Encontro de imaturos de Anopheles cruzii em bromélias de área urbana, litoral de São Paulo / Anopheles cruzii larvae found in bromelias in an urban area on the Brazilian coast

Primeiro relato da ocorrência de larvas de Anopheles (Kerteszia) cruzii, mosquito essencialmente silvestre, em bromélias de solo em área urbana do município de Ilhabela, litoral norte do estado de São Paulo. De março de 1998 a julho de 1999 foram capturadas 312 formas imaturas de An. cruzii, sendo 8,6 por cento em bromélias do ambiente urbano, 40,1 por cento em bromélias do periurbano e 51,3 por cento na mata. O número médio de bromélias com An. cruzii foi de 4,0 por cento dentre o total de pesquisadas, com valores próximos de positividade para ambiente periurbano e mata. A presença de An. cruzii no ambiente urbano provavelmente é resultante da sua ocorrência prévia na mata, aliada à elevada presença desse criadouro na área urbana, de fonte alimentar e abrigos disponíveis. Alerta-se para a possibilidade de transferência de infecções entre esses ambientes.

The occurrence of Anopheles (Kerteszia) cruzii larvae is reported for the first time in bromelias on the ground located in an urban area within the municipality of Ilha Bela, on the northern coast of the State of São Paulo. From March 1998 to July 1999 312 immature forms of An. cruzii were captured, being that 8.6 percent of them were in bromelias in the urban environment, 40.1 percent in periurban bromelias and 51.3 percent in the forest. The average number of bromelias containing An. cruzii was 4.0 percent of the total investigated. The positive rate in the periurban and forested environments presented similar values. The presence of An. cruzii is probably due to their having been present previously in the forest, together with the frequent presence of these breeding places, food sources and appropriate shelter in the urban area. This set of factors makes it necessary to warn against the possibility of transferring infections from one environment to the other.

Primer relato de la presencia de larvas de Anopheles (Kerteszia) cruzii, mosquito esencialmente silvestre, en bromelias de suelo en área urbana del municipio de Ilhabela, litoral norte del estado de São Paulo (Sureste de Brasil). De marzo de 1998 a julio de 1999 fueron capturadas 312 formas inmaduras de An. cruzii, siendo 8,6 por ciento en bromelias del ambiente urbano, 40,1 por ciento en bromelias del periurbano, y 51,3 por ciento en la selva. El número prmedio de bromelias con An. cruzii fue de 4,0 por ciento del total de evaluadas, con valores próximos de positividad para ambiente periurbano y selva. La presencia de An. cruzii en el ambiente urbano probablemente es resultante de su ocurrencia previa en la selva, aliado a la elevada presencia de criaderos en el área urbana, de fuente de alimentación y abrigos disponibles. Se alerta la posibilidad de transferencia de infecciones entre esos ambiente.

[Anopheles cruzii larvae found in bromelias in an urban area on the Brazilian coast]. / Encontro de imaturos de Anopheles cruzii em bromélias de área urbana, litoral de São Paulo.

The occurrence of Anopheles (Kerteszia) cruzii larvae is reported for the first time in bromelias on the ground located in an urban area within the municipality of Ilha Bela, on the northern coast of the State of São Paulo. From March 1998 to July 1999 312 immature forms of An. cruzii were captured, being that 8.6% of them were in bromelias in the urban environment, 40.1% in periurban bromelias and 51.3% in the forest. The average number of bromelias containing An. cruzii was 4.0% of the total investigated. The positive rate in the periurban and forested environments presented similar values. The presence of An. cruzii is probably due to their having been present previously in the forest, together with the frequent presence of these breeding places, food sources and appropriate shelter in the urban area. This set of factors makes it necessary to warn against the possibility of transferring infections from one environment to the other.

