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Lileia Diotaiuti - One of the best experts on this subject based on the ideXlab platform.
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assessing the mitochondrial dna diversity of the chagas disease vector Triatoma sordida hemiptera reduviidae
Memorias Do Instituto Oswaldo Cruz, 2016Co-Authors: Grasielle Caldas Davila Pessoa, Tais Nobrega De Sousa, Ivan Vieira Sonoda, Lileia DiotaiutiAbstract:Triatoma sordida is a species that transmits Trypanosoma cruzi to humans. In Brazil, T. sordida currently deserves special attention because of its wide distribution, tendency to invade domestic environments and vectorial competence. For the planning and execution of control protocols to be effective against Triatominae, they must consider its population structure. In this context, this study aimed to characterise the genetic variability of T. sordida populations collected in areas with persistent infestations from Minas Gerais, Brazil. Levels of genetic variation and population structure were determined in peridomestic T. sordida by sequencing a polymorphic region of the mitochondrial cytochrome b gene. Low nucleotide and haplotype diversity were observed for all 14 sampled areas; π values ranged from 0.002-0.006. Most obtained haplotypes occurred at low frequencies, and some were exclusive to only one of the studied populations. Interpopulation genetic diversity analysis revealed strong genetic structuring. Furthermore, the genetic variability of Brazilian populations is small compared to that of Argentinean and Bolivian specimens. The possible factors related to the reduced genetic variability and strong genetic structuring obtained for studied populations are discussed in this paper.
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variability of susceptibility to deltamethrin in peridomestic Triatoma sordida from triângulo mineiro state of minas gerais brazil
Revista Da Sociedade Brasileira De Medicina Tropical, 2015Co-Authors: Grasielle Caldas Davila Pessoa, Leticia Sena Dias, Tamara Rodrigues Martins Dos Santos, Gabriela Chadid Salazar, Bernardino Vaz De Mello, Marcela Lencine Ferraz, Lileia DiotaiutiAbstract:Despite chemical and physical vector control strategies, persistent infestations of Triatoma sordida have been reported in a large part of Minas Gerais, Brazil, and the cause for this is little investigated. We aimed to characterize the deltamethrin toxicological profi le in peridomestic T. sordid populations from Triângulo Mineiro area of Minas Gerais. Methods: Susceptibility to deltamethrin was assessed in seventeen peridomestic T. sordida populations. Serial dilutions of deltamethrin in acetone (0.2μL) were topically applied on the fi rst instar nymphs (F1; fi ve days old; fasting weight, 1.2 ± 0.2mg). Dose response results were analyzed using Probit software, and the lethal doses, slope and resistance ratios were determined. Qualitative tests were also performed. Results: The deltamethrin susceptibility profi le of T. sordida populations revealed resistance ratios ranging from 0.84 to 2.8. The percentage mortality in response to a diagnostic dose was 100.0% in all populations. Conclusions: From our results, the lack of resistance to insecticides but persistent T. sordida infestations in the Triângulo Mineiro area may be because of: 1) environmental degradation facilitating dispersion of T. sordida, allowing colonization in artificial ecotopes; 2) operational failures; and 3) complexity of the peridomicile in the study area.These variables are being investigated
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susceptibility of Triatoma sordida stal 1859 hemiptera reduviidae to alpha cypermethrin under natural climatic conditions
Revista Da Sociedade Brasileira De Medicina Tropical, 2015Co-Authors: Grasielle Caldas Davila Pessoa, Aline Cristine Luiz Rosa, Bernardino Vaz De Mello, Leticia Cavalari, Joao Geraldo De Rezende, Lileia DiotaiutiAbstract:INTRODUCTION: Despite the recommendations by interpretation of resistance ratios obtained in laboratory bioassays, little is known about the actual impact of these results in the effectiveness of vector control activities in the field. In this context, our objective was to determine the mean value of different resistance ratios obtained by laboratory bioassays performed as part of the chemical control strategies of Triatoma sordida in the field. METHODS: Field bioassays were developed in Monte Azul and Coracao de Jesus (Southeast, Brazil). In each location, samples were formed with three domestic units treated with alpha-cypermethrin 20.0% (Alfatek (r) 200 SC). One day after spraying, 10 fifth-instar nymphs remained in contact with the surfaces treated (adobe with plaster, adobe without plaster, or wood) with insecticide in plastic cones for 72h. Three cones were exposed inside the intradomicile and the peridomicile. The insects in the control group were exposed to an insecticide-free piece of cardboard. Mortality was measured 72h after removal of the insects from the treated surfaces. The tests were realized in triplicate. RESULTS: Mortality was 100.0% in all locations, except for Monte Azul; Landinho (96.6%) and Coracao de Jesus; Barriguda (96.6%). CONCLUSIONS: Although the resistant populations in laboratory tests proved to be susceptible in the field, this observation is not sufficient to suggest that the cut-off points used to justify the resistance ratio should be changed. In this sense, we recommend that laboratory and field bioassays are carried out with a greater number of Triatominae populations to allow more in-depth consideration of the subject.
