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Viana MC, Alves-Pereira A, Oliveira MAP, Valença-Barbosa C, Folly-Ramos E, Souza AP, Takiya DM, Almeida CE. Population genetics and genomics of Triatoma brasiliensis (Hemiptera, Reduviidae) in an area of high pressure of domiciliary infestation in Northeastern Brazil. Acta Trop 2024; 252:107144. [PMID: 38336343 DOI: 10.1016/j.actatropica.2024.107144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Understanding the population dynamics of vectors is crucial for effective control of vector-borne diseases. In the Northeastern Brazilian semi-arid region, Triatoma brasiliensis persists as the most significant Chagas disease vector, frequently displaying recurrent domiciliary infestations. This situation raises relevant public health concerns in the municipality of Currais Novos in the state of Rio Grande do Norte. This area has experienced a high prevalence of peridomiciliary re-infestations by T. brasiliensis, coupled with elevated rates of Trypanosoma cruzi infection. Therefore, we assessed the distribution of genetic variation via mitochondrial Cytochrome b gene (MT-CYB) sequencing (n = 109) and single nucleotide polymorphisms (SNPs, n = 86) to assess the gene flow among distinct populations distributed in varied geographic spots and environments, mainly sylvatic and peridomiciliary. Insects were collected from rural communities at Currais Novos, enclosed within a 16 km radius. Sampling included 13 populations: one intradomiciliary, eight peridomiciliary, and four sylvatic. Furthermore, an external population located 220 km from Currais Novos was also included in the study. The method employed to obtain SNP information relied on ddRAD-seq genotyping-by-sequencing (GBS), enabling a genome-wide analysis to infer genetic variation. Through AMOVA analysis of MT-CYB gene variation, we identified four distinct population groups with statistical significance (FCT= 0.42; p<0.05). We identified a total of 3,013 SNPs through GBS, with 11 loci showing putative signs of being under selection. The variation based on 3,002 neutral loci evidenced low genetic structuration based on low FST values (p>0.05), indicating local panmixia. However, resampling algorithms pointed out that three samples from the external population were assigned (>98 %) in a cluster contrasting from the ones putatively under local panmixia - validating the newly applied genome-wide marker for studies on the population genetics at finer-scale resolution for T. brasiliensis. The presence of population structuring in some of the sampled points, as suggested by the mitochondrial marker, leads us to assume that infestations were probably initiated by small populations of females - demographic event poses a risk for rapid re-infestations. The local panmictic pattern revealed by the GBS marker poses a challenge for vector control measures, as re-infestation foci may be distributed over a wide geographical and ecological range. In such instances, vectors exhibit reduced susceptibility to conventional insecticide spraying operations since sylvatic populations are beyond the reach of these interventions. The pattern of infestation exhibited by T. brasiliensis necessitates integrating innovative strategies into the existing control framework, holding the potential to create a more resilient and adaptive vector control program. In our dataset, the results demonstrated that the genetic signals from both markers were complementary. Therefore, it is essential to consider the nature and inheritance pattern of each marker when inferring the pattern of re-infestations.
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Affiliation(s)
- Maria Carolina Viana
- Instituto de Biologia (IB), Universidade de Campinas - UNICAMP, Campinas, Brazil; Programa de Pós-Graduação em Genética e Biologia Molecular, IB, UNICAMP; Coordenação de Prevenção e Vigilância do Câncer (CONPREV), Instituto Nacional de Câncer, Rio de Janeiro, Brazil
| | | | - Marcelo A P Oliveira
- Programa de Pós-Graduação em Genética- IB, Universidade Federal do Rio de Janeiro - UFRJ, Rio de Janeiro, Brazil
| | - Carolina Valença-Barbosa
- Instituto de Biologia (IB), Universidade de Campinas - UNICAMP, Campinas, Brazil; Grupo Triatomíneos, Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Fiocruz, Brazil
| | | | | | | | - Carlos E Almeida
- Instituto de Biologia (IB), Universidade de Campinas - UNICAMP, Campinas, Brazil; Programa de Pós-Graduação em Genética e Biologia Molecular, IB, UNICAMP; Laboratorio de Entomologia, Instituto de Biologia, UFRJ.
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Rivas N, Martínez-Hernández F, Antonio-Campos A, Sánchez-Cordero V, Alejandre-Aguilar R. Genetic diversity in peridomiciliary populations of Triatoma mexicana (Hemiptera: Reduviidae: Triatominae) in central Mexico. Parasitol Res 2022; 121:2875-2886. [PMID: 35930043 DOI: 10.1007/s00436-022-07608-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 07/22/2022] [Indexed: 11/28/2022]
Abstract
Triatoma mexicana is an important vector of Trypanosoma cruzi-the etiological agent of Chagas disease. This triatomine species occurs in central Mexico, but little is known about its genetic variability. Using Cyt-b gene as a genetic marker, in this study, we determined the population genetic structure of T. mexicana collected from the States of Hidalgo, Guanajuato, and Queretaro where populations are largely peridomiciliary. A Bayesian approach was performed for the design of phylogenies, median-joining networks, and clustering among populations of T. mexicana. Our results show that the Hidalgo population was the most distinct, with the highest genetic and haplotypic variation (Hd = 0.963, π = 0.06129, and ɵ = 0.05469). Moderate gene flow (Nm) was determined among populations of Hidalgo and Queretaro. Populations from the three states showed differentiation (FST) values ranging from 0.22 to 0.3, suggesting an important genetic differentiation. The phylogenetic analysis showed the presence of five well-defined groups, as well as the haplotype network, where 24 haplotypes were observed forming five haplogroups with high mutational steps among them: 68 (Hgo-W2), 26 (Qto), 59 (Hgo-M), 44 (Hgo-W1), and 46 (Gto). Genetic isolation was apparently inferred in the Guanajuato population; however, the Mantel test did not show correlation between genetic (FST) and geographic (km) distances (p = 0.05). The STRUCTURE analyses showed seven genetic clusters and it was observed that a single cluster predominates in each sampled location. However, genetic admixture was detected in four localities. Our results show evidence that there are multiple species within the collected sampling area.
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Affiliation(s)
- Nancy Rivas
- Laboratorio de Entomología Médica, Departamento de Parasitología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prol. Carpio Y Plan de Ayala S/N Col. Casco de Santo Tomas, C.P. 11340, Mexico City, CDMX, Mexico
| | - Fernando Martínez-Hernández
- Departamento de Ecología de Agentes Patógenos, Hospital General "Dr. Manuel Gea González", Calzada de Tlalpan 4800, CP 14080, Mexico City, CDMX, Mexico
| | - Alberto Antonio-Campos
- Laboratorio de Entomología Médica, Departamento de Parasitología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prol. Carpio Y Plan de Ayala S/N Col. Casco de Santo Tomas, C.P. 11340, Mexico City, CDMX, Mexico.,Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Copilco 3000, Ciudad Universitaria, Coyoacán, 04510, Mexico City, CDMX, Mexico
| | - Víctor Sánchez-Cordero
- Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Copilco 3000, Ciudad Universitaria, Coyoacán, 04510, Mexico City, CDMX, Mexico
| | - Ricardo Alejandre-Aguilar
- Laboratorio de Entomología Médica, Departamento de Parasitología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prol. Carpio Y Plan de Ayala S/N Col. Casco de Santo Tomas, C.P. 11340, Mexico City, CDMX, Mexico.
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3
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Monsalve-Lara J, Lilioso M, Valença-Barbosa C, Thyssen PJ, Miguel DC, Limeira C, Gadelha FR, Fontes FVHM, Pires-Silva D, Dornak LL, Lima MM, Donalisio MR, Almeida CE. The risk of oral transmission in an area of a Chagas disease outbreak in the Brazilian northeast evaluated through entomological, socioeconomic and schooling indicators. Acta Trop 2021; 215:105803. [PMID: 33373585 DOI: 10.1016/j.actatropica.2020.105803] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 10/22/2022]
Abstract
Chagas disease is a neglected tropical disease strongly associated with low socioeconomic status, affecting nearly 8 million people - mainly Latin Americans. The current infection risk is based on acute case reports, most of which are typically associated with oral transmissions. In the semi-arid region of Northeastern Brazil, serious outbreaks of this transmission type have surged in the last years. One of those occurred in 2016 in the state of Rio Grande do Norte. Rural residents of four municipalities surrounding Marcelino Vieira ingested sugar cane juice - which was probably ground with Trypanosoma cruzi-infected insects. Eighteen cases of Chagas disease were confirmed serologically, with two deaths reported. Socioeconomic information, schooling of residents and the structure of peridomestic and domestic environments in the rural area of Marcelino Vieira, along with entomological indicators, were investigated to understand better the factors related to the outbreaks in this region. We found triatomines (mainly Triatoma brasiliensis) in 35% (24/67) of domiciliary units and all rocky outcrops inspected (n = 7). Overall, 25% (91/357) of examined T. brasiliensis were infected by T. cruzi in artificial ecotopes, with almost the same prevalence in the sylvatic environment (22%; 35/154). Among all ecotopes investigated, wood/tile/brick piles were the ones linked to high insect infestations and triatomine T. cruzi infection prevalence. Ninety-five percent of people interviewed recognized the triatomines and knew the classic route of transmission of disease - triatomine bite-dependent. However, only 7.5% admitted knowledge that Chagas disease can also be acquired orally - which poses a risk this transmission route currently recognized. Here, we highlight the physical proximity between humans and triatomine populations with high T. cruzi infection prevalence as an additional risk factor to oral/vector contaminations. In sum, residents have low income, low level of education, and/or a willful disregard for the routes of Chagas disease transmission (specifically oral transmission), a combination of factors that may have favored the Chagas disease outbreak. We here provide recommendations to avoid further outbreaks.
