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1.
Malar J ; 23(1): 166, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807105

RESUMO

BACKGROUND: Deforestation is an important driver of malaria dynamics, with a relevant impact on mosquito ecology, including larval habitat availability, blood-feeding behaviour, and peak biting time. The latter is one of several entomological metrics to evaluate vectorial capacity and effectiveness of disease control. This study aimed to test the effect of forest cover percentage on the peak biting time of Plasmodium-uninfected and infected Nyssorhynchus darlingi females. METHODS: Mosquitoes were captured utilizing human landing catch (HLC) in the peridomestic habitat in field collections carried out in the wet, wet-dry transition, and dry seasons from 2014 to 2017 in areas with active malaria transmission in Amazonian Brazil. The study locations were in rural settlements in areas with the mean annual malaria parasite incidence (Annual Parasite Incidence, API ≥ 30). All Ny. darlingi females were tested for Plasmodium spp. infection using real time PCR technique. Forest cover percentage was calculated for each collection site using QGIS v. 2.8 and was categorized in three distinct deforestation scenarios: (1) degraded, < 30% forest cover, (2) intermediate, 30-70% forest cover, and (3) preserved, > 70% forest cover. RESULTS: The highest number of uninfected female Ny. darlingi was found in degraded landscape-sites with forest cover < 30% in any peak biting time between 18:00 and 0:00. Partially degraded landscape-sites, with (30-70%) forest cover, showed the highest number of vivax-infected females, with a peak biting time of 21:00-23:00. The number of P. falciparum-infected mosquitoes was highest in preserved sites with > 70% forest cover, a peak biting at 19:00-20:00, and in sites with 30-70% forest cover at 22:00-23:00. CONCLUSIONS: Results of this study show empirically that degraded landscapes favour uninfected Ny. darlingi with a peak biting time at dusk (18:00-19:00), whereas partially degraded landscapes affect the behaviour of Plasmodium-infected Ny. darlingi by shifting its peak biting time towards hours after dark (21:00-23:00). In preserved sites, Plasmodium-infected Ny. darlingi bite around dusk (18:00-19:00) and shortly after (19:00-20:00).


Assuntos
Comportamento Alimentar , Florestas , Mosquitos Vetores , Animais , Brasil , Feminino , Mosquitos Vetores/fisiologia , Mosquitos Vetores/parasitologia , Conservação dos Recursos Naturais , Mordeduras e Picadas de Insetos/epidemiologia , Estações do Ano , Malária/transmissão
2.
Mem Inst Oswaldo Cruz ; 113(9): e170522, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30043836

RESUMO

The Malaria Frontier Hypothesis (MFH) is the current model for predicting malaria emergence in the Brazilian Amazon. It has two important dimensions, 'settlement time' and 'malaria incidence', and its prediction are: malaria incidence peaks five years after the initiation of human settlement and declines towards zero after an estimated 10 years. Although MFH is currently accepted, it has been challenged recently. Herein, we described a novel method for estimating settlement timeline by using remote sensing technology integrated in an open-software geographic information system. Surprisingly, we found that of the majority of the rural settlements with high malaria incidence are more than 10 years old.


Assuntos
Conservação dos Recursos Naturais , Florestas , Malária/transmissão , Brasil/epidemiologia , Conservação dos Recursos Naturais/tendências , Sistemas de Informação Geográfica , Humanos , Incidência , Malária/epidemiologia , Malária/parasitologia , Carga Parasitária , População Rural , Fatores de Tempo
3.
Insects ; 13(2)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35206775

RESUMO

Hand-held insect nets are the standard method for capturing vector mosquitoes of sylvatic arboviruses; however, occupational risks and biases due to individual skill and attractiveness are important limitations. The use of chemical attractants and automatic traps could be an alternative to resolve these limitations. This study compares the yields achieved using nets with those employing electrical traps with CO2 and BG-Lure®, near the ground and in the canopy strata (6.0 and 8.0 m high). The study was conducted at the Cantareira State Park, which is in the Brazilian Atlantic Forest biome. In the 18 collections performed, 3570 specimens of 52 taxa were obtained. The most frequent species captured near the ground were Wyeomyia confusa and Limatus durhamii, whereas Sabethes albiprivus, Sabethes purpureus, and Haemagogus leucocelaenus were the most frequent in the canopy. The nets resulted in greater species richness and abundance, followed by the trap employing CO2. The combination of CO2 traps with BG-Lure® did not improve performance. The use of BG-Lure® alone resulted in low abundance and a low number of species. Our results demonstrate that the use of traps with CO2 can be complementary to collections with nets; however, for species of epidemiological interest such as those of the genera Haemagogus and Sabethes, especially in the canopy, the net remains the method of choice.