Culicídeos em bromélias: diversidade de fauna segundo influência antrópica, litoral de São Paulo / Culícidos en bromelias: diversidad de fauna según influencia antrópica, litoral de Brasil / Culicidae in bromeliads: diversity of species by anthropic environments, coastal area of Southeastern Brazil

OBJETIVO: Comparar a diversidade da fauna de culicídeos em bromélias de solo segundo ambientes urbano, periurbano e mata primitiva. MÉTODOS: O estudo foi realizado no município de Ilhabela, litoral norte do estado de São Paulo, em tanques de bromélias de ambientes urbano, periurbano e mata. Realizaram-se coletas de imaturos quinzenalmente, de março de 1998 a julho de 1999. A presença e freqüência de espécies nos diferentes ambientes foram comparadas com base em estimativas da diversidade para medir a riqueza, dominância e análise de variância (ANOVA). RESULTADOS: Coletaram-se 31.134 formas imaturas de mosquitos nas bromélias, distribuídas em sete gêneros e 37 espécies. O ambiente urbano registrou maior abundância, 14.575 indivíduos, seguido do periurbano com 10.987, e a mata, com o menor número de exemplares, 5.572. Foram coletadas 30 espécies no habitat urbano, 32 no periurbano e 33 na mata. As espécies dominantes foram Culex (Microculex) pleuristriatus nos ambientes urbano e periurbano, e Culex ocellatus na mata. De acordo com teste ANOVA a freqüência de mosquitos em bromélias não foi diferente entre os ambientes pesquisados (F=0,5564; p=0,5769). A diversidade de espécies na mata foi maior, e semelhante entre periurbano e urbano...

OBJECTIVE: To compare diversity of Culicidae species collected from ground bromeliads in an urban, and periurban area and primitive forest. METHODS: Study carried out in the city of Ilhabela, northern stretch of the coast of the State of São Paulo, Southeastern Brazil, from March 1998 to July 1999. Fortnightly immature Culicidae collections were undertaken in bromeliad tanks located in urban, and periurban areas, and primitive forest. The frequencies of species collected in the different environments were compared based on the estimated diversity to assess their richness, dominance and variance (ANOVA). RESULTS: A total of 31,134 immature mosquitoes from seven different genera and 37 species were collected from ground bromeliads. The urban environment had the greatest abundance (14,575 specimens), followed by the periurban (10,987) and then the forest environment (5,572). There were collected 30 species in the urban habitat, 32 in the periurban and 33 in the forest. The most dominant species were: Culex (Microculex) pleuristriatus in the urban and periurban areas, and Culex ocellatus in the forest. There was no difference in the frequency of mosquitoes in bromeliads in the different environments studied using ANOVA (F=0.5564; p=0.5769). The diversity of immature mosquitoes was greater in the forest and similar in the urban and periurban environments...

OBJETIVO: Comparar la diversidad de la fauna de culícidos en bromelias de suelo según ambientes urbano, periurbano y selva virgen. MÉTODOS: El estudio fue realizado en el municipio de Ilhabela, litoral norte del estado de Sao Paulo (Sureste de Brasil), en tanques de bromelias de ambientes urbano, periurbano y selva virgen. Se realizaron colectas de inmaduros quincenalmente, de marzo de 1998 a julio de 1999. La presencia y frecuencia de especies en los diferentes ambientes fueron comparadas con base en estimaciones de la diversidad para medir la riqueza, dominancia y análisis de varianza (ANOVA). RESULTADOS: Se colectaron 31.134 formas inmaduras de mosquitos en las bromelias, distribuidas en siete géneros y 37 especies. El ambiente urbano registró mayor abundancia, 14.575 individuos, seguido del periurbano con 10.987, y la selva virgen, con el menor número de ejemplares, 5.572. Fueron colectadas 30 especies en el habitat urbano, 32 en el periurbano y 33 en la selva. Las especies dominantes fueron Culex (Microculex) pleuristriatus en los ambientes urbano y perirurbano, y Culex ocellatus en la selva. De acuerdo con el test de ANOVA la frecuencia de mosquitos en bromelias no fue diferente entre los ambientes investigados (F=0,5564; p=0,5769). La diversidad de especies en la selva fue mayor, y semejante entre el periurbano y el urbano...

[Culicidae in bromeliads: diversity of species by anthropic environments, coastal area of Southeastern Brazil]. / Culicídeos em bromélias: diversidade de fauna segundo influência antrópica, litoral de São Paulo.