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Kamimura EH, Viana MC, Lilioso M, Fontes FHM, Pires-Silva D, Valença-Barbosa C, Carbajal-de-la-Fuente AL, Folly-Ramos E, Solferin VN, Thyssen PJ, Costa J, Almeida CE. Drivers of molecular and morphometric variation in Triatoma brasiliensis (Hemiptera: Triatominae): the resolution of geometric morphometrics for populational structuring on a microgeographical scale. Parasit Vectors 2020; 13:455. [PMID: 32894173 PMCID: PMC7487581 DOI: 10.1186/s13071-020-04340-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 09/01/2020] [Indexed: 11/24/2022] Open
Abstract
Background The protozoan Trypanosoma cruzi circulates in semiarid areas of northeastern Brazil in distinct ecotopes (sylvatic, peridomestic and domestic) where Triatoma brasiliensis Neiva, 1911 is the most important Chagas disease vector. In this study, we analyzed microevolutionary and demographic aspects of T. brasiliensis populations at the ecotypic, micro and macro-geographic scales by combining morphometrics and molecular results. Additionally, we aimed to address the resolution of both markers for delimiting populations in distinct scales. Methods We sampled populations of T. brasiliensis from distinct ecotypic and geographic sites in the states Rio Grande do Norte (RN) and Paraíba (PB). The geometric morphometry was carried out with 13 landmarks on the right wings (n = 698) and the genetic structure was assessed by sequencing a region of cytochrome b mitochondrial gene (n = 221). Mahalanobis distance (MD) and coefficient of molecular differentiation (ΦST) were calculated among all pairs of populations. The results of comparisons generated MD and ΦST dendrograms, and graphics of canonical variate analysis (CVA). Results Little structure was observed for both markers for macro-geographic scales. Mantel tests comparing geographic, morphometric and genetic matrices showed low correlation (all R2 < 0.35). The factorial graphics built with the CVA evidenced population delimitation for the morphometric data at micro-geographic scales. Conclusions We believe that T. brasiliensis carries in its genotype a source of information to allow the phenotypical plasticity across its whole distribution for shaping populations, which may have caused a lack of population delimitation for CVAs in morphometric analysis for macro-geographic scale analysis. On the other hand, the pattern of morphometric results in micro-geographic scales showed well-defined groups, highlighting the potential of this tool to inferences on the source for infestation.![]()
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Affiliation(s)
- Edgard H Kamimura
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Maria Carolina Viana
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Maurício Lilioso
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Fernanda H M Fontes
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Dayane Pires-Silva
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | | | - Ana L Carbajal-de-la-Fuente
- Centro Nacional de Diagnóstico e Investigación en Endemo-Epidemias (CeNDIE), Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos Malbrán" (ANLIS), Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | | | - Vera N Solferin
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Patricia J Thyssen
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (IOC/Fiocruz-RJ), Rio de Janeiro, Brazil
| | - Carlos E Almeida
- Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil.
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Lilioso M, Reigada C, Pires-Silva D, Fontes FVHM, Limeira C, Monsalve-Lara J, Folly-Ramos E, Harry M, Costa J, Almeida CE. Dynamics of food sources, ecotypic distribution and Trypanosoma cruzi infection in Triatoma brasiliensis from the northeast of Brazil. PLoS Negl Trop Dis 2020; 14:e0008735. [PMID: 32986738 PMCID: PMC7575107 DOI: 10.1371/journal.pntd.0008735] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 10/20/2020] [Accepted: 08/19/2020] [Indexed: 12/15/2022] Open
Abstract
Innovative approaches used to combat Chagas disease transmission tend to combine a set of comprehensive efforts to understand the ecology of local vectors. In this work we identified molecularly the blood meal of 181 Triatoma brasiliensis, distributed in 18 populations (8 sylvatic and 10 peridomestic), which were collected across a range of 240 km (East-West) and 95 km (North-South) in the semi-arid region of northeastern, Brazil. We used the vertebrate mitochondrial gene (cytochrome B) sequencing applied to DNA isolated from bug midgut to identify the insect blood meal sources via the BLAST procedure. The peridomestic populations were classified according to two main hypotheses of site-occupancy for T. brasiliensis: the first says that the infestation is mainly driven by structures that resemble its natural habitat (stony-like ecotopes) and the second assumes that it is associated with key-hosts (rodents and goats). Rodents of the Caviidae family (Galea spixii and Kerodon rupestris) were identified as the key-host of T. brasiliensis, but also the potential Trypanosoma cruzi reservoir-able to connect the sylvatic and domestic T. cruzi cycle. Cats also deserve to be studied better, as potential T. cruzi reservoirs. By modeling the food sources + site-occupancy + T. cruzi natural infection, we identified man-made ecotopes suitable for forming dense triatomine infestations with high rates of T. cruzi natural infection, which may be taken into account for vector control measures.
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Affiliation(s)
- Maurício Lilioso
- Instituto de Biologia, Universidade Estadual de Campinas – UNICAMP, Brazil
| | - Carolina Reigada
- Centro de Ciências Biológicas e da Saúde, Departamento de Ecologia e Biologia Evolutiva, Universidade Federal de São Carlos – UFSCAR, Brazil
| | - Dayane Pires-Silva
- Instituto de Biologia, Universidade Estadual de Campinas – UNICAMP, Brazil
| | | | - Cleanne Limeira
- Instituto de Biologia, Universidade Estadual de Campinas – UNICAMP, Brazil
| | | | | | - Myriam Harry
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, Gif-sur-Yvette, France
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil, Manguinhos, Rio de Janeiro, Brazil
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Bezerra CM, Belisário CJ, D'Ávilla Pessoa GC, Rosa ACL, Barezani CP, Ferreira FC, Ramos AN, Gürtler RE, Diotaiuti L. Microsatellite variation revealed panmictic pattern for Triatoma brasiliensis (Triatominae: Reduviidae) in rural northeastern Brazil: the control measures implications. BMC Genet 2020; 21:92. [PMID: 32854614 PMCID: PMC7457261 DOI: 10.1186/s12863-020-00903-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 08/17/2020] [Indexed: 01/01/2023] Open
Abstract
Background Triatoma brasiliensis Neiva, 1911 is the main vector of Trypanosoma cruzi in the caatinga of Northeastern Brazil. Despite of its epidemiological relevance, there are few studies on its genetic variability. Using microsatellite markers, we characterized the variability and dynamics of infestation and reinfestation of T. brasiliensis after residual insecticide spraying in five surveys conducted in a well-defined rural area located in the municipality of Tauá, Ceará, between 2009 and 2015. We evaluated: (1) general variability among local of captures; (2) variability along the time analysis (2009, 2010 and 2015); (3) and reinfestation process. Results On the analysis (1) global and pairwise FST values suggested absence of clusters among the area. AMOVA indicated that total variation is mainly represented by individual differences. Absence of clustering indicates a panmitic unit, with free gene flow. For (2), Pairwise FST indicated alterations in the genetic profile of the triatomines along the time. (3) Analysis of the reinfestation process showed that the domiciliary units investigated had different sources of infestation despite of its proximity. Conclusions Observed homogeneity can be explained by the great dispersal capacity of T. brasiliensis, overlapping the different environments. Persistent house infestation in Tauá may be attributed to the occurrence of postspraying residual foci and the invasion of triatomines from their natural habitats.
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Affiliation(s)
- Claudia Mendonça Bezerra
- Departamento de Saúde Comunitária. Rua Professor Costa Mendes 1608 - Bloco Didático 5° andar - Rodolfo Teófilo, Universidade Federal do Ceará, Faculdade de Medicina, Fortaleza, Ceará, CEP: 60430-140, Brazil. .,Secretaria da Saúde do Estado do Ceará, Fortaleza, CE, Brazil.
| | - Carlota Josefovicz Belisário
- Grupo de Pesquisa em Triatomíneos e Epidemiologia da Doença de Chagas, Instituto René Rachou / FIOCRUZ - MG, Belo Horizonte, MG, Brazil
| | | | - Aline Cristine Luiz Rosa
- Grupo de Pesquisa em Triatomíneos e Epidemiologia da Doença de Chagas, Instituto René Rachou / FIOCRUZ - MG, Belo Horizonte, MG, Brazil
| | - Carla Patrícia Barezani
- Grupo de Pesquisa em Triatomíneos e Epidemiologia da Doença de Chagas, Instituto René Rachou / FIOCRUZ - MG, Belo Horizonte, MG, Brazil
| | - Flávio Campos Ferreira
- Grupo de Pesquisa em Triatomíneos e Epidemiologia da Doença de Chagas, Instituto René Rachou / FIOCRUZ - MG, Belo Horizonte, MG, Brazil
| | - Alberto Novaes Ramos
- Departamento de Saúde Comunitária. Rua Professor Costa Mendes 1608 - Bloco Didático 5° andar - Rodolfo Teófilo, Universidade Federal do Ceará, Faculdade de Medicina, Fortaleza, Ceará, CEP: 60430-140, Brazil
| | - Ricardo Esteban Gürtler
- Laboratory of Eco-Epidemiology, Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, C1428EHA, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA). Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Ciudad Universitaria, C1428EHA, Buenos Aires, Argentina
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7
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de Oliveira J, Chaboli Alevi KC, Almeida CE, Mendonça VJ, Costa J, da Rosa JA. Triatoma brasiliensis species complex: characterization of the external female genitalia. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2020; 45:57-68. [PMID: 32492272 DOI: 10.1111/jvec.12373] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 01/25/2020] [Indexed: 06/11/2023]
Abstract
The Triatoma brasiliensis complex is composed of six species (Triatoma bahiensis, T. juazerensis, T. lenti, T. melanica, T. petrocchiae, and T. sherlocki) and two subspecies (T. brasiliensis brasiliensis and T. b. macromelasoma). Phylogenetic studies have shown that it is a monophyletic group, but the morphological relationships among the members can be better understood. We applied a tool of high resolution based on morphology to identify details that characterize the female genitals for each member of this group. The external genital structures of five to fifteen females of each taxon were analyzed. Insects had their abdomen transversely cut to separate the last abdominal segments, and representative illustrations obtained via scanning electron microscopy (SEM) are shown. Observations were performed in the dorsal and the ventral views. The morphological characterization of female external genitalia allowed a differentiation of each species/subspecies. The subspecies T. b. brasiliensis and T. b. macromelasoma were the most similar. On the other hand, dorsal view of structures evidenced some unique characteristics for T. petrocchiae and T. sherlocki. Regarding these structures for T. petrocchiae, the differentiation was in accordance with molecular studies, since this species exhibits the highest genetic distances in relation to other species of T. brasiliensis complex.
