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1.
Acta Trop ; 221: 106009, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34126089

RESUMO

São Paulo is one of the largest cities in the world and has several characteristics that favor a diversity of urban and wild mosquitoes. Little is known about how variations in mosquito diversity and feeding preferences for different hosts in different vegetation strata can influence the risk of pathogen transmission to humans. We investigated vertical stratification of mosquitoes and its relationship with vertebrate hosts in environments with different degrees of conservation in two conservation units in the city of São Paulo. Adult mosquitoes were collected using CDC traps, aspiration and Shannon traps. After morphological identification, host blood in engorged females was analyzed by PCR with a vertebrate-specific primer set based on mitochondrial cytochrome b DNA of vertebrates commonly found in the two conservation units. Although a higher abundance of the species Anopheles cruzii and Culex nigripalpus was found in the canopy, blood not only from birds but also from humans and rodents was identified in these mosquitoes. In one of the units, Wyeomyia confusa and Limatus durhamii were found occupying mainly niches at ground level while Culex vaxus was frequently found in the canopy. Haemagogus leucocelaenus, the main vector of yellow fever, was found in low abundance at all collection points, particularly in the canopy. Species richness and composition tended to vary little between canopy and ground level in the same environment, but the abundance between canopy and ground level varied more depending on the species analyzed, the most abundant and frequent species exhibiting a predilection for the canopy. Even those mosquito species observed more frequently in the canopy did not show an association with hosts found in this stratum as most of the blood identified in these species was from humans, suggesting opportunist feeding behavior, i.e., feeding on the most readily available host in the environment. The two most common species in the study, An. cruzii and Cx. nigripalpus, may be able to act as bridge vectors for pathogens to circulate between the forest canopy and ground level.


Assuntos
Anopheles , Culex , Culicidae , Ecossistema , Animais , Brasil , Cidades , Comportamento Alimentar , Feminino , Mosquitos Vetores
2.
Acta Trop ; 205: 105413, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32088278

RESUMO

Kerteszia is a neotropical subgenus of Anopheles composed of 12 species. The species in this subgenus are strongly associated with humid forests rich in epiphytic bromeliads. Forest fragmentation and anthropogenic changes can therefore have a negative impact on the abundance and survival of these mosquito species. Within this subgenus, four species are considered primary vectors of malaria: An. cruzii, An. bellator, An. homunculus and An. neivai. Malaria cases associated with Kerteszia species are often referred to as bromeliad malaria, a type of malaria reported to be endemic in the coastal rainforest of the neotropical region since the end of the nineteenth century. Although the incidence of bromeliad-malaria cases has decreased since the middle of the last century, autochthonous malaria cases continue to be registered every year. The complexity of the epidemiology of bromeliad malaria appears to be increasing as asymptomatic plasmodial infections and transmission of simian Plasmodium to humans have recently been reported. Kerteszia vector species have a great affinity for human beings and can be found in human-modified areas close to forest fragments such as in the Extra-Amazonian region of Brazil, Colombian pacific coast, and the Caribbean coast. Deforestation and forest fragmentation have been occurring continuously in the biomes of the neotropical region, and findings of Kerteszia species in dwellings are frequent in this region. Controlling the species in the Kerteszia subgenus is particularly difficult because they move frequently from natural to rural and peri-urban areas in search of blood sources, posing a challenge for the development of control strategies based on integrated vector management. Furthermore, as it has been shown that some Kerteszia species share similar morphological and genetic characteristics, the existence of a species complex formed by cryptic, sibling species within the Kerteszia group in different areas in the South and Southeast of Brazil cannot be ruled out. The existence of such a complex could represent an obstacle to the control of Kerteszia species and consequently to the elimination of bromeliad-malaria transmission in these regions. Here, we review publications that focus on the biology and ecology of Kerteszia malaria vectors and their association with human-modified areas and bromeliad-malaria transmission.