OBJECTIVE: To compare diversity of Culicidae species collected from ground bromeliads in an urban, and periurban area and primitive forest. METHODS: Study carried out in the city of Ilhabela, northern stretch of the coast of the State of São Paulo, Southeastern Brazil, from March 1998 to July 1999. Fortnightly immature Culicidae collections were undertaken in bromeliad tanks located in urban, and periurban areas, and primitive forest. The frequencies of species collected in the different environments were compared based on the estimated diversity to assess their richness, dominance and variance (ANOVA). RESULTS: A total of 31,134 immature mosquitoes from seven different genera and 37 species were collected from ground bromeliads. The urban environment had the greatest abundance (14,575 specimens), followed by the periurban (10,987) and then the forest environment (5,572). There were collected 30 species in the urban habitat, 32 in the periurban and 33 in the forest. The most dominant species were: Culex (Microculex) pleuristriatus in the urban and periurban areas, and Culex ocellatus in the forest. There was no difference in the frequency of mosquitoes in bromeliads in the different environments studied using ANOVA (F=0.5564; p=0.5769). The diversity of immature mosquitoes was greater in the forest and similar in the urban and periurban environments. CONCLUSIONS: The specific composition of Culicidae mosquitoes in ground bromeliads was greatly diversified and higher in those located in the forest environment. Cx. (Mcx.) pleuristriatus and Cx. ocellatus were the dominant species.

Distribuição vertical e sazonal de Anopheles (Kerteszia) em Ilha Comprida, SP / Vertical and seasonal distribution of Anopheles (Kerteszia) in Ilha Comprida, Southeastern Brazil

OBJETIVO: Anopheles bellator e An. cruzii são vetores da malária-bromélia, característicos de áreas preservadas. O objetivo do estudo foi analisar a distribuição sazonal e vertical desses anofelinos, visando contribuir para a avaliação do risco de transmissão desse agravo. MÉTODOS: No município de Ilha Comprida, SP, foram instaladas armadilhas luminosas tipo CDC iscadas com gelo seco, das 17 às 20h, a um, seis e 12m do solo, quinzenalmente, de setembro de 2001 a setembro de 2002. A relação da densidade desses anofelinos com o clima foi avaliada pelo coeficiente de Spearman e suas densidades entre os estratos foram comparadas pelo teste não paramétrico de Mann-Whitney. RESULTADOS: Do total de 55.226 mosquitos, 1.341 eram An. bellator (2,4 por cento do total de Culicidae), sendo capturados 278 indivíduos próximo ao solo, 261 a seis metros e 802 na copa (12 m). Na mesma ordem, foram capturados 452, 1.032 e 4.420 adultos de An. cruzii, totalizando 5.904 mosquitos desta espécie (10,7 por cento). Houve correlação positiva entre a densidade das duas espécies com a temperatura máxima, e entre An. bellator e amplitude térmica diária. As densidades das duas espécies foram maiores na copa. Nos três estratos, An. cruzii predominou sobre An. bellator. CONCLUSÕES: Confirmou-se o comportamento acrodendrófilo dessas espécies, principalmente An. cruzii. Após medidas drásticas de controle, esses anofelinos permaneceram na região mas, atualmente, não são alvo de vigilância entomológica. A persistência da transmissão de malária autóctone e o incremento de atividades de ecoturismo na região apontam a necessidade de monitoramento dessas espécies.

OBJECTIVE: Anopheles bellator e An. cruzii are vectors of the so-called bromeliad-malaria, typical of conserved areas. The objective was to evaluate the seasonal and vertical distribution of these anophelines, aiming at assessing the risk of malaria transmission. METHODS: In the municipality of Ilha Comprida, Southeastern Brazil, CDC light traps baited with dry ice were placed fortnightly from 17:00 to 20:00, at one, six and 12 meters high from September 2001 to September 2002. Association between An. bellator and An. cruzii densities and weather were assessed by Spearman coefficient and comparisons among heights and species densities were made by Mann-Whitney non-parametric test. RESULTS: A total of 55,226 mosquitoes were caught: 1,341 were An. bellator (2.4 percent of Culicidae), 278 at one meter, 261 at six meter and 802 at 12m high. Following the same sequence, An. cruzii was represented by 452, 1,032 and 4,420 adults, totalizing 5,904 mosquitoes (10.7 percent). There was a positive correlation between densities of both species and daily maximum temperature, and between density of An. bellator and thermal amplitude. The densities were higher for both species at tree canopy. At the three levels, the density of An. cruzii was higher. CONCLUSIONS: The acrodendrophilic behavior of these species was confirmed, remarkably in An. cruzii. After aggressive measures of control, these anophelines have remained in this region, but they are not under entomological surveillance. The persistent transmission of malaria and increasing tourism activities in this region highlight the need for surveillance of these species.

