenca de criadouros naturais, possui eficiencia superior a larvitrampa. Constatou-se que para avaliacao de efeitos da termonebulizacao as ovitrampas apresentaram uma significativa reducao na media de ovos, o que nao se verificou em relacao ao Indice de Breteau.

Immature forms of anophelines in artificial containers

Relata-se o encontro de formas imaturas de Anopheles bellator e de An. argyritarsis em recipientes artificiais. Considera-se, como fator importante, o grande numero de recipientes descartaveis produzidos atualmente e que podem aumentar o numero de criadouros viaveis para mosquitos culicideos.

Primeiro encontro de Aedes (Stegomyia) Albopictus (Skuse) no Estado de São Paulo (Brasil)

A Superintendencia de Controle de Endemias (SUCEN), por intermedio do Programa de Controle da Febre Amarela e Dengue, desenvolve atividades no sentido de detectar a presenca de Aedes aegypti (Linnaeus), no Estado de Sao Paulo. Considerando a importância de outras especies de culicideos na transmissao destas doencas, e a presenca de Aedes albopictus (Skuse) nos Estados do Rio de Janeiro, Espirito Santo e Minas Gerais foi intensificado o trabalho de vigilância desse vetor.

Método de varredura para exame de criadouros de vetores de dengue e febre amarela urbana

Com objetivo de estimar o numero minimo de varreduras para coletar uma amostra representativa das larvas presentes em um grande recipiente, foram adicionadas 200 larvas de quarto estadio em um tambor de 80 litros de agua. Com auxilio de peneira plastica, foram feitas dez varreduras em cada replica do experimento. Os resultados indicaram que oito varreduras foram suficientes para coletar ate 72% do total de 200 larvas de quarto estadio presentes no criadouro, ou seja, uma media de 143±1,97. A tecnica mostrou ser de facil e eficiente execucao quanto a inspecao de criadouros com grande volume de agua. Isto reforca sua utilizacao como instrumento com grande potencial para vigilância vetorial na rotina dos programas de controle de vetores do dengue e febre amarela.

Novos encontros de anofelíneos em recipientes artificiais

New findings of Anopheles mosquitoes in artificial containers are reported. In one, a plastic container served as a breeding place for Anopheles bellator larvae and, in another, four instar larvae of An. albitarsis s.l. were found in an abandoned toilet basin. Reflections are offered as to the selective pressure represented by the production, of an ever increasing scale, of disposable objects.

Produtividade de criadouros de Aedes albopictus no Vale do Paraíba, SP, Brasil

OBJECTIVE To estimate the potential productivity of artificial, permanent, and natural breeding containers of Aedes albopictus, potential vector species of dengue. METHODS Three locations were selected for this study: a) warehouse of disposable material goods in the urban area of Pindamonhangaba, state of São Paulo, Brazil; b) a small leisure farmland in Tremembé, state of São Paulo; and c) residual forest in the periurban area of Pindamonhangaba. All breeding containers were assessed and classified according to their water volume ( small (up to 1 liter), medium (over 1 but up to 10 liters), and large (over 10 liters), and type (artificial, natural, and permanent). Collections were carried out fortnightly for a period of 12 months, and a sample of fourth-instar larvae and pupae were collected from each container. Statistical analysis was performed using the Kriskal-Wallis test, t-Student test, and emergence estimate. RESULTS The statistical analyses and emergence estimate (E) showed that artificial large-size containers and permanent medium container were on average the most productive, resulting 2.8 females a day, each. Natural small and medium containers produced on average 0.5 and 0.6 females respectively. CONCLUSIONS There is a need for further studies on the potential productivity of containers not only of Ae. albopictus but also of Aedes aegypti, the main vector of dengue, which could contribute to better assessments of population densities in surveillance and control programs.

Microhabitats of Aedes albopictus (Skuse) in the Paraíba Valley region of the State of S. Paulo, Brazil

The objective of this study was the determination of extent of the spatial distribution of Aedes albopictus in the Paraiba 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 Paraiba 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.