4.
Mem Inst Oswaldo Cruz ; 106(6): 705-15, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22012225

RESUMO

Phylogenetic relationships among species of the Myzorhynchella Section of Anopheles (Nyssorhynchus) were investigated using the nuclear ribosomal DNA second internal transcribed spacer (ITS2), the nuclear whitegene and mitochondrial cytochrome oxidase subunit I (COI) regions. The recently described Anopheles pristinus and resurrected Anopheles guarani were also included in the study. Bayesian phylogenetic analyses found Anopheles parvus to be the most distantly related species within the Section, a finding that is consistent with morphology. An. pristinus and An. guarani were clearly resolved from Anopheles antunesi and Anopheles lutzii, respectively. An. lutzii collected in the same mountain range as the type locality were found within a strongly supported clade, whereas individuals from the southern state of Rio Grande do Sul, tentatively identified as An. lutzii based on adult female external morphology, were distinct from An. lutzii, An. antunesi and from each other, and may therefore represent two new sympatric species. A more detailed examination of An. lutzii sensu latoalong its known geographic range is recommended to resolve these anomalous relationships.


Assuntos
Anopheles/genética , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Insetos/genética , Animais , Anopheles/classificação , Teorema de Bayes , Núcleo Celular/genética , Feminino , Mitocôndrias/enzimologia , Filogenia , Especificidade da Espécie
5.
J Am Mosq Control Assoc ; 27(3): 191-200, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22017082

RESUMO

We analyzed nuclear (second internal transcribed spacer and white gene) and mitochondrial (cytochrome c oxidase subunit I) data from Anopheles konderi collected in the Amazonian states of Acre, Amapá, and Rondônia and the southern Brazilian state of Paraná. This was the first record of An. konderi in the state of Paraná. We found a high degree of genetic divergence within the Amazonian region and support for An. konderi as a species complex, possibly consisting of 3 species.


Assuntos
Anopheles/genética , Animais , Anopheles/classificação , Brasil , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Masculino , Filogenia
6.
PLoS One ; 16(1): e0245087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33444320

RESUMO

Inter-relationships among mosquito vectors, Plasmodium parasites, human ecology, and biotic and abiotic factors, drive malaria risk. Specifically, rural landscapes shaped by human activities have a great potential to increase the abundance of malaria vectors, putting many vulnerable people at risk. Understanding at which point the abundance of vectors increases in the landscape can help to design policies and interventions for effective and sustainable control. Using a dataset of adult female mosquitoes collected at 79 sites in malaria endemic areas in the Brazilian Amazon, this study aimed to (1) verify the association among forest cover percentage (PLAND), forest edge density (ED), and variation in mosquito diversity; and to (2) test the hypothesis of an association between landscape structure (i.e., PLAND and ED) and Nyssorhynchus darlingi (Root) dominance. Mosquito collections were performed employing human landing catch (HLC) (peridomestic habitat) and Shannon trap combined with HLC (forest fringe habitat). Nyssorhynchus darlingi abundance was used as the response variable in a generalized linear mixed model, and the Shannon diversity index (H') of the Culicidae community, PLAND, and the distance house-water drainage were used as predictors. Three ED categories were also used as random effects. A path analysis was used to understand comparative strengths of direct and indirect relationships among Amazon vegetation classes, Culicidae community, and Ny. darlingi abundance. Our results demonstrate that Ny. darlingi is negatively affected by H´ and PLAND of peridomestic habitat, and that increasing these variables (one-unit value at ß0 = 768) leads to a decrease of 226 (P < 0.001) and 533 (P = 0.003) individuals, respectively. At the forest fringe, a similar result was found for H' (ß1 = -218; P < 0.001) and PLAND (ß1 = -337; P = 0.04). Anthropogenic changes in the Amazon vegetation classes decreased mosquito biodiversity, leading to increased Ny. darlingi abundance. Changes in landscape structure, specifically decreases in PLAND and increases in ED, led to Ny. darlingi becoming the dominant species, increasing malaria risk. Ecological mechanisms involving changes in landscape and mosquito species composition can help to understand changes in the epidemiology of malaria.