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markers for the population genetics studies of Triatoma sordida hemiptera reduviidae
Parasites & Vectors, 2015Co-Authors: Carlota Josefovicz Belisario, Grasielle Caldas Davila Pessoa, Paula Dos F Santos, Leticia Sena Dias, Aline Cristine Luiz Rosa, Lileia DiotaiutiAbstract:Background Triatoma sordida, a vector of Trypanosoma cruzi, is native of Brazil, Bolivia, Paraguay, Argentina, and Uruguay, and occurs primarily in peridomiciles. Currently, it is the species most frequently captured by the Chagas Disease Control Program in Brazil. For this reason, population genetic studies attract great interest, as they can provide further information about the dispersal and household invasion processes of this species. In the absence of suitable markers, the objective of this study was to test the cross amplification of microsatellite primers.
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Markers for the population genetics studies of Triatoma sordida (Hemiptera: Reduviidae)
Parasites & Vectors, 2015Co-Authors: Carlota Josefovicz Belisario, Leticia Sena Dias, Aline Cristine Luiz Rosa, Grasielle Caldas D’Ávila Pessoa, Paula Fernandes Santos, Lileia DiotaiutiAbstract:Background Triatoma sordida , a vector of Trypanosoma cruzi , is native of Brazil, Bolivia, Paraguay, Argentina, and Uruguay, and occurs primarily in peridomiciles. Currently, it is the species most frequently captured by the Chagas Disease Control Program in Brazil. For this reason, population genetic studies attract great interest, as they can provide further information about the dispersal and household invasion processes of this species. In the absence of suitable markers, the objective of this study was to test the cross amplification of microsatellite primers. Findings 23 primers were tested for microsatellite loci already described for other species of the genus Triatoma sp. Forty four specimens of T. sordida captured in the north of Minas Gerais were used to validate the use of standardized loci for population genetic analyses. It was possible to amplify 10 of the 23 loci tested for T. sordida . Conclusions This is the first study that provides 10 microsatellite markers for population analysis of this triatomine species. Cross-amplification of primers can be used among other phylogenetically related species whose loci are already available for study.
Ricardo E Gurtler - One of the best experts on this subject based on the ideXlab platform.
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impacts of residual insecticide spraying on the abundance and habitat occupancy of Triatoma sordida and co occurrence with Triatoma infestans a three year follow up in northeastern argentina
Acta Tropica, 2020Co-Authors: Lucia I Rodriguezplanes, Sol M Gaspe, Gustavo F Enriquez, Ricardo E GurtlerAbstract:Abstract Triatoma infestans, the main vector in the Gran Chaco region, may competitively displace other sympatric species such as Triatoma sordida. We conducted a three-year longitudinal study of site- and house-level infestation and abundance of triatomine bugs before and after an area-wide insecticide spraying campaign followed by sustained vector surveillance in a well-defined rural section of the Argentine Chaco encompassing 368-411 houses. Here, we tested whether insecticide applications targeting and virtually suppressing T. infestans reduced the abundance of T. sordida and modified its habitat occupancies, and whether their joint spatial distribution was random, aggregated or uniform, and varied over time. Systematic timed-manual searches of 18,031 sites yielded 2,226 T. sordida over seven postintervention surveys. Triatoma sordida failed to colonize human sleeping quarters after interventions, and its prime and secondary habitats remained virtually unmodified. Residual insecticide spraying and seasonality best described variations in the house-level abundance of T. sordida as determined using a generalized estimating equation model. Two-species foci occurred in 3.2% of sites ever positive for any species. The habitat-adjusted relative odds of catching one species was 10.8 times greater when the other species was present, with no evidence of heterogeneity among ORs, suggesting no antagonistic interactions throughout the follow-up. The spatial occurrence of both species was significantly aggregated within 300-500 m before and after interventions, and was random at broader spatial scales. The habitat occupancies of T. sordida may be used as a proxy for potential infestation with T. infestans and to guide targeted vector control actions.