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Affiliation(s)
- Jader de Oliveira
- Universidade Estadual Paulista (UNESP), Faculdade de Ciências Farmacêuticas, Campus Araraquara, São Paulo, Brasil
| | - Kaio Cesar Chaboli Alevi
- Universidade Estadual Paulista (UNESP), Faculdade de Ciências Farmacêuticas, Campus Araraquara, São Paulo, Brasil
| | | | | | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz (IOC), FIOCRUZ, Brasil
| | - João Aristeu da Rosa
- Universidade Estadual Paulista (UNESP), Faculdade de Ciências Farmacêuticas, Campus Araraquara, São Paulo, Brasil
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8
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Lima-Oliveira TM, Fontes FVHM, Lilioso M, Pires-Silva D, Teixeira MMG, Meza JGV, Harry M, Fileé J, Costa J, Valença-Barbosa C, Folly-Ramos E, Almeida CE. Molecular eco-epidemiology on the sympatric Chagas disease vectors Triatoma brasiliensis and Triatoma petrocchiae: Ecotopes, genetic variation, natural infection prevalence by trypanosomatids and parasite genotyping. Acta Trop 2020; 201:105188. [PMID: 31545949 DOI: 10.1016/j.actatropica.2019.105188] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 11/15/2022]
Abstract
Triatoma petrocchiae is the newly member of the Triatoma brasiliensis species complex. This species overlaps with T. brasiliensis in geographic and ecotypic occupation in the sylvatic habitat because both inhabit rocky outcrops in the semi-arid portion of Brazilian northeast. In this region T. brasiliensis is the most important Chagas disease vector because it constantly colonizes domiciles. In contrast, T. petrocchiae is rarely found in peri or intradomiciliary habitats - reason why little is known about this species. Therefore, Here, we present information for the first time on. the T. petrocchiae ecotopes, genetic diversity, Trypanosoma cruzi prevalence/genotyping in comparison to T. brasiliensis. We found T. brasilensis (N = 223) and T. petrocchiae (N = 69) in co-habitation in rocky outcrops in three Districts of Paraíba and Rio Grande do Norte states. Forty-tree T. petrocchiae insects of eleven sampling spots (composing three geographic populations) were genotyped for the mitochondrial Cyt B gene and little geographic structure was observed. Tajima's D test suggested that species is evolving toward a mutation-drift equilibrium in our collection range. Sylvatic T. petrocchiae had 4% (3/68) of infected insects by T. cruzi, whereas T. brasiliensis had 26% (59/223). Fluorescent Fragment Length Barcoding demonstrated that all three T. petrocchiae harbored TcI whereas T. brasiliensis had TcI, but also TcIII, TcII/TcVI and T. rangeli genotype A, sometimes under mixed infections. None of infected T. petrocchiae were carrying mixed infections. However, this result should be confirmed using a larger pool of infected bugs. We here presented the first documentation of T. rangeli infecting T. brasiliensis. The finding of infected T. petrocchiae calls for constant vector monitoring because the epidemiologic scenario is dynamic and sylvatic vectors are progressively found in adaptation to anthropic environments.
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Affiliation(s)
- Tarcianne M Lima-Oliveira
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental, Universidade Federal da Paraíba-UFPB, Campus IV, Rio Tinto, Paraíba, 58297, Brazil; Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, São Paulo, 13083-862, Brazil
| | - Fernanda von Hertwig M Fontes
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, São Paulo, 13083-862, Brazil
| | - Maurício Lilioso
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, São Paulo, 13083-862, Brazil
| | - Dayane Pires-Silva
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, São Paulo, 13083-862, Brazil
| | - Marta Maria Geraldes Teixeira
- Laboratório de Taxonomia e Filogenia de Tripanossomatídeos, Instituto de Ciências Biomédicas, Universidade de São Paulo-USP, São Paulo, São Paulo, 05508-000, Brazil
| | - Jose Gabriel Vergara Meza
- Laboratório de Taxonomia e Filogenia de Tripanossomatídeos, Instituto de Ciências Biomédicas, Universidade de São Paulo-USP, São Paulo, São Paulo, 05508-000, Brazil
| | - Myriam Harry
- CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex 91190, France
| | - Jonathan Fileé
- CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex 91190, France
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz - Fiocruz, Rio de Janeiro, Rio de Janeiro, 21040-900, Brazil
| | - Carolina Valença-Barbosa
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, São Paulo, 13083-862, Brazil
| | - Elaine Folly-Ramos
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental, Universidade Federal da Paraíba-UFPB, Campus IV, Rio Tinto, Paraíba, 58297, Brazil
| | - Carlos Eduardo Almeida
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, São Paulo, 13083-862, Brazil.
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9
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Borsatto KC, Vilela Azeredo-Oliveira MT, Alevi KCC. Identification Key for the Chagas Disease Vectors of Five Brazilian States, Based on Cytogenetic Data. Am J Trop Med Hyg 2019; 100:303-305. [PMID: 30560768 DOI: 10.4269/ajtmh.18-0075] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Chagas disease is a public health problem caused by the protozoan Trypanosoma cruzi that affects about 8 million people worldwide. The main form of transmission of T. cruzi is vectorial, through triatomines feces contaminated with the parasite. All species are considered as potential vectors of T. cruzi. The main identification keys of these vectors are based only on morphological characters. However, there are very similar or even same species (cryptic species) that may lead to wrong classification of the vectors. Therefore, we developed an identification key using cytogenetic data, to aid and help the correct classification of triatomines. From the cytogenetic characters, identification keys were created for the five Brazilian states (Alagoas, Amapá, Ceará, Roraima, and Santa Catarina). These data are important because the correct classification of triatomines helps directly the activity of the vector control programs.
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Affiliation(s)
- Kelly Cristine Borsatto
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista "Júlio de Mesquita Filho", IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil
| | - Maria Tercília Vilela Azeredo-Oliveira
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista "Júlio de Mesquita Filho", IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil
| | - Kaio Cesar Chaboli Alevi
- Laboratório de Biologia Celular, Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista "Júlio de Mesquita Filho", IBILCE/UNESP, São José do Rio Preto, São Paulo, Brazil
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10
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Daflon-Teixeira NF, Coutinho C, Gomes TF, Toma HK, Duarte R, Bóia MN, Carvalho-Costa FA, Almeida CE, Lima MM. Multiple Approaches to Address Potential Risk Factors of Chagas Disease Transmission in Northeastern Brazil. Am J Trop Med Hyg 2019; 100:296-302. [PMID: 30734691 DOI: 10.4269/ajtmh.18-0480] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Chagas disease is one of the most significant systemic parasitosis in Latin America, caused by Trypanosoma cruzi, which is mainly transmitted by hematophagous insects, the triatomines. This research was carried out in both domestic and wild environments throughout a Northeastern rural locality. Triatomines were captured in both peridomicile and wild environments, obtaining 508 specimens of triatomines, of which 99.6% were Triatoma brasiliensis. Insects were captured in 10 (18.5%) peridomiciles with an average of 8.3 triatomines per residence. Triatoma brasiliensis nymphs and adults were found in six peridomiciles, generating a 11.1% colonization. No T. cruzi infection was detected in the 447 peridomestic insects analyzed. On the other hand, of the 55 sylvatic T. brasiliensis molecularly examined for T. cruzi, 12 (21%) were positive, all harboring T. cruzi I. The blood meal analysis by enzyme-linked immunosorbent assay from gut content revealed that both peridomestic and wild triatomine populations fed mainly on birds, refractory to the parasite, which may explain the null rate of natural infection prevalence in the domestic environment. However, infected triatomines for potential home infestation within the radius of insect dispersion capacity were registered in rock outcrops around the dwellings. Anthropogenic environmental influences are able to rapidly alter these scenarios. Therefore, to avoid disease transmission to humans, we recommend constant vector control combined with periodic serological surveillance. The associated methodology presented herein may serve as a model for early detections of risk factors for Chagas disease transmission in the Brazilian Northeast.