Assuntos
Anopheles/genética , Anopheles/parasitologia , Malária/transmissão , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Animais , Anopheles/fisiologia , Brasil/epidemiologia , Região do Caribe , Vetores de Doenças , Atividades Humanas , Humanos , Malária/epidemiologia , Floresta Úmida , Fatores de Risco , Especificidade da Espécie
3.
Trends Parasitol ; 35(6): 383-387, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31006599

RESUMO

Extra-Amazonian malaria has been reported to be endemic in Brazil since the end of the 19th century. Currently, only a few cases are reported annually. However, recent findings of unexpected Plasmodium infections with uncertain transmission cycles in the Extra-Amazonian region could pose a threat to the malaria elimination agenda in Brazil.


Assuntos
Erradicação de Doenças/tendências , Malária/prevenção & controle , Malária/transmissão , Animais , Brasil , Erradicação de Doenças/estatística & dados numéricos , Humanos , Malária/parasitologia , Plasmodium/fisiologia , Pesquisa/tendências
4.
J Med Entomol ; 53(4): 790-797, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27146682

RESUMO

Mitochondrial genome sequences are widely used as molecular markers for phylogenetic studies of mosquito species complexes, such as the Anopheles albitarsis complex. Except for a few studies that employed a limited number of nuclear or mitochondrial loci to address the genetic structure and species status of Anopheles cruzii, Anopheles bellator, and Anopheles homunculus, little is known about genetic markers that can be employed in studies focusing on Kerteszia species. The complete mitochondrial genomes of seven specimens of An. bellator, An. cruzii, An. homunculus, and Anopheles laneanus were sequenced using long-range polymerase chain reaction and Illumina sequencing. The mitochondrial genomes varied from 15,446 to 15,738 bp in length and contained 37 genes (13 protein-encoding genes, 2 rRNA genes [12S rRNA and 16S rRNA] and 22 tRNA genes), and the AT-rich control region, as all do other Anopheles mitochondrial genomes sequenced to date. Specimens from four populations of An. cruzii showed differences in codon composition.


Assuntos
Anopheles/genética , Genoma de Inseto , Genoma Mitocondrial , Animais , Brasil , Feminino , Masculino , Análise de Sequência de DNA
5.
Acta Trop ; 164: 303-313, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27686960

RESUMO

On the ecological scale of an organism, a homogeneous geographical landscape can represent a mosaic of heterogeneous landscapes. The bionomy of Kerteszia mosquitoes can contribute to foundation landscape ecology by virtue of in the role of the configuration and composition of the habitat played in the distribution of mosquito species. Thus, this study aimed: to compare the abundance of Kerteszia in dense tropical rainforest, restinga and rural area, to assess the bioecological characteristics of the main bromeliads hosting Kerteszia, and to associate the bioecological arrangement of the bromeliads with Kerteszia distribution. Field collections were conducted in a monthly schedule from December of 2010 to November 2011. The vegetation of landscapes was characterized on the basis of a digital cartographic database, the manual of the Brazilian vegetation, environmental atlas information, satellite images and visits to the sites. Multivariate generalized linear models were employed using the R-project statistical program. The results were: Anopheles cruzii was the most frequent species in dense tropical rainforest (67.42%), with a positive association (deviance=25.8; P=0.002). Anopheles bellator was more abundant in the Restinga area (78.97%), with a positive association (deviance=10.4, P=0.018). There was a positive aggregation of Restinga with An. bellator (RR=2.42) but a lower level with An. cruzii (RR=0.31). Thus we can conclude that landscape characteristics influence the distribution of Kerteszia mosquitoes. An. bellator has a higher prevalence in Restinga areas, whereas An. cruzii was the most prevalent in the dense tropical rainforest.