[Vertical and seasonal distribution of Anopheles (Kerteszia) in Ilha Comprida, Southeastern Brazil]. / Distribuição vertical e sazonal de Anopheles (Kerteszia) em Ilha Comprida, SP.

OBJECTIVE: Anopheles bellator e An. cruzii are vectors of the so-called bromeliad-malaria, typical of conserved areas. The objective was to evaluate the seasonal and vertical distribution of these anophelines, aiming at assessing the risk of malaria transmission. METHODS: In the municipality of Ilha Comprida, Southeastern Brazil, CDC light traps baited with dry ice were placed fortnightly from 17:00 to 20:00, at one, six and 12 meters high from September 2001 to September 2002. Association between An. bellator and An. cruzii densities and weather were assessed by Spearman coefficient and comparisons among heights and species densities were made by Mann-Whitney non-parametric test. RESULTS: A total of 55,226 mosquitoes were caught: 1,341 were An. bellator (2.4% of Culicidae), 278 at one meter, 261 at six meter and 802 at 12m high. Following the same sequence, An. cruzii was represented by 452, 1,032 and 4,420 adults, totalizing 5,904 mosquitoes (10.7%). There was a positive correlation between densities of both species and daily maximum temperature, and between density of An. bellator and thermal amplitude. The densities were higher for both species at tree canopy. At the three levels, the density of An. cruzii was higher. CONCLUSIONS: The acrodendrophilic behavior of these species was confirmed, remarkably in An. cruzii. After aggressive measures of control, these anophelines have remained in this region, but they are not under entomological surveillance. The persistent transmission of malaria and increasing tourism activities in this region highlight the need for surveillance of these species.

[Biogeography, origin, and distribution of triatominae domiciliarity in Brazil. Revista de Saúde Pública, 14(3):265-99, 1980]. / Biogeografia, origem e distribuição da domiciliação de triatomíneos no Brasil. Revista de Saúde Pública, 14:265-99, 1980.

An association is established between the Brazilian geographical pattern of the domiciliarity of the triatominae bugs and open lands characterized by natural savanna vegetation or artificial, man-made landscapes. The Brazilian open lands involved are the "caatingas'' and "cerrados", both wholly included in Brazilian territory, while the mixed Southern subtropical prairies belong to systems extending bevond national boundary lines. The other open lands are anthropic-lands opened mainly by the destruction of primitive forests of the tropical Atlantic system. Attempts were made to subject the four synanthropic species of epidemiological importance to model paleoecologic refuges and endemic centers. Triatoma sordida, Triatoma brasiliensis, and Triatoma pseudomaculata seem to have their endemic centers in the "cerrados" and "caatinga", while the Panstrongylus megistus may have originated in the tropical Atlantic forest system. The Triatoma infestans, however, seem to have originated in Bolivia, then were spread to large dispersal regions by man. Thus it can be assumed that domiciliarity is arrived at through an opportunistic mechanism stimulated by shelter and food availability factors. Once established, domiciliarity favors the species survival and dispersal, and this is of particular interest to control and surveillance programs because it increases the probability of the triatominae's success in synanthropic specialization. The present intense anthropic activities in the Amazonian system will lead to even greater expansion into the open lands; consequently, a triatominae domiciliarity spread can be expected, due to either autochthonous or man-introduced populations. A public health problem will then arise in a region where it has, heretofore, been unknown.

Biogeografia, origem e distribuição da domiciliação de triatomíneos no Brasil / Biogeography, origin, and distribution of triatominae domiciliarity in Brazil