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Affiliation(s)
| | - Carolina Coutinho
- Instituto de Comunicação e Informação Científica e Tecnológica em Saúde/Fiocruz, Rio de Janeiro, Brazil
| | - Taís Ferreira Gomes
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz, IOC/Fiocruz, Rio de Janeiro, Brazil
| | - Helena Keiko Toma
- Laboratório de Diagnóstico Molecular e Hematologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Rosemere Duarte
- Departamento de Ciências Biológicas, Escola Nacional de Saúde Pública (ENSP)/Fiocruz, Rio de Janeiro, Brazil
| | - Márcio Neves Bóia
- Laboratório de Biologia e Parasitologia de Mamíferos Silvestres Reservatórios, IOC/Fiocruz, Rio de Janeiro, Brazil
| | - Filipe Anibal Carvalho-Costa
- Escritório Regional Fiocruz Piauí, Fundação Oswaldo Cruz, Teresina, Brazil.,Laboratório de Epidemiologia e Sistemática Molecular, IOC/Fiocruz, Rio de Janeiro, Brazil
| | | | - Marli Maria Lima
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz, IOC/Fiocruz, Rio de Janeiro, Brazil
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11
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Dale C, Almeida CE, endonça VJ, Oliveira J, da osa JA, Galvão C, Costa J. An updated and illustrated dichotomous key for the Chagas disease vectors of Triatomabrasiliensis species complex and their epidemiologic importance. Zookeys 2018; 805:33-43. [PMID: 30588153 PMCID: PMC6300697 DOI: 10.3897/zookeys.805.25559] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/04/2018] [Indexed: 12/02/2022] Open
Abstract
In the subfamily Triatominae, Triatoma exhibits the largest number of species, which are arranged in complexes. For the T.brasiliensis species complex, recent investigations based on results of geometric morphometrics combined with phylogeny have provided evidence that it should be composed of seven species: T.brasiliensis, T.bahiensis, T.juazeirensis, T.lenti, T.melanica, T.petrocchiae, and T.sherlocki, in which T.brasiliensis is divided in two subspecies: T.b.brasiliensis and T.b.macromelasoma. A taxonomic key is presented to identify each taxon. Among members of this complex, T.b.brasiliensis is the most important in an epidemiologic context, due to its high prevalence in natural infection by Trypanosomacruzi combined with a pronounced adaptation to domiciliary habitats. However, some members may be currently invading and colonizing homes, a process known as domiciliation. Therefore, the key presented here may be potentially useful for researchers as well as those involved in vector control measures.
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Affiliation(s)
- Carolina Dale
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz (IOC), FIOCRUZ, BrazilLaboratório de Biodiversidade Entomológica, Instituto Oswaldo CruzRio de JaneiroBrazil
| | - Carlos Eduardo Almeida
- Instituto de Biologia, Universidade Estadual de Campinas, UNICAMP, BrazilUniversidade Estadual de CampinasCamínasBrazil
| | - Vagner José endonça
- Universidade Federal do Piauí, UFPI, BrazilUniversidade Federal do PiauíPiauíBrazil
| | - Jader Oliveira
- Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, FCFAR/UNESP, BrazilUniversidade Estadual Paulista “Júlio de Mesquita Filho”São PauloBrazil
| | - João Aristeu da osa
- Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, FCFAR/UNESP, BrazilUniversidade Estadual Paulista “Júlio de Mesquita Filho”São PauloBrazil
| | - Cleber Galvão
- Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Instituto Oswaldo Cruz (IOC), FIOCRUZ, BrazilInstituto Oswaldo CruzRio de JaneiroBrazil
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz (IOC), FIOCRUZ, BrazilLaboratório de Biodiversidade Entomológica, Instituto Oswaldo CruzRio de JaneiroBrazil
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12
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Nakad Bechara CC, Londoño JC, Segovia M, Leon Sanchez MA, Martínez P CE, Rodríguez R MM, Carrasco HJ. Genetic variability of Panstrongylus geniculatus (Reduviidae: Triatominae) in the Metropolitan District of Caracas, Venezuela. INFECTION GENETICS AND EVOLUTION 2018; 66:236-244. [PMID: 30240833 DOI: 10.1016/j.meegid.2018.09.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/28/2018] [Accepted: 09/14/2018] [Indexed: 10/28/2022]
Abstract
Panstrongylus geniculatus has become the most frequently registered vector of Chagas disease in the metropolitan area of Caracas, Venezuela. This triatomine species has invaded urban areas in recent years and has been implicated in multiple oral outbreaks of Chagas disease in the region. The study of genetic variability and spatial structure in P. geniculatus populations can provide information about possible events of domiciliation and aid intervention programs against triatomine species rapidly adapting to urban ecotopes. We sequenced a region of the cytochrome-b gene in 114 specimens of P. geniculatus from the Metropolitan District of Caracas and assessed patterns of gene flow and phylogenetic relationships among these individuals. A total of 29 haplotypes were detected in the two sampled municipalities, Sucre and Libertador. Though high genetic connectivity was observed between the municipalities (FST = 0.10796; Nm = 11.20), subtle genetic structuring was also observed in particular geographic sub regions. Based on neutrality tests and the observed allele-frequency distribution, the Panstrongylus geniculatus population appears to be expanding and adapting to different microhabitats present in the study area. Our findings affirm the capacity of this insect to adapt to different environments and emphasize its principal role in the epidemiology of Chagas disease in northern Venezuela.
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Affiliation(s)
- Candy C Nakad Bechara
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela
| | - Juan Carlos Londoño
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela
| | - Maikell Segovia
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela
| | - Meyber A Leon Sanchez
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela
| | - Clara E Martínez P
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela
| | - Marlenes M Rodríguez R
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela
| | - Hernan Jose Carrasco
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Av. Los Ilustres, Los Chaguaramos, Caracas 1041, Venezuela.
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13
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Lilioso M, Folly-Ramos E, Rocha FL, Rabinovich J, Capdevielle-Dulac C, Harry M, Marcet PL, Costa J, Almeida CE. High Triatoma brasiliensis Densities and Trypanosoma cruzi Prevalence in Domestic and Peridomestic Habitats in the State of Rio Grande do Norte, Brazil: The Source for Chagas Disease Outbreaks? Am J Trop Med Hyg 2017; 96:1456-1459. [PMID: 28719275 DOI: 10.4269/ajtmh.16-0823] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
AbstractA total of 2,431 Triatoma brasiliensis were collected from 39 populations of Paraíba (PB) and Rio Grande do Norte (RN) states, Brazil. In PB, Trypanosoma cruzi infection was not detected in either peridomestic or domestic vector populations. In contrast, in RN, T. brasiliensis was detected with high parasite prevalence in these ecotopes (30.7-40.0%). Moreover, peridomicile insect population densities were more than double the average densities of all other settings evaluated (19.17 versus < 8.94 triatomine/man-hour). Genotyped parasites evidenced a mix of T. cruzi lineages circulating in both peridomestic and sylvatic populations. Although vector control efforts have dramatically decreased Chagas disease transmission to humans, recent outbreaks have been detected in four municipalities of RN state. Our results clearly evidence a worrisome proximity between infected vectors and humans in RN. Indeed, finding of infected T. brasiliensis inside homes is routinely recorded by local vector control surveillance staff around the outbreak area, challenging the current and conventional view that vector transmissions are controlled in northeastern Brazil. This scenario calls for strengthening vector control surveillance and interventions to prevent further Chagas transmission, especially in RN State.
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Affiliation(s)
- Mauricio Lilioso
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental (PPGEMA), Universidade Federal da Paraíba (UFPB), Joao Pessoa, Brazil
| | - Elaine Folly-Ramos
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental (PPGEMA), Universidade Federal da Paraíba (UFPB), Joao Pessoa, Brazil
| | - Fabiana Lopes Rocha
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental (PPGEMA), Universidade Federal da Paraíba (UFPB), Joao Pessoa, Brazil
| | - Jorge Rabinovich
- Centro de Estudios Parasitológicos y de Vectores (CEPAVE), Universidad Nacional de La Plata, La Plata, Argentina
| | - Claire Capdevielle-Dulac
- UMR Evolution, Génomes, Comportement, Ecologie, CNRS-IRD-Univ. Paris-Sud, Université Paris Saclay, Paris, France
| | - Myriam Harry
- UMR Evolution, Génomes, Comportement, Ecologie, CNRS-IRD-Univ. Paris-Sud, Université Paris Saclay, Paris, France
| | - Paula L Marcet
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia
| | - Jane Costa
- Laboratorio de Biodiversidade Entomologica, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Carlos Eduardo Almeida
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental (PPGEMA), Universidade Federal da Paraíba (UFPB), Joao Pessoa, Brazil.,Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
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14
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Oliveira J, Marcet PL, Takiya DM, Mendonça VJ, Belintani T, Bargues MD, Mateo L, Chagas V, Folly-Ramos E, Cordeiro-Estrela P, Gurgel-Gonçalves R, Costa J, da Rosa JA, Almeida CE. Combined phylogenetic and morphometric information to delimit and unify the Triatoma brasiliensis species complex and the Brasiliensis subcomplex. Acta Trop 2017; 170:140-148. [PMID: 28219669 DOI: 10.1016/j.actatropica.2017.02.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 02/03/2017] [Accepted: 02/13/2017] [Indexed: 11/16/2022]
Abstract
"Triatoma brasiliensis species complex" was defined as a monophyletic group of the species: T. brasiliensis, T. juazeirensis, T. melanica, and T. sherlocki. An alternative grouping scheme proposed the concept of "Brasiliensis subcomplex" which included the former species together with T. melanocephala, T. petrocchiae, T. lenti, T. tibiamaculata, and T. vitticeps. To evaluate the relationship among these taxa we combined the results obtained with four mitochondrial genes (12S, 16S, COI and Cytb, adding to 1811bp) and geometric morphometric analysis of wings and heads. Panstrongylus megistus was included in the analysis as it was previously found related to T. tibiamaculata, T. melanocephala and T. vitticeps. The results of both molecular and morphometric approaches clearly grouped the species analyzed into two monophyletic units, supported by both genetic and wing variability. The first one (G1) comprises the four species originally included in the T. brasiliensis species complex plus T. lenti and T. petrocchiae. The second group (G2) was composed by T. melanocephala, T. tibiamaculata and T. vitticeps, and remarkably, P. megistus if considering wing variability and phylogenetic results. Nevertheless, geometric morphometrics of heads provided a quantitative measurement that discriminates Panstrongylus from the Triatoma species based on the position of the antennal insertion relative to eyes, as it is used as the generic distinctive character. The discrepancy among approaches questions the validity of this character to define Panstrongylus genus. Independently of the chosen group definition -"T. brasiliensis species complex" or "Brasiliensis subcomplex"-we propose to delimit it to species of G1 that are all associated with the Caatinga biome in the Brazilian Northeast. G2 are the ones associated with the Atlantic Forest biome.