Assuntos
Anopheles/crescimento & desenvolvimento , Bromelia/crescimento & desenvolvimento , Ecossistema , Floresta Úmida , Animais , Biometria , Brasil
6.
Neotrop. entomol ; 38(2): 272-280, Mar.-Apr. 2009. mapas, graf, tab
Artigo em Inglês | LILACS | ID: lil-515110

RESUMO

Autochthonous malaria cases in the state of Espírito Santo, Brazil, are distributed in mountainous regions surrounded by the Atlantic Forest. While some aspects of this disease are unclear, detection of possible vector species can help to elucidate epidemiological uncertainties. Entomological and natural infection studies were carried out using anophelines (Diptera: Culicidae) captured in the municipality of Santa Tereza, ES. Monthly captures were made from March 2004 to February 2006. CDC-CO2 traps were used from dusk (6:00 P.M.) to dawn (6:00 A.M.) to capture anophelines in the following habitats: near the houses, in open areas (at ground level) and inside, and at the margins of the forest (canopy and ground level). Shannon light traps were also used at the same locations of the CDC-CO2 traps. A total of 2,290 anophelines within 10 species were captured. The relative frequency of Anopheles (Kerteszia) cruzii Dyar & Knab / A. (K.) homunculus Komp was the highest, with the majority captured in CDC-CO2 traps installed in the forest canopy. The main species captured in Shannon traps was A. (Nyssorhynchus) strodei Root. The largest number of anophelines was captured from July to September and from 6:00 P.M. to 10:00 P.M. Anopheles (K.) cruzii is the probable vector for malaria transmission inside or near the Atlantic Forest fragments, but the role of other species cannot be ignored, as 53 percent of the sampled anophelines belonged to the subgenus Nyssorhynchus. The natural infection of A. cruzii, A. parvus (Chagas) and A. galvaoi Causey, Deane & Deane by Plasmodium vivax detected by PCR from DNA extracted from their thoraxes supports this view.


No Espírito Santo, os casos de malária autóctone estão distribuídos na região serrana próximo aos fragmentos de Mata Atlântica. Uma vez que alguns aspectos da doença são obscuros, a detecção das possíveis espécies de vetores pode auxiliar na elucidação de incertezas epidemiológicas. Estudos entomológicos e de infecção natural foram realizados com anofelinos (Diptera: Culicidae) capturados no município de Santa Tereza, ES. Capturas mensais foram realizadas de março de 2004 a fevereiro de 2006. Armadilhas CDC-CO2 foram utilizadas do crepúsculo (18:00h) ao amanhecer (6:00h), para capturar anofelinos nos seguintes habitats: próximo ao domicílio e área aberta (solo), margem e interior da mata (solo e copa). Armadilhas Shannon também foram utilizadas nos mesmos locais que as de CDC-CO2. Capturou-se o total de 2.290 anofelinos distribuídos em 10 espécies. A maior frequência relativa foi de Anopheles (Kerteszia) cruzii Dyar & Knab / A. (K.) homunculus Komp, sendo a maioria capturada em CDC-CO2 instalada na copa da mata. A principal espécie capturada em armadilha Shannon foi A.(Nyssorhynchus) strodei Root. O maior número de anofelinos foi capturado entre julho e setembro das 18:00h às 22:00h. Provavelmente A. (K.) cruzii é responsável pela transmissão da malária dentro ou próximo aos fragmentos de Mata Atlântica. Entretanto, a participação de outras espécies não pode ser ignorada, visto que 53 por cento da amostragem foi constituída pelo subgênero Nyssorhynchus. A detecção de Plasmodium vivax no tórax de A. cruzii, A. parvus (Chagas) e A. galvaoi Causey, Deane & Deane por meio de PCR reforça esse argumento.