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habitat specific occupancy and a metapopulation model of Triatoma sordida hemiptera reduviidae a secondary vector of chagas disease in northeastern argentina
Journal of Medical Entomology, 2018Co-Authors: Ricardo E Gurtler, Lucia I Rodriguezplanes, Sol M Gaspe, Gustavo F EnriquezAbstract:: Triatoma sordida Stal (Hemiptera: Reduviidae), a secondary vector of Trypanosoma cruzi Chagas (Kinetoplastida: Trypanosomatidae), occasionally colonizes human sleeping quarters in Paraguay, Bolivia, and Brazil, whereas only sylvatic and peridomestic populations are found in Argentina. We carried out a cross-sectional survey of house infestation in a well-defined rural area of northeastern Argentina to identify the key habitats of T. sordida; describe its spatial distribution in an apparently undisturbed setting under no recent insecticide treatment and use metapopulation theory to investigate these spatially structured populations. Timed-manual searches in 2,177 georeferenced sites from 368 houses yielded T. sordida in 78 sites (house infestation prevalence, 19.9%). Most triatomines occurred in chicken nests, chicken coops, and trees where chickens roosted (prime habitats). Goat or sheep corrals and pig corrals had a lower fraction of occupied sites (occupancies) and abundance. Both occupancy and catch increased with increasing refuge availability according to multimodel inference with model averaging. The majority of suitable habitats were unoccupied despite their proximity to occupied sites. The site-specific occurrence of T. sordida and Triatoma infestans Klug (Hemiptera: Reduviidae) was positively and homogeneously associated over ecotopes, showing no evidence of interspecific interference. An incidence function metapopulation model (including intersite distances and vector carrying capacity) predicted a fivefold greater occupancy relative to the observed pattern, suggesting the latter represented a transient state. T. sordida failed to colonize human sleeping quarters, thrived in peridomestic habitats occupied by chickens, and had a limited occupancy likely related to a poor colonizing ability and the relative instability of its prime habitats.
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trypanosoma cruzi infection in Triatoma sordida before and after community wide residual insecticide spraying in the argentinean chaco
Acta Tropica, 2015Co-Authors: Natalia P Macchiaverna, Ricardo E Gurtler, Gustavo F Enriquez, Maria Sol Gaspe, Laura Tomassone, Marta Victoria CardinalAbstract:Abstract Triatoma sordida is a secondary vector of Trypanosoma cruzi in the Gran Chaco and Cerrado eco-regions where it frequently infests peridomestic and domestic habitats. In a well-defined area of the humid Argentine Chaco, very few T. sordida were found infected when examined by optical microscopic examination (OM). In order to further assess the role of T. sordida and the relative magnitude of subpatent bug infections, we examined the insects for T. cruzi infection, parasite Discrete Typing Units (DTUs) and bloodmeal sources using various molecular techniques. Among 205 bugs with a negative or no OM-based diagnosis, the prevalence of infection determined by kDNA-PCR was nearly the same in bugs captured before (6.3%) and 4 months after insecticide spraying (6.4%). On average, these estimates were sixfold higher than the prevalence of infection based on OM (1.1%). Only TcI was identified, a DTU typically associated with opossums and rodents. Chickens and turkeys were the only bloodmeal sources identified in the infected specimens and the main local hosts at the bugs’ capture sites. As birds are refractory to T. cruzi infection, further studies are needed to identify the infectious bloodmeal hosts. The persistent finding of infected T. sordida after community-wide insecticide spraying highlights the need of sustained vector surveillance to effectively prevent T. cruzi transmission in the domestic and peridomestic habitats.