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Affiliation(s)
- Jader Oliveira
- Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, Brazil
| | - Paula L Marcet
- Division of Parasitic Diseases and Malaria, Centers for Diseases Control and Prevention, USA
| | | | | | - Tiago Belintani
- Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, Brazil
| | | | | | | | | | | | | | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz, FIOCRUZ, Brazil
| | - João A da Rosa
- Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, Brazil
| | - Carlos E Almeida
- Universidade Federal da Paraiba, Brazil; Universidade Estadual de Campinas, UNICAMP, Brazil.
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15
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Luna-Marín KP, Angulo-Silva VM, Hernández-Torres J, Ruiz-García M. Genetic Relationships and Spatial Genetic Structure Among Populations of Rhodnius prolixus (Hemiptera: Reduviidae) in Colombia and Venezuela Based on Mitochondrial Cytochrome-b Sequences. NEOTROPICAL ENTOMOLOGY 2017; 46:341-355. [PMID: 27889871 DOI: 10.1007/s13744-016-0470-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 11/15/2016] [Indexed: 06/06/2023]
Abstract
One hundred twenty Rhodnius prolixus (Stal) (Hemiptera: Reduviidae) specimens from 6 Colombian Departments and 1 Venezuelan State had 594-bp of the mitochondrial cytochrome-b gene sequenced to improve the understanding of evolutionary processes that shape the main vector of Chagas disease. The levels of genetic diversity for this species were low-medium with reference to other bugs. The genetic heterogeneity among the populations was very limited which means there has been extensive gene flow and/or very recent split processes. The overall sample as well as some individual populations showed evidence of recent population expansions (with the exception of Arauca, which yielded evidence of a bottleneck for a mismatch distribution). This expansion (11,000 or 2000-25,000 year ago depending of two procedures employed) coincides with the ending of the last intense glacial conditions during the Pleistocene and the beginning of the Holocene that had a warmer and wetter climate. Some of our autocorrelation analyses (AIDA and Genetic Landscape Interpolation Analysis) indicated local patches of high genetic similarity but no globally significant spatial structure. We did show an original haplotype distributed throughout the entirety of the geographical area studied.
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Affiliation(s)
- K P Luna-Marín
- Centro de Investigaciones en Enfermedades Tropicales (CINTROP), Univ Industrial de Santander (UIS), Bucaramanga, Colombia
- Lab de Genética de Poblaciones Molecular y Biología Evolutiva, Unidad de Genética, Depto de Biología, Facultad de Ciencias, Pontificia Univ Javeriana, Cra 7ª No 43-82, Bogotá, DC, Colombia
| | - V M Angulo-Silva
- Centro de Investigaciones en Enfermedades Tropicales (CINTROP), Univ Industrial de Santander (UIS), Bucaramanga, Colombia
| | - J Hernández-Torres
- Lab de Biología Molecular (CINBIN), Escuela de Biología, Univ Industrial de Santander (UIS), Bucaramanga, Colombia
| | - M Ruiz-García
- Lab de Genética de Poblaciones Molecular y Biología Evolutiva, Unidad de Genética, Depto de Biología, Facultad de Ciencias, Pontificia Univ Javeriana, Cra 7ª No 43-82, Bogotá, DC, Colombia.
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16
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Marchant A, Mougel F, Jacquin-Joly E, Costa J, Almeida CE, Harry M. Under-Expression of Chemosensory Genes in Domiciliary Bugs of the Chagas Disease Vector Triatoma brasiliensis. PLoS Negl Trop Dis 2016; 10:e0005067. [PMID: 27792774 PMCID: PMC5085048 DOI: 10.1371/journal.pntd.0005067] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 09/22/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND In Latin America, the bloodsucking bugs Triatominae are vectors of Trypanosoma cruzi, the parasite that causes Chagas disease. Chemical elimination programs have been launched to control Chagas disease vectors. However, the disease persists because native vectors from sylvatic habitats are able to (re)colonize houses-a process called domiciliation. Triatoma brasiliensis is one example. Because the chemosensory system allows insects to interact with their environment and plays a key role in insect adaption, we conducted a descriptive and comparative study of the chemosensory transcriptome of T. brasiliensis samples from different ecotopes. METHODOLOGY/PRINCIPAL FINDING In a reference transcriptome built using de novo assembly, we found transcripts encoding 27 odorant-binding proteins (OBPs), 17 chemosensory proteins (CSPs), 3 odorant receptors (ORs), 5 transient receptor potential channel (TRPs), 1 sensory neuron membrane protein (SNMPs), 25 takeout proteins, 72 cytochrome P450s, 5 gluthatione S-transferases, and 49 cuticular proteins. Using protein phylogenies, we showed that most of the OBPs and CSPs for T. brasiliensis had well supported orthologs in the kissing bug Rhodnius prolixus. We also showed a higher number of these genes within the bloodsucking bugs and more generally within all Hemipterans compared to the other species in the super-order Paraneoptera. Using both DESeq2 and EdgeR software, we performed differential expression analyses between samples of T. brasiliensis, taking into account their environment (sylvatic, peridomiciliary and domiciliary) and sex. We also searched clusters of co-expressed contigs using HTSCluster. Among differentially expressed (DE) contigs, most were under-expressed in the chemosensory organs of the domiciliary bugs compared to the other samples and in females compared to males. We clearly identified DE genes that play a role in the chemosensory system. CONCLUSION/SIGNIFICANCE Chemosensory genes could be good candidates for genes that contribute to adaptation or plastic rearrangement to an anthropogenic system. The domiciliary environment probably includes less diversity of xenobiotics and probably has more stable abiotic parameters than do sylvatic and peridomiciliary environments. This could explain why both detoxification and cuticle protein genes are less expressed in domiciliary bugs. Understanding the molecular basis for how vectors adapt to human dwellings may reveal new tools to control disease vectors; for example, by disrupting chemical communication.
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Affiliation(s)
- Axelle Marchant
- UMR Evolution, Génomes, Comportement, Ecologie, CNRS-IRD- Univ. Paris-Sud, Université Paris Saclay, Campus CNRS, Gif-sur-Yvette – France
- UFR Sciences, Université Paris Sud, Orsay, France
| | - Florence Mougel
- UMR Evolution, Génomes, Comportement, Ecologie, CNRS-IRD- Univ. Paris-Sud, Université Paris Saclay, Campus CNRS, Gif-sur-Yvette – France
- UFR Sciences, Université Paris Sud, Orsay, France
| | - Emmanuelle Jacquin-Joly
- INRA, UMR 1392, Institut d’Ecologie et des Sciences de l’Environnement de Paris, Route de Saint Cyr, Versailles, France
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica; Instituto Oswaldo Cruz - Fiocruz; Rio de Janeiro; Brasil Instituto Oswaldo Cruz, Fiocruz – Brazil
| | - Carlos Eduardo Almeida
- Universidade Estadual de Campinas (Uncamp), Campinas São Paulo – Brazil
- Universidade Federal da Paraíba (UFPB), Paraíba – Brazil
| | - Myriam Harry
- UMR Evolution, Génomes, Comportement, Ecologie, CNRS-IRD- Univ. Paris-Sud, Université Paris Saclay, Campus CNRS, Gif-sur-Yvette – France
- UFR Sciences, Université Paris Sud, Orsay, France
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17
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Monsalve Y, Panzera F, Herrera L, Triana-Chávez O, Gómez-Palacio A. Population differentiation of the Chagas disease vector Triatoma maculata (Erichson, 1848) from Colombia and Venezuela. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2016; 41:72-79. [PMID: 27232127 DOI: 10.1111/jvec.12196] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 11/26/2016] [Indexed: 06/05/2023]
Abstract
The emerging vector of Chagas disease, Triatoma maculata (Hemiptera, Reduviidae), is one of the most widely distributed Triatoma species in northern South America. Despite its increasing relevance as a vector, no consistent picture of the magnitude of genetic and phenetic diversity has yet been developed. Here, several populations of T. maculata from eleven Colombia and Venezuela localities were analyzed based on the morphometry of wings and the mitochondrial NADH dehydrogenase subunit 4 (ND4) gene sequences. Our results showed clear morphometric and genetic differences among Colombian and Venezuelan populations, indicating high intraspecific diversity. Inter-population divergence is suggested related to East Cordillera in Colombia. Analyses of other populations from Colombia, Venezuela, and Brazil from distinct eco-geographic regions are still needed to understand its systematics and phylogeography as well as its actual role as a vector of Chagas disease.