Assuntos
Biodiversidade , Culicidae/crescimento & desenvolvimento , Atividades Humanas , Insetos Vetores/crescimento & desenvolvimento , Malária/parasitologia , Floresta Úmida , Animais , Brasil , Geografia , Modelos Lineares , Modelos Teóricos , Análise de Componente Principal
7.
Travel Med Infect Dis ; 37: 101792, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32771653

RESUMO

BACKGROUND: Human mobility between malaria endemic and malaria-free areas can hinder control and elimination efforts in the Amazon basin, maintaining Plasmodium circulation and introduction to new areas. METHODS: The analysis begins by estimating the incidence of malaria in areas of interest. Then, the risk of infection as a function of the duration of stay after t0 was calculated as the number of infected travelers over the number of arrived travelers. Differential equations were employed to estimate the risk of nonimmune travelers acquiring malaria in Amazonian municipalities. Risk was calculated as a result of the force of the infection in terms of local dynamics per time of arrival and duration of visit. RESULTS: Maximum risk occurred at the peak or at the end of the rainy season and it was nonlinearly (exponentially) correlated with the fraction of infected mosquitoes. Relationship between the risk of malaria and duration of visit was linear and positively correlated. Relationship between the risk of malaria and the time of arrival in the municipality was dependent on local effects of seasonality. CONCLUSIONS: The risk of nonimmune travelers acquiring malaria is not negligible and can maintain regional circulation of parasites, propagating introductions in areas where malaria has been eliminated.


Assuntos
Malária , Plasmodium , Doença Relacionada a Viagens , Animais , Brasil/epidemiologia , Cidades , Humanos , Incidência
8.
Acta Trop ; 164: 137-149, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27609637

RESUMO

The subgenus Melanoconion is the second largest subgenus within the genus Culex, with 160 described species. Several of the species are proven vectors of arboviruses, including West Nile virus, Venezuelan equine encephalitis virus complex and Eastern equine encephalomyelitis virus. Species of Melanoconion are well distributed from southern North America to most countries of South America and display the highest species diversity in tropical regions. Taxonomical identification within this group has been primarily based on morphological characters, with the male genitalia as the source of the most solid diagnostic features. The difficulty in reaching accurate species determinations when studying specimens of Culex (Melanoconion) has been extensively documented as a real limitation to expand knowledge of these insects. We tested the utility of the mitochondrial gene COI as a complementary tool in the taxonomy of Melanoconion. Using a data set of 120 COI sequences from Culex specimen captured in several localities in Brazil, the utility of COI barcodes for species delimitation is discussed through the evaluation of genetic divergences among specimens and the clustering patterns of species in three topologies obtained with Neighbor Joining, Maximum Likelihood and Bayesian phylogenetic inference. For all specimens included in this study a previous morphological examination was performed, and most of the taxonomical determinations were corroborated using the COI barcode. We generated COI sequences that belong to 48 species of Melanoconion, with a mean intraspecific K2P genetic divergence of 3%; and all interspecific divergence values higher than the intraspecific divergence values. This is the first comprehensive study of subgenus Melanoconion, with evidence of COI as a useful and accessible DNA barcode.


Assuntos
Culex/genética , Ciclo-Oxigenase 1/genética , Proteínas de Insetos/análise , Insetos Vetores/genética , Mitocôndrias/genética , Animais , Teorema de Bayes , Brasil , Análise por Conglomerados , Culex/classificação , Código de Barras de DNA Taxonômico , Insetos Vetores/classificação , Filogenia
9.
Parasit Vectors ; 8: 426, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26283539