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direct molecular identification of trypanosoma cruzi discrete typing units in domestic and peridomestic Triatoma infestans and Triatoma sordida from the argentine chaco
Parasitology, 2012Co-Authors: L Maffey, Marta Victoria Cardinal, P C Ordonezkrasnowski, Leonardo Lanati, M A Lauricella, Alejandro G Schijman, Ricardo E GurtlerAbstract:We assessed the distribution of Trypanosoma cruzi Discrete Typing Units (DTUs) in domestic and peridomestic Triatoma infestans and Triatoma sordida specimens collected in a well-defined rural area in Pampa del Indio, northeastern Argentina. Microscopically-positive bugs were randomly selected with a multi-level sampling design, and DTUs were identified using direct PCR strategies. TcVI predominated in 61% of 69 T. infestans and in 56% of 9 T. sordida. TcV was the secondary DTU in T. infestans (16%) and was found in one T. sordida specimen (11%). Three T. sordida (33%) were found infected with TcI, a DTU also identified in local Didelphis albiventris opossums. Mixed DTU infections occurred rarely (5%) and were detected both directly from the bugs’ rectal ampoule and parasite cultures. The identified DTUs and bug collection sites of T. infestans were significantly associated. Bugs infected with TcV were almost exclusively captured in domiciles whereas those with TcVI were found similarly in domiciles and peridomiciles. All mixed infections occurred in domiciles. TcV-infected bugs fed more often on humans than on dogs, whereas TcVI-infected bugs showed the reverse pattern. T. sordida is a probable sylvatic vector of TcI linked to D. albiventris, and could represent a secondary vector of TcVI and TcV in the domestic/peridomestic cycle.
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A simple method to identify triatomine (Hemiptera: Reduviidae) feces in sensing devices used in vector surveillance programs.
Journal of Medical Entomology, 2001Co-Authors: Ricardo E Gurtler, M. L. Oneto, María C. Cecere, M. B. Castañera, Delmi Margarita CanaleAbstract:Abstract We successfully applied the phenolphthalin (Kastle–Meyer) test used in forensic chemistry to distinguish between feces from triatomines and other domestic arthropods in sensing devices used for vector surveillance. All black or dark brown, but not white or yellow, fecal smears from laboratory-reared or field-collected Triatoma infestans Klug, Triatoma guasayana Wydgozinsky & Abalos, Triatoma sordida Stahl (recently revalidated as Triatoma garciabesi Carcavallo, Cichero, Martinez, Prosen & Ronderos) tested positive, whereas dejecta from cockroaches and spiders, crickets, beetles, predatory bugs, and domestic flies tested negative. Black or dark brown dejecta from female Aedes aegypti L. and Cimex lectularius L. bedbugs also tested positive. In sensing devices installed in bedrooms of 11 houses in Amama, rural northwestern Argentina, where neither cimicid bedbugs nor argasid ticks had been found over the years, only 62% of the black or dark brown fecal smears attributed to triatomines by a skilled ...
Francois Noireau - One of the best experts on this subject based on the ideXlab platform.
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cryptic speciation in the Triatoma sordida subcomplex hemiptera reduviidae revealed by chromosomal markers
Parasites & Vectors, 2015Co-Authors: Francisco Panzera, Sebastian Pita, Julieta Nattero, Yanina Panzera, Cleber Galvao, Tamara Chavez, Antonieta Rojas De Arias, Lourdes Cardozo Tellez, Francois NoireauAbstract:Background Chagas disease vectors (Hemiptera-Reduviidae) comprise more than 140 blood-sucking insect species of the Triatominae subfamily. The largest genus is Triatoma, subdivided in several complexes and subcomplexes according to morphology, ecology and genetic features. One of them is the sordida subcomplex, involving four species: Triatoma sordida, T. guasayana, T. garciabesi and T. patagonica. Given the great morphological similarity of these species, their taxonomic identification, evolutionary relationships and population differentiation have been controversial for many years and even today remain under discussion.
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Cryptic speciation in the Triatoma sordida subcomplex (Hemiptera, Reduviidae) revealed by chromosomal markers
Parasites & Vectors, 2015Co-Authors: Francisco Panzera, Sebastian Pita, Julieta Nattero, Yanina Panzera, Cleber Galvao, Tamara Chavez, Antonieta Rojas De Arias, Lourdes Cardozo Téllez, Francois NoireauAbstract:Background Chagas disease vectors (Hemiptera-Reduviidae) comprise more than 140 blood-sucking insect species of the Triatominae subfamily. The largest genus is Triatoma , subdivided in several complexes and subcomplexes according to morphology, ecology and genetic features. One of them is the sordida subcomplex, involving four species: Triatoma sordida, T. guasayana , T. garciabesi and T. patagonica . Given the great morphological similarity of these species, their taxonomic identification, evolutionary relationships and population differentiation have been controversial for many years and even today remain under discussion. Methods We simultaneously analyzed two chromosomal markers, C-heterochromatin distribution and 45S ribosomal genes chromosomal position, of 139 specimens from several sordida subcomplex populations from Argentina, Bolivia, Brazil and Paraguay, collected both in nature and from several established insectaries. Our results were compared with COI sequences deposited in GenBank. Results We recognized five chromosomal taxa with putative hybrids, which each differ in at least one chromosome marker. Most of them present significant differences in their mtDNA sequences. Conclusion The chromosomal taxa here show a significant chromosome differentiation involving changes in the C-heterochromatin content and in the ribosomal clusters position. This paper identifies several erroneously classified populations by morphological methods, delimits the geographical distribution of each taxon and proposes the existence of a new cryptic species, widely distributed in Argentina. We also suggest that sordida sibling species involve closely related as well as evolutionary distant species. Taxonomic status of each chromosomal taxon is discussed considering phenotypic and genetic results previously published.