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Affiliation(s)
- Yoman Monsalve
- Grupo Grupo de Biología y Control de Enfermedades Infecciosas - BCEI, Universidad de Antioquia UdeA, Medellín, Antioquia, Colombia
| | - Francisco Panzera
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Leidi Herrera
- Instituto de Zoología y Ecologia Tropical, Universidad Central de Venezuela, Caracas, Venezuela
| | - Omar Triana-Chávez
- Grupo Grupo de Biología y Control de Enfermedades Infecciosas - BCEI, Universidad de Antioquia UdeA, Medellín, Antioquia, Colombia
| | - Andrés Gómez-Palacio
- Grupo Grupo de Biología y Control de Enfermedades Infecciosas - BCEI, Universidad de Antioquia UdeA, Medellín, Antioquia, Colombia.
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Pessoa GCD, de Sousa TN, Sonoda IV, Diotaiuti L. Assessing the mitochondrial DNA diversity of the Chagas disease vector Triatoma sordida (Hemiptera: Reduviidae). Mem Inst Oswaldo Cruz 2016; 111:322-9. [PMID: 27143491 PMCID: PMC4878301 DOI: 10.1590/0074-02760150429] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 03/17/2016] [Indexed: 11/22/2022] Open
Abstract
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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Affiliation(s)
- Grasielle Caldas D‘Ávila Pessoa
- Fundação Oswaldo Cruz, Centro de Pesquisas René Rachou, Laboratório de
Referência em Triatomíneos e Epidemiologia da Doença de Chagas, Belo Horizonte, MG,
Brasil
| | - Tais Nóbrega de Sousa
- Fundação Oswaldo Cruz, Centro de Pesquisas René Rachou, Laboratório de
Malária, Belo Horizonte, MG, Brasil
| | - Ivan Vieira Sonoda
- Fundação Oswaldo Cruz, Centro de Pesquisas René Rachou, Laboratório de
Referência em Triatomíneos e Epidemiologia da Doença de Chagas, Belo Horizonte, MG,
Brasil
| | - Liléia Diotaiuti
- Fundação Oswaldo Cruz, Centro de Pesquisas René Rachou, Laboratório de
Referência em Triatomíneos e Epidemiologia da Doença de Chagas, Belo Horizonte, MG,
Brasil
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Almeida CE, Faucher L, Lavina M, Costa J, Harry M. Molecular Individual-Based Approach on Triatoma brasiliensis: Inferences on Triatomine Foci, Trypanosoma cruzi Natural Infection Prevalence, Parasite Diversity and Feeding Sources. PLoS Negl Trop Dis 2016; 10:e0004447. [PMID: 26891047 PMCID: PMC4758651 DOI: 10.1371/journal.pntd.0004447] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 01/20/2016] [Indexed: 11/19/2022] Open
Abstract
We used an individual-based molecular multisource approach to assess the epidemiological importance of Triatoma brasiliensis collected in distinct sites and ecotopes in Rio Grande do Norte State, Brazil. In the semi-arid zones of Brazil, this blood sucking bug is the most important vector of Trypanosoma cruzi--the parasite that causes Chagas disease. First, cytochrome b (cytb) and microsatellite markers were used for inferences on the genetic structure of five populations (108 bugs). Second, we determined the natural T. cruzi infection prevalence and parasite diversity in 126 bugs by amplifying a mini-exon gene from triatomine gut contents. Third, we identified the natural feeding sources of 60 T. brasiliensis by using the blood meal content via vertebrate cytb analysis. Demographic inferences based on cytb variation indicated expansion events in some sylvatic and domiciliary populations. Microsatellite results indicated gene flow between sylvatic and anthropic (domiciliary and peridomiciliary) populations, which threatens vector control efforts because sylvatic population are uncontrollable. A high natural T. cruzi infection prevalence (52-71%) and two parasite lineages were found for the sylvatic foci, in which 68% of bugs had fed on Kerodon rupestris (Rodentia: Caviidae), highlighting it as a potential reservoir. For peridomiciliary bugs, Galea spixii (Rodentia: Caviidae) was the main mammal feeding source, which may reinforce previous concerns about the potential of this animal to link the sylvatic and domiciliary T. cruzi cycles.
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Affiliation(s)
- Carlos Eduardo Almeida
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas (UNESP), Araraquara, SP, Brasil
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental – PPGEMA, Universidade Federal da Paraíba, PB, Brasil
| | - Leslie Faucher
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Morgane Lavina
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz – Fiocruz, Rio de Janeiro, RJ, Brasil
| | - Myriam Harry
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
- Université Paris-Sud, Orsay, France
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20
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Barbosa-Silva AN, Câmara ACJD, Martins K, Nunes DF, Oliveira PICD, Azevedo PRMD, Chiari E, Galvão LMDC. Characteristics of Triatomine infestation and natural Trypanosoma cruzi infection in the State of Rio Grande do Norte, Brazil. Rev Soc Bras Med Trop 2016; 49:57-67. [DOI: 10.1590/0037-8682-0300-2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Affiliation(s)
| | | | - Kiev Martins
- Universidade Federal do Rio Grande do Norte, Brazil
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21
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Costa J, Bargues MD, Neiva VL, Lawrence GG, Gumiel M, Oliveira G, Cabello P, Lima MM, Dotson E, Provance DW, Almeida CE, Mateo L, Mas-Coma S, Dujardin JP. Phenotypic variability confirmed by nuclear ribosomal DNA suggests a possible natural hybrid zone of Triatoma brasiliensis species complex. INFECTION GENETICS AND EVOLUTION 2015; 37:77-87. [PMID: 26520796 DOI: 10.1016/j.meegid.2015.10.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 10/07/2015] [Accepted: 10/24/2015] [Indexed: 11/16/2022]
Abstract
Triatoma brasiliensis macromelasoma occurs in Pernambuco state, Brazil, which is situated between the distribution areas of Triatoma brasiliensis brasiliensis (north) and Triatoma juazeirensis (south). T. b. macromelasoma displays greater variations in its chromatic phenotype than either T. b. brasiliensis or T. juazeirensis, and patterns reminiscent of one or the other. Experimental crosses from each of these members of the T. brasiliensis species complex generated fertile offspring suggesting that viable hybrids could be present in nature, despite their significant genetic distances. Considering the geographical position of occurrence of the T. b. macromelasoma (in Pernambuco) it was proposed to be an area capable of supporting natural hybridization between T. b. brasiliensis and T. juazeirensis. Since phenotypic variability is expected, this study investigated the existence of intermediate chromatic phenotypes for T. b. macromelasoma in various locations in areas between the T. b. brasiliensis and T. juazeirensis occurrences. Thirteen different color patterns were for the first time characterized and nine of those displayed intermediate phenotypes. Molecular analysis performed using ribosomal DNA intergenic region, grouped all within the T. brasiliensis complex. The intermediate chromatic phenotypes, molecular analysis and experimental crosses all support the distinction of a zone of hybridization that gave rise to the T. b. macromelasoma through homoploidal evolution.
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Affiliation(s)
- Jane Costa
- Laboratório de Biodiversidade Entomológica,Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
| | - Maria Dolores Bargues
- Dep. de Parasitología, Facultad de Farmacia, Univ. de Valencia, Burjassot, Valencia, Spain
| | - Vanessa Lima Neiva
- Laboratório de Biodiversidade Entomológica,Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Gena G Lawrence
- Entomology Branch, Div. Parasitic Diseases, CDC, Atlanta, GA, USA
| | - Marcia Gumiel
- Laboratório de Fisiologia e Bioquímica de Insetos Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | | | - Pedro Cabello
- Laboratório de Genética Humana, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Marli Maria Lima
- Laboratório de Eco-epidemiologia da Doença de Chagas, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Ellen Dotson
- Entomology Branch, Div. Parasitic Diseases, CDC, Atlanta, GA, USA
| | | | - Carlos Eduardo Almeida
- Univers. Est. Paulista Júlio de Mesquita Filho, Araquara, SP, Prog. de Pós-Graduação em Ecologia e Monitoramento Ambiental (PPGEMA), UFPB, Campus IV, Paraíba, Brazil.
| | - Lucia Mateo
- Dep. de Parasitología, Facultad de Farmacia, Univ. de Valencia, Burjassot, Valencia, Spain
| | - Santiago Mas-Coma
- Dep. de Parasitología, Facultad de Farmacia, Univ. de Valencia, Burjassot, Valencia, Spain
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22
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Ribeiro AR, Mendonça VJ, Alves RT, Martinez I, Araújo RFD, Mello F, da Rosa JA. Trypanosoma cruzi strains from triatomine collected in Bahia and Rio Grande do Sul, Brazil. Rev Saude Publica 2015; 48:295-302. [PMID: 24897051 PMCID: PMC4206147 DOI: 10.1590/s0034-8910.2014048004719] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 07/11/2013] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE Collection of triatomines in domestic, peridomestic and sylvatic environments
in states of Bahia and Rio Grande do Sul, Northeastern and Southern Brazil
respectively, and isolation of Trypanosoma cruzi
strains. METHODS First, the captured triatomines were identified using insect identification
keys, then their intestinal content was examined by abdominal compression,
and the samples containing trypanosomatid forms were inoculated in LIT
medium and Swiss mice. RESULTS Six triatomine species were collected in cities in Bahia, namely
Panstrongylus geniculatus (01), Triatoma
melanocephala (11), T. lenti (94), T.
pseudomaculata (02), T. sherlocki (26) and
T. sordida (460), and two in cities in Rio Grande do
Sul, namely T. circummaculata (11) and T.
rubrovaria (115). Out of the specimens examined, T.
cruzi was isolated from 28 triatomine divided into four
different species: T. melanocephala (one), T.
lenti (one), T. rubrovaria (16) and T.
sordida (10). Their index of natural infection by T.
cruzi was 6.4%. CONCLUSIONS The isolation of T. cruzi strains from triatomines found in
domestic and peridomestic areas shows the potential risk of transmission of
Chagas disease in the studied cities. The maintenance of those T.
cruzi strains in laboratory is intended to promote studies that
facilitate the understanding of the parasite-vector-host relationship.