RESUMO

BACKGROUND: Malaria remains a significant public health issue in South America. Future climate change may influence the distribution of the disease, which is dependent on the distribution of those Anopheles mosquitoes competent to transmit Plasmodium falciparum. Herein, predictive niche models of the habitat suitability for P. falciparum, the current primary vector Anopheles darlingi and nine other known and/or potential vector species of the Neotropical Albitarsis Complex, were used to document the current situation and project future scenarios under climate changes in South America in 2070. METHODS: To build each ecological niche model, we employed topography, climate and biome, and the currently defined distribution of P. falciparum, An. darlingi and nine species comprising the Albitarsis Complex in South America. Current and future (i.e., 2070) distributions were forecast by projecting the fitted ecological niche model onto the current environmental situation and two scenarios of simulated climate change. Statistical analyses were performed between the parasite and each vector in both the present and future scenarios to address potential vector roles in the dynamics of malaria transmission. RESULTS: Current distributions of malaria vector species were associated with that of P. falciparum, confirming their role in transmission, especially An. darlingi, An. marajoara and An. deaneorum. Projected climate changes included higher temperatures, lower water availability and biome modifications. Regardless of future scenarios considered, the geographic distribution of P. falciparum was exacerbated in 2070 South America, with the distribution of the pathogen covering 35-46% of the continent. As the current primary vector An. darlingi showed low tolerance for drier environments, the projected climate change would significantly reduce suitable habitat, impacting both its distribution and abundance. Conversely, climate generalist members of the Albitarsis Complex showed significant spatial and temporal expansion potential in 2070, and we conclude these species will become more important in the dynamics of malaria transmission in South America. CONCLUSIONS: Our data suggest that climate and landscape effects will elevate the importance of members of the Albitarsis Complex in malaria transmission in South America in 2070, highlighting the need for further studies addressing the bionomics, ecology and behaviours of the species comprising the Albitarsis Complex.


Assuntos
Anopheles/crescimento & desenvolvimento , Insetos Vetores/crescimento & desenvolvimento , Animais , Anopheles/parasitologia , Mudança Climática , Entomologia , Insetos Vetores/parasitologia , Malária Falciparum/transmissão , Modelos Estatísticos , Filogeografia , Plasmodium falciparum/isolamento & purificação , América do Sul/epidemiologia
10.
Rev Inst Med Trop Sao Paulo ; 46(4): 223-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15361975

RESUMO

Diversity of mosquito species was evaluated in different habitats before and after the Igarapava reservoir flooding in the Grande River, Southern Cerrado of Brazil. We aimed at verifying changes in these mosquito populations in consequence of the lake formation. Four habitats were selected as sampling stations: peridomiciliary habitat, pasture, "veredas" and gallery forest patch. Bimonthly collections were made with the Shannon trap and human bait, including diurnal, crepuscular and nocturnal period of mosquito activity. The Shannon Index results from the potential vectors were compared using Student t-test. Aedes scapularis, Anopheles darlingi and An. albitarsis senso latu seasonal abundance were described with moving average and compared using chi2 test. There were changes in the mosquito frequency in the habitats, except for the "veredas" that was 13 km away from the catchment area. The altering in mosquito species seasonal abundance suggests breeding places expansion. Diversity indexes can be used to monitor changes in mosquito vector population in environments where abrupt disturbance can alter disease transmission cycles.


Assuntos
Aedes/classificação , Anopheles/classificação , Biodiversidade , Insetos Vetores/classificação , Aedes/fisiologia , Animais , Anopheles/fisiologia , Brasil , Humanos , Insetos Vetores/fisiologia , Malária/transmissão , Densidade Demográfica , Estações do Ano
11.
J Am Mosq Control Assoc ; 18(1): 10-5, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11998924

RESUMO

The ultrastructure of the eggs of Anopheles (Nyssorhynchus) galvaoi Causey, Deane, and Deane and Anopheles (Nyssorhynchus) evansae (Brethes) are described and illustrated with scanning electron micrographs. The eggs of these species are similar to those of Anopheles (Nyssorhynchus) aquasalis Curry, Anopheles (Nyssorhynchus) oswaldoi (Peryassu), and Anopheles (Nyssorhynchus) konderi Galvão and Damasceno in having floats long, widely joined posteriorly on the dorsal surface, the frill encircling the anterior end of the egg, and the crown absent. A few distinctive characters to distinguish An. evansae from An. galvaoi are given.