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New Discoveries of Sylvatic Triatoma infestans (Hemiptera: Reduviidae) Throughout the Bolivian Chaco
American Journal of Tropical Medicine and Hygiene, 2012Co-Authors: Etienne Waleckx, Francois Noireau, Stéphanie Depickère, Renata Salas, Claudia Aliaga, Marcelo Monje, Hiber Calle, Rosio Buitrago, Simone Frederique BreniereAbstract:Sylvatic populations of Triatoma infestans might be involved in the recolonization of human dwellings. We report here the discoveries of new T. infestans sylvatic foci in the Bolivian Chaco. Eighty-one triatomines were caught, 38 of which were identified as T. infestans. Triatoma sordida and Panstrongylus geniculatus were the other species collected. One T. infestans and one T. sordida were infected with Trypanosoma cruzi TcI; one T. infestans was infected with TcII. These discoveries add to the debate on the geographic distribution of sylvatic T. infestans populations, the geographic origin of the species, and the epidemiological role of these populations.
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flight and nutritional status of sylvatic Triatoma sordida and Triatoma guasayana
Memorias Do Instituto Oswaldo Cruz, 2001Co-Authors: Francois Noireau, J P DujardinAbstract:Nutritional status relating to flight activity was investigated in natural populations of Triatoma sordida and T. guasayana during the dry season in the Bolivian Chaco. The peak flight activity of both species was unimodal and covered the period 61-180 min after sunset. The weight of insects was used as the indicator of nutritional status. Interspecies comparisons employing the same sex and type of capture showed a higher weight for T. guasayana. No significant difference according to weight was observed between flying insects and those collected in natural ecotopes (hollow trees and bromeliads). More than 87% of insects collected from natural ecotopes displayed flight ability under the study conditions, explaining their tendency to invade artificial structures during the dry season.
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genetic structure of Triatoma sordida hemiptera reduviidae domestic populations from bolivia application on control interventions
Memorias Do Instituto Oswaldo Cruz, 1999Co-Authors: Francois Noireau, T Gutierrez, Mario Zegarra, Jackline Ordonez, J P DujardinAbstract:The genetic population of Triatoma sordida group 1, a secondary vector of Chagas disease in Bolivia, was studied by multi-locus enzyme electrophoresis. A total of 253 nymphal and adult specimens collected from seven neighbouring localities in the Velasco Province, Department of Santa Cruz, were processed. The relatively low genetic variability was confirmed for this species (rate of polymorphism: 0.20). The absence of genetic disequilibrium detected within the seven localities was demonstrated. A geographical structuration appears between localities with distances greater than 20 km apart. Although T. sordida presents a relatively reduced dispersive capacity, its panmictic unit is wider than compared with T. infestans. Genetic distances between T. sordida populations were correlated with geographic distance. Gene flow between geographic populations of T. sordida provides an efficient framework for effective vigilance and control protocols.
Cristina Wisniveskycolli - One of the best experts on this subject based on the ideXlab platform.