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Affiliation(s)
- Aline Rimoldi Ribeiro
- Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - Vagner José Mendonça
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Júlio de Mesquita Filho, Araraquara, SP, Brasil
| | - Renata Tomé Alves
- Departamento de Análises Clínicas Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | - Isabel Martinez
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Júlio de Mesquita Filho, Araraquara, SP, Brasil
| | | | - Fernanda Mello
- Secretaria de Saúde do Estado do Rio Grande do Sul, Porto Alegre, RS, Brasil
| | - João Aristeu da Rosa
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Júlio de Mesquita Filho, Araraquara, SP, Brasil
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23
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Marchant A, Mougel F, Almeida C, Jacquin-Joly E, Costa J, Harry M. De novo transcriptome assembly for a non-model species, the blood-sucking bug Triatoma brasiliensis, a vector of Chagas disease. Genetica 2014; 143:225-39. [PMID: 25233990 DOI: 10.1007/s10709-014-9790-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 09/01/2014] [Indexed: 11/29/2022]
Abstract
High throughput sequencing (HTS) provides new research opportunities for work on non-model organisms, such as differential expression studies between populations exposed to different environmental conditions. However, such transcriptomic studies first require the production of a reference assembly. The choice of sampling procedure, sequencing strategy and assembly workflow is crucial. To develop a reliable reference transcriptome for Triatoma brasiliensis, the major Chagas disease vector in Northeastern Brazil, different de novo assembly protocols were generated using various datasets and software. Both 454 and Illumina sequencing technologies were applied on RNA extracted from antennae and mouthparts from single or pooled individuals. The 454 library yielded 278 Mb. Fifteen Illumina libraries were constructed and yielded nearly 360 million RNA-seq single reads and 46 million RNA-seq paired-end reads for nearly 45 Gb. For the 454 reads, we used three assemblers, Newbler, CAP3 and/or MIRA and for the Illumina reads, the Trinity assembler. Ten assembly workflows were compared using these programs separately or in combination. To compare the assemblies obtained, quantitative and qualitative criteria were used, including contig length, N50, contig number and the percentage of chimeric contigs. Completeness of the assemblies was estimated using the CEGMA pipeline. The best assembly (57,657 contigs, completeness of 80 %, <1 % chimeric contigs) was a hybrid assembly leading to recommend the use of (1) a single individual with large representation of biological tissues, (2) merging both long reads and short paired-end Illumina reads, (3) several assemblers in order to combine the specific advantages of each.
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Affiliation(s)
- A Marchant
- Laboratoire Evolution, Génomes et Spéciation LEGS, UPR 9034, CNRS, Avenue de la Terrasse, Bâtiment 13, BP1, 91198, Gif-sur-Yvette, France,
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24
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Rebaudo F, Costa J, Almeida CE, Silvain JF, Harry M, Dangles O. Simulating population genetics of pathogen vectors in changing landscapes: guidelines and application with Triatoma brasiliensis. PLoS Negl Trop Dis 2014; 8:e3068. [PMID: 25102068 PMCID: PMC4125301 DOI: 10.1371/journal.pntd.0003068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/21/2014] [Indexed: 11/28/2022] Open
Abstract
Background Understanding the mechanisms that influence the population dynamics and spatial genetic structure of the vectors of pathogens infecting humans is a central issue in tropical epidemiology. In view of the rapid changes in the features of landscape pathogen vectors live in, this issue requires new methods that consider both natural and human systems and their interactions. In this context, individual-based model (IBM) simulations represent powerful yet poorly developed approaches to explore the response of pathogen vectors in heterogeneous social-ecological systems, especially when field experiments cannot be performed. Methodology/Principal Findings We first present guidelines for the use of a spatially explicit IBM, to simulate population genetics of pathogen vectors in changing landscapes. We then applied our model with Triatoma brasiliensis, originally restricted to sylvatic habitats and now found in peridomestic and domestic habitats, posing as the most important Trypanosoma cruzi vector in Northeastern Brazil. We focused on the effects of vector migration rate, maximum dispersal distance and attraction by domestic habitat on T. brasiliensis population dynamics and spatial genetic structure. Optimized for T. brasiliensis using field data pairwise fixation index (FST) from microsatellite loci, our simulations confirmed the importance of these three variables to understand vector genetic structure at the landscape level. We then ran prospective scenarios accounting for land-use change (deforestation and urbanization), which revealed that human-induced land-use change favored higher genetic diversity among sampling points. Conclusions/Significance Our work shows that mechanistic models may be useful tools to link observed patterns with processes involved in the population genetics of tropical pathogen vectors in heterogeneous social-ecological landscapes. Our hope is that our study may provide a testable and applicable modeling framework to a broad community of epidemiologists for formulating scenarios of landscape change consequences on vector dynamics, with potential implications for their surveillance and control. Worldwide, humans are modifying landscapes at an unprecedented rate. These modifications have an influence on the ecology of pathogen vectors, yet this issue has received relatively little input from modeling research. The current study presents guidelines for the use of a modeling framework for the representation of the dynamics and spatial genetic structure of pathogen vectors. It allows considering spatiotemporal landscape modifications explicitly, to represent human-altered modifications and consequences. We applied this modeling framework to Triatoma brasiliensis, vector of the pathogen Trypanosoma cruzi responsible for the Chagas disease, in the semi-arid Northeastern Brazil. Using field data of pairwise fixation index (FST) from microsatellite loci, we found that migration rate, maximum dispersal distance and attraction by domestic habitat were all key parameters to understand vector spatial genetic structure at the landscape level. At the interface across disciplines, this study provides to the community of epidemiologists a testable and applicable framework to foresee landscape modification consequences on vector dynamics and genetic structure, with potential implications for their surveillance and control.
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Affiliation(s)
- Francois Rebaudo
- BEI-UR072, IRD, Gif-sur-Yvette, France
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
- * E-mail:
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz - Fiocruz, Rio de Janeiro, Rio de Janeiro, Brasil
| | - Carlos E. Almeida
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, UNESP, Araraquara, Sao Paolo, Brasil
| | - Jean-Francois Silvain
- BEI-UR072, IRD, Gif-sur-Yvette, France
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
| | - Myriam Harry
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
| | - Olivier Dangles
- BEI-UR072, IRD, Gif-sur-Yvette, France
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
- Instituto de Ecología, Campus Cotacota, Universidad Mayor San Andrés, La Paz, Bolivia
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Valença-Barbosa C, Lima MM, Sarquis O, Bezerra CM, Abad-Franch F. A common Caatinga cactus, Pilosocereus gounellei, is an important ecotope of wild Triatoma brasiliensis populations in the Jaguaribe valley of northeastern Brazil. Am J Trop Med Hyg 2014; 90:1059-62. [PMID: 24710611 DOI: 10.4269/ajtmh.13-0204] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Triatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops. However, this species frequently infests/re-infests houses in rock-free sedimentary lowlands. We therefore hypothesized that it should also occupy other natural ecotopes. We show that a common Caatinga cactus, Pilosocereus gounellei, locally known as xiquexique, often harbors T. brasiliensis breeding colonies apparently associated with rodents (n = 44 cacti, infestation rate = 47.7%, 157 bugs captured). Our findings suggest that infested cacti might be involved in house re-infestation by T. brasiliensis in the Caatinga region.
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Affiliation(s)
- Carolina Valença-Barbosa
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil; Secretaria Estadual de Saúde do Ceará, Fortaleza, Brazil; Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brazil
| | - Marli M Lima
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil; Secretaria Estadual de Saúde do Ceará, Fortaleza, Brazil; Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brazil
| | - Otília Sarquis
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil; Secretaria Estadual de Saúde do Ceará, Fortaleza, Brazil; Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brazil
| | - Claudia M Bezerra
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil; Secretaria Estadual de Saúde do Ceará, Fortaleza, Brazil; Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brazil
| | - Fernando Abad-Franch
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil; Secretaria Estadual de Saúde do Ceará, Fortaleza, Brazil; Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brazil
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26
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Mitochondrial PCR-RFLP Assay to Distinguish Triatoma brasiliensis macromelasoma from Triatoma brasiliensis brasiliensis Subspecies (Hemiptera: Reduviidae). J Trop Med 2014; 2013:305198. [PMID: 24454408 PMCID: PMC3877644 DOI: 10.1155/2013/305198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 11/05/2013] [Indexed: 11/29/2022] Open
Abstract
Triatoma brasiliensis sensu lato (s.l.), the main vector of Chagas disease in northeastern Brazil, is a species complex comprising four species, one with two subspecies (T. brasiliensis brasiliensis, T. brasiliensis macromelasoma, T. juazeirensis, T. sherlocki, and T. melanica), and each taxon displaying distinct ecological requirements. In order to evaluate the genetic relationships among nine T. brasiliensis s.l. populations from northeastern Brazil, we analyzed their mitochondrial cytochrome c oxidase subunit 1 sequences and suggested a PCR-RFLP assay to distinguish between T. b. macromelasoma and T. b. brasiliensis subspecies. All the specimens were morphologically identified as T. b. brasiliensis. The resulting phylogenies identified two major clades that are congruent with the geographical populations studied. Based on collection sites and in accordance with type-location, one clade was identified as the subspecies T. b. macromelasoma. The second clade grouped T. b. brasiliensis populations. Restriction endonuclease sites were observed in the sequences and used in PCR-RFLP assays, producing distinct fingerprints for T. b. macromelasoma and T. b. brasiliensis populations. The results suggest that these are different species and that gene flow occurs only among T. b. brasiliensis populations, possibly associated with human activity in the area.