Considerando a distribuição atual da domicialiação triatomínea no Brasil, pode-se verificar sua associação com a referente aos espaços abertos. Estes podem ser considerados como naturais e artificiais. Os primeiros estão essencialmente situados nos domínios paisagísticos das caatingas, dos cerrados, totalmente incluídos em território brasileiro, e das pradarias mistas subtropicais pertencentes a paisagem que se estende além desses limites. Os outros são os originados da ação antrópica resultando em expansão da paisagem aberta principalmente em virtude da devastação da cobertura florestal do domínio tropical atlântico. Embora tentativamente, procurou-se aplicar o modelo de refúgios paleoecológicos e da existência de centros de endemismo às quatro espécies de domiciliação epidemiologicamente significante. O Triatoma sordida, Triatoma brasiliensis e Triatoma pseudomaculata parece ter seus centros de endemismo nos espaços abertos dos cerrados e das caatingas, enquanto o Panstrongylus megistus teria tido sua origem nas florestas do ambiente tropical atlântico. Quanto ao Triatoma infestans, sua área endêmica estaria localizada em território boliviano, de onde se dispersou e continua se dispersando pela ação do homem. A invasão domiciliar, ao que tudo indica, obedece a mecanismo oportunista propiciado por vários estímulos de abrigo e alimentação. Uma vez instalada, a domiciliação permite não apenas a sobrevivência, mas também a dispersão da espécie. Esses conceitos devem ser levados em conta nas campanhas de controle, uma vez que a probabilidade de sucesso aumenta com essa especialização do triatomíneo. A continuidade da ação antrópica sobre o ambiente, atualmente intensificada na região do domínio equatorial amazônico, resultará na expansão dos espaços abertos. Assim sendo, seja a custa de espécies locais seja a custa de espécies introduzidas, poderá ocorrer a domiciliação triatomínea, como problema de saúde pública, em região onde ainda não foi assinalada.

An association is established between the Brazilian geographical pattern of the domiciliarity of the triatominae bugs and open lands characterized by natural savanna vegetation or artificial, man-made landscapes. The Brazilian open lands involved are the "caatingas'' and "cerrados", both wholly included in Brazilian territory, while the mixed Southern subtropical prairies belong to systems extending bevond national boundary lines. The other open lands are anthropic-lands opened mainly by the destruction of primitive forests of the tropical Atlantic system. Attempts were made to subject the four synanthropic species of epidemiological importance to model paleoecologic refuges and endemic centers. Triatoma sordida, Triatoma brasiliensis, and Triatoma pseudomaculata seem to have their endemic centers in the "cerrados" and "caatinga", while the Panstrongylus megistus may have originated in the tropical Atlantic forest system. The Triatoma infestans, however, seem to have originated in Bolivia, then were spread to large dispersal regions by man. Thus it can be assumed that domiciliarity is arrived at through an opportunistic mechanism stimulated by shelter and food availability factors. Once established, domiciliarity favors the species survival and dispersal, and this is of particular interest to control and surveillance programs because it increases the probability of the triatominae's success in synanthropic specialization. The present intense anthropic activities in the Amazonian system will lead to even greater expansion into the open lands; consequently, a triatominae domiciliarity spread can be expected, due to either autochthonous or man-introduced populations. A public health problem will then arise in a region where it has, heretofore, been unknown.

[Aedes albopictus in soil bromeliads in Ilhabela, coastal area of Southeastern Brazil]. / Aedes albopictus em bromélias de solo em Ilhabela, litoral do Estado de São Paulo.

OBJECTIVE: To analyze the presence of Aedes albopictus in soil bromeliads in ecologically distinct environments in terms of positivity, density and volume of water. METHODS: The study was carried out in the municipality of Ilhabela, North coast of the state of São Paulo, Brazil. Collections were fortnightly performed between March 1998 and July 1999, in containers of bromeliads located in urban, peri-urban and forest environments. The water content in plants was measured and recorded. Data analysis was based on the frequency of bromeliads with Ae. albopictus (ANOVA), abundance (Kruskal-Wallis) and volume of water in positive bromeliads (Student's t-test). RESULTS: The presence and density of Ae. albopictus in soil bromeliads varied by environment. Greater positivity (85%) and abundance (81%) were found in plants located in the urban environment. Also, mosquitoes showed preference to bromeliads with higher content of water (mean 300 ml). CONCLUSIONS: The different frequencies and densities of Ae. albopictus seen in the different environments show their capacity of invading new habitats. It is advisable to intensify entomologic surveillance in these plants as they could become permanent breeding sites. The presence of these mosquitoes of medical importance in bromeliads in a preserved area of the Atlantic Rainforest may imply in serious health hazard.