Assuntos
Anopheles/ultraestrutura , Óvulo/ultraestrutura , Animais , Feminino , Microscopia Eletrônica de Varredura
12.
Parasit Vectors ; 6: 111, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23597081

RESUMO

BACKGROUND: The ability to successfully identify and incriminate pathogen vectors is fundamental to effective pathogen control and management. This task is confounded by the existence of cryptic species complexes. Molecular markers can offer a highly effective means of species identification in such complexes and are routinely employed in the study of medical entomology. Here we evaluate a multi-locus system for the identification of potential malaria vectors in the Anopheles strodei subgroup. METHODS: Larvae, pupae and adult mosquitoes (n = 61) from the An. strodei subgroup were collected from 21 localities in nine Brazilian states and sequenced for the COI, ITS2 and white gene. A Bayesian phylogenetic approach was used to describe the relationships in the Strodei Subgroup and the utility of COI and ITS2 barcodes was assessed using the neighbor joining tree and "best close match" approaches. RESULTS: Bayesian phylogenetic analysis of the COI, ITS2 and white gene found support for seven clades in the An. strodei subgroup. The COI and ITS2 barcodes were individually unsuccessful at resolving and identifying some species in the Subgroup. The COI barcode failed to resolve An. albertoi and An. strodei but successfully identified approximately 92% of all species queries, while the ITS2 barcode failed to resolve An. arthuri and successfully identified approximately 60% of all species queries. A multi-locus COI-ITS2 barcode, however, resolved all species in a neighbor joining tree and successfully identified all species queries using the "best close match" approach. CONCLUSIONS: Our study corroborates the existence of An. albertoi, An. CP Form and An. strodei in the An. strodei subgroup and identifies four species under An. arthuri informally named A-D herein. The use of a multi-locus barcode is proposed for species identification, which has potentially important utility for vector incrimination. Individuals previously found naturally infected with Plasmodium vivax in the southern Amazon basin and reported as An. strodei are likely to have been from An. arthuri C identified in this study.


Assuntos
Anopheles/classificação , Anopheles/genética , Código de Barras de DNA Taxonômico/métodos , Entomologia/métodos , Tipagem de Sequências Multilocus , Animais , Brasil , Análise por Conglomerados , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
13.
Mem. Inst. Oswaldo Cruz ; 113(9): e170522, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-955127

RESUMO

The Malaria Frontier Hypothesis (MFH) is the current model for predicting malaria emergence in the Brazilian Amazon. It has two important dimensions, 'settlement time' and 'malaria incidence', and its prediction are: malaria incidence peaks five years after the initiation of human settlement and declines towards zero after an estimated 10 years. Although MFH is currently accepted, it has been challenged recently. Herein, we described a novel method for estimating settlement timeline by using remote sensing technology integrated in an open-software geographic information system. Surprisingly, we found that of the majority of the rural settlements with high malaria incidence are more than 10 years old.


Assuntos
Humanos , Sistemas de Informação Geográfica/organização & administração , Malária/parasitologia , Malária/transmissão , Malária/epidemiologia , População Rural , Brasil/epidemiologia , Florestas , Conservação dos Recursos Naturais/tendências , Carga Parasitária/estatística & dados numéricos
14.
Infect Genet Evol ; 12(6): 1246-52, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22522004

RESUMO

We undertook geometric morphometric analysis of wing venation to assess this character's ability to distinguish Anopheles darlingi Root populations and to test the hypothesis that populations from coastal areas of the Brazilian Atlantic Forest differ from those of the interior Atlantic Forest, Cerrado, and the regions South and North of the Amazon River. Results suggest that populations from the coastal and interior Atlantic Forest are more similar to each other than to any of the other regional populations. Notably, the Cerrado population was more similar to that from north of the Amazon River than to that collected of south of the River, thus showing no correlation with geographical distances. We hypothesize that environmental and ecological factors may affect wing evolution in An. darlingi. Although it is premature to associate environmental and ecological determinants with wing features and evolution of the species, investigations on this field are promising.