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Triatoma sordida stal 1859 hemiptera reduviidae triatominae in palms of northeastern argentina
Memorias Do Instituto Oswaldo Cruz, 2001Co-Authors: Cristina WisniveskycolliAbstract:Several palms species provide an important habitat for triatomines and associate vertebrates in tropical America. The objective of this work is to identify the triatomine species living in the palms of rural areas in the Province of Corrientes, and to estimate the potential epidemiological risk they represent for the residents of nearby houses. The survey was carried out in a palm community in Colonia Laurel, Department San Roque, Province of Corrientes, Argentina. Samplings were performed in October, November and December 1998; January, February and March 1999; May and June 1999. Thirty palms: 27 (90%) Butia yatay (Mart.) Becc. and 3 Acrocomia aculeata (Jacq.) Lodd ex Mart. were dissected. Triatoma sordida Stal 1859 was found in 96.2% of B. yatay and in all the A. aculeata palms. A total of 272 live T. sordida was collected; 36 of them (13.2%) were found in bird nests in the frond and the remainder in other locations of the tree. The mean number of triatomines per palm was 9.6 (range 1-60, mode 2). T. sordida was collected during all the sampling months and all stages were present at all seasons. The highest population density was reached in spring and the lowest in autumn. Trypanosoma cruzi was detected in 38.5% in feces of 174 examined insects and identified as such, both by microscopical examination and PCR. This is the first finding of T. sordida populations in B. yatay, an endemic palm of South America distributed in southern Brazil, Uruguay and northeastern Argentina. The high infection prevalence found in this work suggests that T. sordida plays an essential role in the maintenance of the wild T. cruzi transmission cycle in northeastern Argentina.
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interactions between Triatoma infestans and Triatoma sordida hemiptera reduviidae in artificial ecotopes population growth and age structure
Journal of Medical Entomology, 2001Co-Authors: E B Oscherov, Miryam P Damborsky, Benedicta Mabel Alvarez, Gilberto Avalos, Hilda Presman, Cristina WisniveskycolliAbstract:Interaction characteristics between Triatoma infestans Klug, 1834 and Triatoma sordida Stal, 1859 populations were studied in artificial ecotopes for 16 mo. The experimental design involved simultaneous treatments with T. infestans and T. sordida together in the same experimental unit (EU) and each separately in two control units (CU) made of adobe bricks. Chickens were used as host animals. Each unit was dismantled monthly to estimate triatomine population size and age structure, rebuilt, and repopulated with the same insects. In both units, T. infestans population growth followed a logistic model, whereas T. sordida did not show this pattern. T. infestans completed a generation in 24 wk (EU) and 32 wk (CU1), whereas T. sordida did not complete one generation during this period. We concluded that T. infestans showed a better colonizing success than T. sordida. After living together for 1 yr, an interference process took place that resulted in the extinction of T. sordida.
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comparative meiotic studies in Triatoma sordida stal and t guasayana wygodzinsky abalos reduviidae heteroptera
Memorias Do Instituto Oswaldo Cruz, 1998Co-Authors: Pablo Javier Rebagliati, A G Papeschi, L M Mola, Silvia Pietrokovsky, Patricia P Gajate, Victoria Bottazzi, Cristina WisniveskycolliAbstract:Triatoma sordida and T. guasayana are competent Trypanosoma cruzi vectors, with overlapping distribution areas in Argentina. Both species are morphologically similar, and their immature stages are hard to discriminate. Cytogenetic studies in the genus Triatoma reveal scarce karyotypic variations, being 2n= 20 + XY the most frequent diploid number in males. In the present work the meiotic behaviour of different Argentinian populations of T. sordida and T. guasayana has been analyzed; the meiotic karyotype of both species has also been compared. The species differ in total chromosome area and in the relative area of the sex chromosomes. These meiotic karyotypic differences constitute an additional tool for the taxonomic characterization of T. sordida and T. guasayana. The analysis of an interpopulation hybrid of T. sordida (Brazil x Argentina) reveals a regular meiotic behaviour, despite the presence of heteromorphic bivalents. Our observations support the hypothesis that karyotype variations through the gain or loss of heterochromatin can not be considered as a primary mechanism of reproductive isolation in Triatoma.
Joao Aristeu Da Rosa - One of the best experts on this subject based on the ideXlab platform.