Aedes albopictus em bromélias de solo em Ilhabela, litoral do Estado de São Paulo / Aedes albopictus in soil bromeliads in Ilhabela, coastal area of Southeastern Brazil

OBJETIVO: Analisar a presença de Aedes albopictus em bromélias de solo localizadas em ambientes ecologicamente distintos, em termos de positividade, densidade e volume de água. MÉTODOS: O estudo foi realizado no município de Ilhabela, litoral norte do Estado de São Paulo. Realizaram-se coletas quinzenais, de março de 1998 a julho de 1999, em tanques de bromélias localizadas nos ambientes urbano, periurbano e mata; o conteúdo aquático das plantas foi medido e registrado. O tratamento dos dados baseou-se na análise da freqüência de bromélias com presença de Ae. albopictus (ANOVA), abundância (Kruskal-Wallis) e volume de água das bromélias positivas (Teste t de Student). RESULTADOS: A presença e a densidade de Ae. albopictus em bromélias de solo variou com o tipo de ambiente. Os maiores percentuais de positividade (85 por cento) e abundância (81 por cento) foram observados nas plantas localizadas em ambiente urbano. Constatou-se ainda preferência dos mosquitos pelas bromélias com maiores volumes de água (média de 300 ml). CONCLUSÕES: As diferentes freqüências com que Ae. albopictus foi registrado nos ambientes e suas respectivas densidades mostraram sua capacidade de invasão a novos habitats. Recomenda-se intensificar a vigilância entomológica nessas plantas, dada a sua capacidade em traduzir-se em criadouros permanentes. A presença desse mosquito de importância médica em bromélias em área preservada da Mata Atlântica poderá resultar em agravo à saúde.

Karyotype of Brazilian Anopheles albitarsis sensu lato (Diptera:Culicidae).

Anopheles (Nyssorhynchus) albitarsis sensu lato is an important malaria vector in Brazil, especially in the Brazilian Amazon region. Chromosome preparations of fourth-instar larvae of A. albitarsis from Iranduba and Coari (AM) and Ilha Comprida (SP) were analyzed for karyotype determination and to improve cytogenetic identification of this species. Anopheles albitarsis possesses 2n = 6 chromosomes, with two pairs (submetacentric and metacentric) of autosomes and one pair of sex chromosomes, with X-Y dimorphism. The sex pair is homomorphic and acrocentric in females and heteromorphic in males, with a punctiform Y chromosome. Somatic pairing was detected in the prometaphase and metaphase chromosomes of the three A. albitarsis populations. Apparently, sex chromosome evolution in the Culicidae does not function as does evolution in the Culicidae, since it occurs in the subfamily Anophelinae, which possesses heteromorphic sex chromosomes and is regarded as primitive, based on several criteria. These karyotype data on the albitarsis complex reinforce the hypothesis that sex chromosome evolution in the subfamily Anophelinae is conserved, and the variation revealed in the mean size of chromosomes in three populations indicates that selective pressure in these populations is occurring only at a genetic level.

Susceptibility of urban and rural populations of Aedes albopictus from São Paulo State, Brazil, to infection by dengue-1 and -2 viruses.

In Brazil, dengue viruses (DENV) are transmitted by Aedes aegypti (L.). However, the recent introduction of Aedes albopictus (Skuse) has caused concern, because some populations of this species also are capable of DENV transmission. Ae. albopictus from rural and urban localities of São Paulo State, Brazil, were artificially exposed to infection with DENV-1 and -2 to evaluate their susceptibility. The rates of infection (6.2 and 5.7% for DENV-1; 5.3 and 12% for DENV-2) and dissemination (22.2 and 40% for DENV-1; 0 and 20% for DENV-2) were low in both urban and rural populations, with no significant differences detected between these mosquito populations.

Anopheles albitarsis s.l. (Diptera: Culicidae) survivorship and density in a rice irrigation area of the state of São Paulo, Brazil.

Collections of Anopheles albitarsis Arribalzaga s.l. were conducted from May 1996 to June 2000 to estimate the human biting rate, and mark-release-recapture experiments were carried out to estimate the daily survival probability. The density of An. albitarsis females showed a marked seasonal variation, with peaks as high as 629 individuals per human per night in the wet season. The low daily survival probability of 0.61 is an important factor limiting the vectorial capacity of An. albitarsis s.l. in southeastern Brazil.