Assuntos
Anopheles/anatomia & histologia , Insetos Vetores/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Brasil , Ecossistema , Feminino , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes
15.
Rev Soc Bras Med Trop ; 44(3): 290-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21739073

RESUMO

INTRODUCTION: Following yellow fever virus (YFV) isolation in monkeys from the São José do Rio Preto region and two fatal human autochthonous cases from the Ribeirão Preto region, State of São Paulo, Brazil, two expeditions for entomological research and eco-epidemiological evaluation were conducted. METHODS: A total of 577 samples from humans, 108 from monkeys and 3,049 mosquitoes were analyzed by one or more methods: virus isolation, ELISA-IgM, RT-PCR, histopathology and immunohistochemical. RESULTS: Of the 577 human samples, 531 were tested by ELISA-IgM, with 3 positives, and 235 were inoculated into mice and 199 in cell culture, resulting in one virus isolation. One sample was positive by histopathology and immunohistochemical. Using RT-PCR, 25 samples were processed with 4 positive reactions. A total of 108 specimens of monkeys were examined, 108 were inoculated into mice and 45 in cell culture. Four virus strains were isolated from Alouatta caraya. A total of 931 mosquitoes were captured in Sao Jose do Rio Preto and 2,118 in Ribeirão Preto and separated into batches. A single isolation of YFV was derived from a batch of 9 mosquitoes Psorophora ferox, collected in Urupês, Ribeirão Preto region. A serological survey was conducted with 128 samples from the municipalities of São Carlos, Rincão and Ribeirão Preto and 10 samples from contacts of patients from Ribeirão Preto. All samples were negative by ELISA-IgM for YFV. CONCLUSIONS: The results confirm the circulation of yellow fever, even though sporadic, in the Sao Paulo State and reinforce the importance of vaccination against yellow fever in areas considered at risk.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Culicidae/classificação , Haplorrinos/virologia , Insetos Vetores/classificação , Doenças dos Macacos/epidemiologia , Febre Amarela/epidemiologia , Animais , Brasil/epidemiologia , Doenças Transmissíveis Emergentes/diagnóstico , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/veterinária , Haplorrinos/classificação , Humanos , Doenças dos Macacos/diagnóstico , Doenças dos Macacos/transmissão , Estudos Soroepidemiológicos , Febre Amarela/diagnóstico , Febre Amarela/transmissão , Febre Amarela/veterinária
16.
Rev Inst Med Trop Sao Paulo ; 53(3): 133-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21755235

RESUMO

After detecting the death of Howlers monkeys (genus Alouatta) and isolation of yellow fever virus (YFV) in Buri county, São Paulo, Brazil, an entomological research study in the field was started. A YFV strain was isolated from newborn Swiss mice and cultured cells of Aedes albopictus - C6/36, from a pool of six Haemagogus (Conopostegus) leucocelaenus (Hg. leucocelaenus) mosquitoes (Dyar & Shannon) collected at the study site. Virus RNA fragment was amplified by RT-PCR and sequenced. The MCC Tree generated showed that the isolated strain is related to the South American I genotype, in a monophyletic clade containing isolates from recent 2008-2010 epidemics and epizootics in Brazil. Statistical analysis commonly used were calculated to characterize the sample in relation to diversity and dominance and indicated a pattern of dominance of one or a few species. Hg. leucocelaenus was found infected in Rio Grande do Sul State as well. In São Paulo State, this is the first detection of YFV in Hg. leucocelaenus.


Assuntos
Culicidae/virologia , Insetos Vetores/virologia , RNA Viral/análise , Vírus da Febre Amarela/isolamento & purificação , Alouatta , Animais , Brasil , Culicidae/classificação , Insetos Vetores/classificação , Camundongos , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Febre Amarela/transmissão , Vírus da Febre Amarela/genética
17.
Mem. Inst. Oswaldo Cruz ; 106(6): 705-715, Sept. 2011. ilus, tab
Artigo em Inglês | LILACS, SES-SP | ID: lil-602054

RESUMO

Phylogenetic relationships among species of the Myzorhynchella Section of Anopheles (Nyssorhynchus) were investigated using the nuclear ribosomal DNA second internal transcribed spacer (ITS2), the nuclear whitegene and mitochondrial cytochrome oxidase subunit I (COI) regions. The recently described Anopheles pristinus and resurrected Anopheles guarani were also included in the study. Bayesian phylogenetic analyses found Anopheles parvus to be the most distantly related species within the Section, a finding that is consistent with morphology. An. pristinus and An. guarani were clearly resolved from Anopheles antunesi and Anopheles lutzii, respectively. An. lutzii collected in the same mountain range as the type locality were found within a strongly supported clade, whereas individuals from the southern state of Rio Grande do Sul, tentatively identified as An. lutzii based on adult female external morphology, were distinct from An. lutzii, An. antunesi and from each other, and may therefore represent two new sympatric species. A more detailed examination of An. lutzii sensu latoalong its known geographic range is recommended to resolve these anomalous relationships.