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genetic structure of brazilian populations of Triatoma sordida stal 1859 hemiptera triatominae by means of chromosomal markers
American Journal of Tropical Medicine and Hygiene, 2019Co-Authors: Fernanda Fernandez Madeira, Jader De Oliveira, Joao Aristeu Da Rosa, Yago Visinho Dos Reis, Isadora De Freitas Bittinelli, Luiza Maria Grzyb Delgado, Vagner Jose Mendonca, Felipe Ferraz Figueiredo Moreira, Maria Tercilia Vilela De Azeredooliveira, Kaio Cesar Chaboli AleviAbstract:Triatoma sordida is among the main Brazilian species considered as Chagas disease vectors. The genetic studies are directed mainly to phylogenetic questions because this species possibly have suffered cryptic speciation. Furthermore, there are few studies that analyzed the structure and genetic variability of specimens from Brazil and that showed low genetic diversity and strong genetic structuring of the population samples. Therefore, because of great epidemiological importance of T. sordida and mainly the restriction of genetic characterization of this vector only for populations of Minas Gerais state, this article performs a genetic analysis of the T. sordida from seven different Brazilian states (representing different biomes), by means of cytogenetic markers. All analyzed specimens presents the same cytogenetic characteristics: early meiotic prophase with several heterochromatic bodies dispersed in the nucleus (CG-rich), being one of them formed by the associated sex chromosomes surrounded by some autosomal heterochromatic regions, meiotic metaphase with most autosomal pairs exhibiting a C-heterochromatic block in one chromosomal end (CG-rich), Y sex chromosome fully heterochromatin (AT-rich), and X chromosome may present a small C-block (CG-rich). These results are important because the chromosomal markers enable to confirm and expand the low genetic diversity for all Brazilian states occupied by T. sordida, suggesting that all Brazilian populations were originated from a small ancestral population and possibly dispersed to other biomes by founder effect. In addition, we suggest that T. sordida from Brazil are not suffering cryptic speciation and we confirm the classification of all Brazilian examples as T. sordida sensu stricto.
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first report of Triatoma sordida stal 1859 hemiptera reduviidae triatominae in the state of acre and brazilian western amazon
Revista Da Sociedade Brasileira De Medicina Tropical, 2018Co-Authors: Leandro Jose Ramos, Janis Lunier De Souza, Claudio Rodrigues De Souza, Jader De Oliveira, Joao Aristeu Da Rosa, Luis Marcelo Aranha Camargo, Renildo Moura Da Cunha, Dionatas Ulises De Oliveira MeneguettiAbstract:INTRODUCTION: The occurrence of Triatoma sordida in the Brazilian Western Amazon is reported for the first time. METHODS: Triatoma sordida specimens were collected from a Gallus gallus nest in a peridomiciliary area of Senador Guiomard municipality in the state of Acre. RESULTS: The number of triatomine species in Acre increased from six to seven with this first report of T. sordida in the Brazilian Western Amazon. CONCLUSIONS: The occurrence of T. sordida in Acre is of concern since it is among the most captured triatomines in peridomiciliary environments in Brazil, and carries a high potential for vector transmission.
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cb 12 estudo da genitalia externa feminina de tres especies do subcomplexo Triatoma sordida hemiptera reduviidae triatominae utilizando microscopia eletronica de varredura
Journal of Basic and Applied Pharmaceutical Sciencies, 2015Co-Authors: Tiago Belintani, Jader De Oliveira, Juliana Damieli Nascimento, Joao Aristeu Da RosaAbstract:Introducao: A doenca de Chagas e uma das enfermidades mais graves do continente americano e os estudos de seus vetores se fazem necessarios, de modo a contribuir para o entendimento das relacoes biologicas, evolutivas e epidemiologicas. Objetivo: Este trabalho teve como objetivo estudar morfologicamente a genitalia feminina externa de tres especies do subcomplexo Triatoma sordida: Triatoma garciabesi, duas populacoes distintas de Triatoma guasayana, provenientes da Provincia de Santa Cruz (Argentina) e Provincia de Tita (Bolivia) e Triatoma sordida, especies relacionadas pelas caracteristicas morfologicas. Metodologia: Os especimes utilizados sao mantidos no Insetario de Triatominae da Faculdade de Ciencias Farmaceuticas/UNESP. Os estudos morfologicos foram realizados por meio de exame macroscopico e por microscopia eletronica de varredura (MEV). Para obter as imagens da genitalia externa feminina (vista dorsal, posterior e ventral), as amostras foram previamente preparadas e examinadas em MEV - Topcon SM-300, como descrito em Rosa et al, 2010. O estudo comparativo foi realizado por meio de imagens de quatro amostras. Resultados e Discussao: Os resultados obtidos por MEV mostram que o nono e decimo segmentos dorsais de T. garciabesi e T. sordida possuem forma alongada com o decimo segmento arredondado; para T. guasayana (Argentina), o decimo segmento apresentou forma trapezoidal e o nono segmento alongado; a amostra de T. guasayana (Bolivia) apresentou nono segmento pouco alongado com o decimo segmento arredondado. Sob o ponto de vista ventral, as especies apresentaram caracteristicas distintivas na forma e tamanho dos gonapofises e gonocoxitos, bem como no nono e decimo segmento, sendo que os gonapofises de T. garciabesi e T sordida sao triangulares e nas extremidades finais levemente ovalados em T. garciabesi; em T. guasayana (Argentina), as superficies dos gonapofises sao concavas e com a face interna bem retilinea; para T. guasayana (Bolivia), nota-se que os gonapofises sao bem reduzidos e os gonocoxitos menores e menos alongados. A linha final do setimo segmento apresentou semelhancas entre T. garciabesi, T. guasayana (Bolivia) e T. sordida, sendo curvadas nas extremidades e elevadas no meio, bem como T. guasayana (Argentina), que apresentou a linha final do setimo segmento retilinea nas extremidades, formando um triângulo. Com base na perspectiva posterior, notamos diferencas na forma e dimensao do gonocoxitos e gonapofises, bem como o nono segmento, que e convexo para T. garciabesi, T. guasayana (Argentina) e T. sordida e concavo para T. guasayana (Bolivia). Conclusoes: Dadas as dificuldades de identificacao especifica entre as especies do subcomplexo Triatoma sordida, este estudo sugere que as genitalias externas femininas sao uteis para caracterizacao especifica, bem como para estudos taxonomicos e filogeneticos do complexo T. sordida, assim como da subfamilia Triatominae.