Assuntos
Animais , Anopheles/parasitologia , Plasmodium vivax/isolamento & purificação , Brasil , Árvores
7.
São Paulo; s.n; 2010. [262] p. mapas, ilus, tab, graf.
Tese em Português | LILACS | ID: lil-575198

RESUMO

A Mata Atlântica não possui fisionomia uniforme, pois seu relevo determina diferentes condições ambientais que definem a composição de sua fauna e flora. Em uma mesma região, a diversidade de espécies pode variar de acordo com a heterogeneidade dos habitats. Objetivo: Caracterizar a fauna de Culicidae em fitotelmatas de bromélias (Bromeliaceae), no município de Cananéia, São Paulo, Brasil. Métodos: Larvas e pupas de culicídeos foram obtidas, mensalmente, do conteúdo aquático de bromélias de três ambientes: planície, encosta e morro. As coletas ocorreram entre julho de 2008 e junho de 2009. Para estimar a variedade de espécies foram utilizados os índices de Margalef e de Menhinick. O índice de Jaccard e o de Sorensen indicaram a semelhança entre bromélias de dois ambientes. Para avaliar a dominância, empregou-se o índice de Simpson e de Berger-Parker. A equidade na distribuição das espécies foi avaliada pelo índice de Pielou e a constância em cada ambiente pelo índice c. Os testes estatísticos empregados foram: análise de variância (ANOVA) com o teste de Fisher; teste Kruskal-Wallis e valor p; teste de associação qui-quadrado e regressão linear simples por meio do coeficiente de correlação de Pearson. Resultados: O teste Kruskal-Wallis mostrou diferenças significantes para o volume hídrico das bromélias de cada ambiente (p=0,002, IC= 95 por cento) mas não para o valor do pH (p= 0,775). Foram identificados 2024 mosquitos, 786 (38,83 por cento) na planície, 606 (29,94 por cento) na encosta e 632 (31,23 por cento) no morro, dentre eles: Culex (Microculex) (62,25 por cento), Culex ocellatus (21,20 por cento), Anopheles (Kerteszia) (15,17 por cento), Wyemoyia (Phoniomyia) (1,33 por cento) e Runchomyia (Runchomyia) (0,05 por cento). O índice de riqueza de Margalef foi maior na planície (d1=2,55) e menor no morro (d1=1,86), e o de Sorensen indicou encosta e morro como os ambientes mais similares (QS=0,79) e planície e morro como os menos similares (QS=0,65)...


Atlantic Forest is not uniform and its relief determines different environmental conditions that define the composition of its fauna and flora. Thus, in the same region, species diversity may vary according to habitat heterogeneity. Objective: To assess mosquito (Culicidae) fauna in bromeliads phytotelmate (Bromeliaceae), in Cananéia, São Paulo, Brazil. Methods: The larvae and pupae of mosquitoes were collected monthly in the water content of bromeliads from three regions: the lowland, hillside and hilltop. Sampling occurred between July 2008 and June 2009. To estimate richness, Margalef and Menhinick indices were used. Jaccard and Sorensen indices indicated the similarity between bromeliads from two regions. To assess dominance, we employed Simpson and Berger-Parker índices. Equity in the distribution of species was assessed by Pielou index and c index evaluated species constancy in each region. Statistical analyses applied were: ANOVA with Fisher's exact test, Kruskal-Wallis test and p value; Chi-square association test and linear regression using Pearson correlation coefficient. Results: Kruskal-Wallis test showed significant differences in water volume for bromeliads from each region (p=0,002, CI=95 per cent) but not for the pH value (p=0,775). In all, 2024 mosquitoes were identified, 786 (38,83 per cent) in the lowland, 606 (29,94 per cent) on the hillside and 632 (31,23 per cent) on the hilltop, among them: Culex (Microculex) (62,25 per cent), Culex ocellatus (21,20 per cent), Anopheles (Kerteszia) (15,17 per cent), Wyemoyia (Phoniomyia) (1,33 per cent) and Runchomyia (Runchomyia) (0,05 per cent). Margalef richness index was higher in the lowland (d1=2,55) and lower on the hilltop (d1=1,86). According to the Sorensen similarity index, species from the hillside are more likely to be found on the hilltop (QS=0,79) than in the lowland (QS=0,73). The greatest differences occurred between the hilltop and the lowland (QS=0,65). The 2 test showed...


Assuntos
Anopheles , Biodiversidade , Bromeliaceae , Culicidae , Fauna , Controle Biológico de Vetores
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