Assuntos
Animais , Feminino , Anopheles/genética , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Insetos/genética , Anopheles/classificação , Teorema de Bayes , Núcleo Celular/genética , Mitocôndrias/enzimologia , Filogenia , Especificidade da Espécie
18.
Rev. Soc. Bras. Med. Trop ; 44(3): 290-296, May-June 2011. ilus, tab
Artigo em Inglês | LILACS, SES-SP | ID: lil-593362

RESUMO

INTRODUCTION: Following yellow fever virus (YFV) isolation in monkeys from the São José do Rio Preto region and two fatal human autochthonous cases from the Ribeirão Preto region, State of São Paulo, Brazil, two expeditions for entomological research and eco-epidemiological evaluation were conducted. METHODS: A total of 577 samples from humans, 108 from monkeys and 3,049 mosquitoes were analyzed by one or more methods: virus isolation, ELISA-IgM, RT-PCR, histopathology and immunohistochemical. RESULTS: Of the 577 human samples, 531 were tested by ELISA-IgM, with 3 positives, and 235 were inoculated into mice and 199 in cell culture, resulting in one virus isolation. One sample was positive by histopathology and immunohistochemical. Using RT-PCR, 25 samples were processed with 4 positive reactions. A total of 108 specimens of monkeys were examined, 108 were inoculated into mice and 45 in cell culture. Four virus strains were isolated from Alouattacaraya. A total of 931 mosquitoes were captured in Sao Jose do Rio Preto and 2,118 in Ribeirão Preto and separated into batches. A single isolation of YFV was derived from a batch of 9 mosquitoes Psorophoraferox, collected in Urupês, Ribeirão Preto region. A serological survey was conducted with 128 samples from the municipalities of São Carlos, Rincão and Ribeirão Preto and 10 samples from contacts of patients from Ribeirão Preto. All samples were negative by ELISA-IgM for YFV. CONCLUSIONS: The results confirm the circulation of yellow fever, even though sporadic, in the Sao Paulo State and reinforce the importance of vaccination against yellow fever in areas considered at risk.


INTRODUÇÃO: A partir do isolamento do vírus febre amarela (VFA), de macacos, da região de São José do Rio Preto e de dois casos humanos autóctones fatais, da região de Ribeirão Preto, Estado de São Paulo, foram realizadas duas expedições para pesquisa entomológica e avaliação ecoepidemiológica. MÉTODOS: Um total de 577 amostras de humanos, 108 de macacos e 3.049 mosquitos foram analisados por um ou mais métodos: isolamento viral, ELISA-IgM, RT-PCR, histopatologia e imunohistoquímica. RESULTADOS: De 577 amostras humanas, 531 foram testadas por ELISA-IgM, sendo 3 positivas, 235 foram inoculadas em camundongos, 199 em cultura de células, obtendo-se 1 isolamento viral. Uma amostra foi positiva por histopatologia e imunohistoquímica. Por RT-PCR foram processadas 25 amostras com 4 reações positivas. Os 108 espécimes de macacos foram inoculados em camundongos, 45 em cultura de células, obtendo-se 4 isolamentos de VFA, de Alouatta caraya. Um total de 931 mosquitos foram capturados em São José do Rio Preto e 2.118 em Ribeirão Preto e separados em lotes. Um único isolamento de VFA foi derivado de um lote de 9 mosquitos Psorophora ferox, coletados em Urupês, região de Ribeirão Preto. Um inquérito sorológico foi realizado com 128 amostras dos municípios de São Carlos, Rincão e Ribeirão Preto e mais 10 amostras de contactantes de pacientes de Ribeirão Preto. Todas as amostras foram negativas por ELISA-IgM para VFA. CONCLUSÕES: Os resultados confirmam a circulação, mesmo que esporádica, do VFA no Estado de São Paulo e reforça a importância da vacinação antiamarílica nas áreas consideradas de risco.