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Triatominae Survey (Hemiptera: Reduviidae: Triatominae) in the South-Central Region of the State of Bahia, Brazil Between 2008 and 2013
American Journal of Tropical Medicine and Hygiene, 2015Co-Authors: Vagner Jose Mendonca, Aline Rimoldi, Renato Freitas De Araujo, J. Oliveira, Júlio César Rente Ferreira Filho, Joao Aristeu Da RosaAbstract:Triatomine surveillance in rural areas, artificial ecotypes, and natural ecotopes of the cities of Caturama, Ibipitanga, Macaubas, and Seabra in the south-central region of the Brazilian state of Bahia was carried out between 2008 and 2013. Natural infection by Trypanosoma cruzi was evaluated in the specimens collected to monitor vectors of Chagas disease. A total of 1,357 specimens were collected, and four species were identified: Triatoma sordida (83%), Triatoma lenti (16.4%), Triatoma pseudomaculata (0.5%), and Panstrongylus geniculatus (0.1%). Triatoma sordida was found in four cities, only 0.7% in intradomiciliary environments. Triatoma lenti was found only in Macaubas; 8.5% were found in intradomiciliary environments, 88.3% in peridomiciliary environments, and 3.1% in sylvatic environments. Natural infection by T. cruzi was 0.5% for T. sordida and 3.1% T. lenti. All of these cases were found in peridomiciliary environments of Macaubas. As the results show, triatomines were found in intradomiciliary environments in three cities that were surveyed in the south-central region of the state of Bahia. Thus, an epidemiologic survey should be performed to avoid the risk of transmission to the population.
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morphological biological and molecular characterization of three strains of trypanosoma cruzi chagas 1909 kinetoplastida trypanosomatidae isolated from Triatoma sordida stal 1859 hemiptera reduviidae and a domestic cat
Parasitology, 2012Co-Authors: Aline Rimoldi, Renata Tome Alves, Daniela Luz Ambrosio, Maria Zenaide Tita Fernandes, Isabel Martinez, Renato Freitas De Araujo, Regina Maria Barreto Cicarelli, Joao Aristeu Da RosaAbstract:A study was conducted of the biological, morphological and molecular characters of 3 strains of Trypanosoma cruzi (SI5, SI8 and SIGR3) isolated from specimens of Triatoma sordida collected in Santo Inacio and a domestic cat. In order to carry out the study, the following parameters were evaluated: pre-patent period, parasitaemia curves, morphology of the parasites, mortality rates, histopathological lesions and molecular typing. The strains presented variable pre-patent periods, low parasitaemia and no animal mortality. The morphological study of trypomastigotes showed a predominance of intermediate-width and short-length forms, as well as low nuclear index. Epimastigotes presented a low nuclear index, intermediate-width forms in strains SI5 and SI8, and large-width forms in SIGR3. A shorter length could be noted in strains SI8 and SIGR3, whereas SI5 displayed an intermediate length. The histopathological study did not detect amastigote nests in tissues. The amplification of the divergent domain of 24Sα rRNA, HSP60 and GPI genes of strains SI5, SI8 and SIGR3 classified the 3 strains into Group II. Biological parameters made it possible to classify the strains isolated in Santo Inacio (BA) into Biodeme III, Zymodeme 1 and Group II of T. cruzi.