[Productivity of Aedes albopictus' breeding containers in Paraíba Valley, Brazil]. / 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.

Produtividade de criadouros de Aedes albopictus no Vale do Paraíba, SP, Brasil / Productivity of Aedes albopictus breeding containers in Paraíba Valley, Brazil

OBJETIVO: Estudar o potencial de produtividade de criadouros artificiais, permanentes e naturais de Aedes albopictus, espécie considerada vetor potencial de dengue. MÉTODOS: O estudo foi desenvolvido nos municípios de Tremembé e Pindamonhangaba, Estado de São Paulo, em três locais selecionados: a) imóvel com atividades comerciais de compra e venda de materiais e recipientes descartáveis, em área urbana; b) chácara de lazer; c) mata de caráter residual. Realizou-se levantamento dos criadouros existentes em cada local, classificados quanto ao seu tamanho (volume de água) - pequeno (até um litro), médio (acima de um até 10 litros) e grande (acima de 10 litros) - e quanto ao tipo: artificial, natural e permanente. Foram executadas coletas em intervalos quinzenais por um período de 12 meses, retirando-se larvas de quarto estádio e pupas em cada tipo de criadouro existente. Para análise dos resultados, foram usados os testes de Kriskal-Wallis, t de Student e o cálculo de emergência. RESULTADOS: Segundo as análises estatísticas e o cálculo de emergência (E), os criadouros artificiais grande e o permanente médio foram, em média, mais produtivos para Aedes albopictus, contribuindo com 2,8 fêmeas por dia, cada. E os criadouros naturais pequenos e médios tiveram produção média diária de 0,5 e 0,6 fêmeas, respectivamente. CONCLUSÕES: Os resultados indicam a necessidade de se realizarem estudos sobre o potencial de produtividade de criadouros não somente de Ae. albopictus, mas sobretudo de Aedes aegypti, principal vetor de dengue, o que poderia contribuir para o aprimoramento das avaliações das densidades populacionais, nos programas de vigilância e controle.

[Household water reservoirs and control of Aedes aegypti]. / 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.

Reservatórios domiciliares de água e controle do Aedes aegypti / Household water reservoirs and control of Aedes aegypti

Os reservatórios domiciliares de água, comumente conhecidos como caixas d'água, constituem fonte de desenvolvimento do Aedes aegypti. Em áreas com edificações precárias existe tendência para situar essas caixas sobre a laje das casas. Todavia, observa-se na arquitetura moderna a mesma situaçäo em relaçäo a esses recipientes, mesmo em condomínios de luxo. Assim sendo, chama-se a atençäo para a necessidade de, na vigilância entomológica, ter cuidado especial para tais reservatórios domiciliares de água.

[Parity and wind impact on the frequency of Anopheles marajoara, São Paulo, Brazil]. / Paridade e influência do vento sobre a freqüência de Anopheles marajoara, São Paulo.

OBJECTIVE: To evaluate the impact of wind velocity on the behavior of An. marajoara population and its parity. METHODS: Collections were made bimonthly from January 1999 to February 2000 in the municipality of Ilha Comprida, Brazil. Adult mosquitoes were captured with a battery hand aspirator. Mann-Whitney test was applied to verify the wind impact on mosquito behavior. Polovodova technique and Christophers and Mer's follicular development analysis were used to determine parity. RESULTS: A total of 11,833 mosquitoes were captured, including 3,072 An. marajoara specimens. The peak of activity of An. marajoara occurred from 2 to 5 AM. Amongst 1,006 An. marajoara females who had their ovarioles dissected, it was found 530 (52.7%) nulliparous, 432 (42.9%) uniparous, 24 (2.4%) biparous and 1 multiparous. According to Christophers and Mer analysis, 982 (97.6%) had their follicles in phases I and II, 7 in phases III and IV, and 17 in phase V. The frequency of An. marajoara was significantly lower when wind velocity was 3 km/h or more or below 3 km/h. CONCLUSIONS: An. marajoara mosquitoes were more active at night. About 50% of dissected An. marajoara females were oniparous. Another important finding was the high proportion of females (97.6%) with follicles in the Christophers and Mer's phases I and II, suggesting the presence of gonotrophic concordance. Wind velocity equal or higher than 3 km/h considerably reduced the frequency of An. marajoara.