Assuntos
Animais , Humanos , Doenças Transmissíveis Emergentes/epidemiologia , Culicidae/classificação , Haplorrinos/virologia , Insetos Vetores/classificação , Doenças dos Macacos/epidemiologia , Febre Amarela/epidemiologia , Brasil/epidemiologia , Doenças Transmissíveis Emergentes/diagnóstico , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/veterinária , Haplorrinos/classificação , Doenças dos Macacos/diagnóstico , Doenças dos Macacos/transmissão , Estudos Soroepidemiológicos , Febre Amarela/diagnóstico , Febre Amarela/transmissão , Febre Amarela/veterinária
19.
Rev. Inst. Med. Trop. Säo Paulo ; 53(3): 133-139, May-June 2011. ilus, mapas, tab
Artigo em Inglês | LILACS, SES-SP | ID: lil-592773

RESUMO

After detecting the death of Howlers monkeys (genus Alouatta) and isolation of yellow fever virus (YFV) in Buri county, São Paulo, Brazil, an entomological research study in the field was started. A YFV strain was isolated from newborn Swiss mice and cultured cells of Aedes albopictus - C6/36, from a pool of six Haemagogus (Conopostegus) leucocelaenus (Hg. leucocelaenus) mosquitoes (Dyar & Shannon) collected at the study site. Virus RNA fragment was amplified by RT-PCR and sequenced. The MCC Tree generated showed that the isolated strain is related to the South American I genotype, in a monophyletic clade containing isolates from recent 2008-2010 epidemics and epizootics in Brazil. Statistical analysis commonly used were calculated to characterize the sample in relation to diversity and dominance and indicated a pattern of dominance of one or a few species. Hg. leucocelaenus was found infected in Rio Grande do Sul State as well. In São Paulo State, this is the first detection of YFV in Hg. leucocelaenus.


Após a detecção de morte de macacos Bugios (gênero Alouatta) e isolamento do vírus da Febre Amarela (YFV) no município de Buri, Estado de São Paulo, Brasil, foi iniciada uma investigação entomológica em campo. Uma cepa de YFV foi isolada em camundongos recém-nascidos e cultura de células de Aedes albopictus - C6/36, a partir de um lote de seis mosquitos Haemagogus (Conopostegus) leucocelaenus (Hg leucocelaenus) Dyar & Shannon coletados no local de estudo. RNA do vírus foi amplificado por RT-PCR e seqüenciado. A topologia gerada indica que a cepa isolada está relacionada ao genótipo South American I, em clado monofilético englobando isolados recentes de epidemias e epizootias entre 2008 e 2009. Análises estatísticas geralmente usadas caracterizaram a amostra em relação à diversidade e dominância, indicando dominância relativa de uma ou poucas espécies. Hg. leucocelaenus foi detectado infectado também no Rio Grande do Sul. No Estado de São Paulo trata-se da primeira detecção do YFV em Hg leucocelaenus.


Assuntos
Animais , Camundongos , Culicidae/virologia , Insetos Vetores/virologia , RNA Viral/análise , Vírus da Febre Amarela/isolamento & purificação , Alouatta , Brasil , Culicidae/classificação , Insetos Vetores/classificação , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Febre Amarela/transmissão , Vírus da Febre Amarela/genética
20.
Mem Inst Oswaldo Cruz ; 97(8): 1177-89, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12563487

RESUMO

Anopheles galvaoi, a member of the subgenus Nyssorhynchus, is redescribed based on morphological characters of the adults male and female, fourth-instar larva and pupa. Female, male genitalia, larval and pupal stages are illustrated. Data about medical importance, bionomics, and distribution are given based on literature records. Adult female of An. galvaoi can be easily misidentified as An. benarrochi Gabald n and An. aquasalis Curry. A few characters are indicated for identifying female and immatures of An. galvaoi. Phylogenetic relationships among An. galvaoi and six other species of the Oswaldoi Subgroup are estimated using COII mtDNA and ITS2 rDNA gene sequences. Lectotype of An. galvaoi, an adult female from Rio Branco, State of Acre, is invalidated.


Assuntos
Anopheles/anatomia & histologia , Animais , Anopheles/classificação , Anopheles/genética , Brasil , Feminino , Masculino , Filogenia , Caracteres Sexuais
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