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27
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Coutinho CF, Souza-Santos R, Lima MM. Combining geospatial analysis and exploratory study of triatomine ecology to evaluate the risk of Chagas disease in a rural locality. Acta Trop 2012; 121:30-3. [PMID: 22015423 DOI: 10.1016/j.actatropica.2011.10.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 09/20/2011] [Accepted: 10/06/2011] [Indexed: 10/16/2022]
Abstract
The use of geo-spatial analysis to anticipate transmission risk for Chagas disease was tested in a rural area of northeast Brazil in an approach that combined geo-referencing and exploratory study of triatomine infestation, including related elements such as the environment and hosts. A total of 617 triatomine specimens, mainly Triatoma brasiliensis, were captured, exhibiting an overall T. cruzi positivity of 44.4%. Layer analysis indicated that the greatest transmission risk to man was associated with woodpiles. The buffer area generated contained uninhabited dwellings teeming with bats and positive bugs. Other locations outside the buffer, near uninhabited dwellings housing cattle, contained colonies of triatomines harboring T. cruzi. The results indicate that local residents' activities themselves favor the development of risk areas for Chagas disease.
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28
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Genetics and evolution of triatomines: from phylogeny to vector control. Heredity (Edinb) 2011; 108:190-202. [PMID: 21897436 DOI: 10.1038/hdy.2011.71] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Triatomines are hemipteran bugs acting as vectors of the protozoan parasite Trypanosoma cruzi. This parasite causes Chagas disease, one of the major parasitic diseases in the Americas. Studies of triatomine genetics and evolution have been particularly useful in the design of rational vector control strategies, and are reviewed here. The phylogeography of several triatomine species is now slowly emerging, and the struggle to reconcile the phenotypic, phylogenetic, ecological and epidemiological species concepts makes for a very dynamic field. Population genetic studies using different markers indicate a wide range of population structures, depending on the triatomine species, ranging from highly fragmented to mobile, interbreeding populations. Triatomines transmit T. cruzi in the context of complex interactions between the insect vectors, their bacterial symbionts and the parasites; however, an integrated view of the significance of these interactions in triatomine biology, evolution and in disease transmission is still lacking. The development of novel genetic markers, together with the ongoing sequencing of the Rhodnius prolixus genome and more integrative studies, will provide key tools to expanding our understanding of these important insect vectors and allow the design of improved vector control strategies.
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29
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Sarquis O, Oliveira LS, Rego R, Gonçalves JM, Lima MM, Maciel-de-Freitas R. Evaluation of RbCl and CrCl₃ as markers of Triatoma brasiliensis (Hemiptera: Reduviidae) nymphs: persistence and influence of Rb and Cr on triatomine biology. Mem Inst Oswaldo Cruz 2011; 106:385-9. [PMID: 21739023 DOI: 10.1590/s0074-02762011000400001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Accepted: 12/16/2010] [Indexed: 11/22/2022] Open
Abstract
In order to mark Triatoma brasiliensis, the vector of Chagas disease in Brazil, two chemical compounds, rubidium chloride (RbCl) and chromium chloride (CrCl₃), were tested. First, 199 N2-N5 nymphs were fed on blood with 0.025M RbCl. Rb marker positivity ranged from 2.5% (N3)-70% (N2), with a maximum persistence of 98 days. Second, 265 N2-N5 nymphs were fed on blood containing 0.0015M CrCl₃. Cr marker positivity ranged up to 93% (N5), with a maximum persistence of 119 days. Finally, we blood fed 213 T. brasiliensis to investigate whether CrCl₃ altered the biology of this insect. The developmental time of T. brasiliensis was unaltered, but the survival of the Cr-marked group was lower than that of the control group. Differences in the mean fecundity of the control (mean of 156.1) and experimental (mean of 135.6) groups were not statistically significant and 100% of the egg batches of females Cr-marked as nymphs were positive. In conclusion, CrCl₃ is a useful tool for marking T. brasiliensis nymphs due to its high positivity and persistence.
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Affiliation(s)
- Otília Sarquis
- Laboratório de Transmissores de Hematozoários, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brasil
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High genetic diversity in a single population of Triatoma sanguisuga (LeConte, 1855) inferred from two mitochondrial markers: Cytochrome b and 16S ribosomal DNA. INFECTION GENETICS AND EVOLUTION 2011; 11:671-7. [DOI: 10.1016/j.meegid.2011.02.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 02/08/2011] [Accepted: 02/09/2011] [Indexed: 11/22/2022]
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Sarquis O, Carvalho-Costa FA, Oliveira LS, Duarte R, D Andrea PS, de Oliveira TG, Lima MM. Ecology of Triatoma brasiliensis in northeastern Brazil: seasonal distribution, feeding resources, and Trypanosoma cruzi infection in a sylvatic population. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2010; 35:385-394. [PMID: 21175946 DOI: 10.1111/j.1948-7134.2010.00097.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We assessed some ecological parameters of Triatoma brasiliensis in rock piles in the state of Ceará during the rainy and dry seasons. The greatest density was in April (median = 12.5 triatomines/site). The greatest abundance was in December, when the insects were more dispersed and the density per site was lower (6 triatomines/site). The nutritional status of females and 5th instar nymphs was increased in July. The rate of T. cruzi infection reached its highest peak in July (10.9%). ELISA revealed that the principal food sources were birds (33.1%), followed by armadillos (18.8%). Food sources were more frequently identified during the rainy season. T. brasiliensis specimens collected in the drought tended to: i) present lower rates of T. cruzi infection and gut content reactivity to tested antisera, ii) have a poorer nutritional status, iii) exhibit lower fecundity, iv) be more dispersed among the studied collection sites, and v) be more abundant and easily collected in the surface of the rocks, possibly reflecting an increased searching for blood meals. Such findings underscore epidemiological concerns and allow inferences about the season when triatomines can more frequently invade the peridomestic environment in search of food and recolonize artificial structures.
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Affiliation(s)
- Otilia Sarquis
- Laboratório de Eco-Epidemiologia da Doença de Chagas, Instituto Oswaldo Cruz (IOC/Fiocruz), Rio de Janeiro, RJ, Brazil
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Almeida CE, Folly-Ramos E, Peterson AT, Lima-Neiva V, Gumiel M, Duarte R, Lima MM, Locks M, Beltrão M, Costa J. Could the bug Triatoma sherlocki be vectoring Chagas disease in small mining communities in Bahia, Brazil? MEDICAL AND VETERINARY ENTOMOLOGY 2009; 23:410-417. [PMID: 19941607 DOI: 10.1111/j.1365-2915.2009.00822.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Searches for Chagas disease vectors were performed at the type locality from which Triatoma sherlocki Papa et al. (Hemiptera: Reduviidae: Triatominae) was described in the municipality of Gentio do Ouro, in the state of Bahia, Brazil, and in a small artisan quarry-mining community approximately 13 km distant in a remote area of the same municipality. The latter site represents a new locality record for this species. Adults, nymphs and exuviae of T. sherlocki were found in 21% of human dwellings, indicating that the species is in the process of domiciliation. Prevalence of Trypanosoma cruzi infection in collected bugs was 10.8%. Simple predictive approaches based on environmental similarity were used to identify additional sites likely suitable for this species. The approach successfully predicted an additional five sites for the species in surrounding landscapes. Ecological and entomological indicators were combined to discuss whether this scenario likely represents an isolated case or an emerging public health problem.
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Affiliation(s)
- C E Almeida
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz/FIOCRUZ (IOC/Fiocruz), Rio de Janeiro, Brazil.
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33
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Almeida CE, Marcet PL, Gumiel M, Takiya DM, Cardozo-de-Almeida M, Pacheco RS, Lopes CM, Dotson EM, Costa J. Phylogenetic and phenotypic relationships among Triatoma carcavalloi (Hemiptera: Reduviidae: Triatominae) and related species collected in domiciles in Rio Grande do Sul State, Brazil. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2009; 34:164-173. [PMID: 20836820 DOI: 10.1111/j.1948-7134.2009.00023.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Triatoma carcavalloi is considered a rare Chagas disease vector often collected inside domiciles in Rio Grande do Sul State. In this Brazilian state, T. carcavalloi has been collected in the same ecotope (rock piles) with two other species (T. rubrovaria and T. circummaculata), with which it also shares morphological characteristics. Previous morphological studies placed T. carcavalloi in the same species complex ("infestans complex") and subcomplex ("rubrovaria subcomplex") as T. rubrovaria, whereas T. circummaculata was placed in the "circummaculata complex." The phylogeny of a group composed of 16 species of triatomines was reevaluated with the inclusion of T. carcavalloi by Bayesian analysis using mtDNA sequences of subunits 12S and 16S of the ribosomal RNA, and the cytochrome oxidase I (COI) genes. The phenotypic relationship among T. carcavalloi and related triatomines was also inferred from morphometrics. Phylogenetic results indicate that T. carcavalloi is a sister species of T. rubrovaria, and both were recovered as closely related to T. circummaculata. Morphometric studies confirmed the closeness among T. carcavalloi, T. rubrovaria, and T. circummaculata, prompting the placement of the latter species in the "infestans complex" and "rubrovaria subcomplex."
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Affiliation(s)
- Carlos Eduardo Almeida
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz IOC/Fiocruz, Av Brasil 4365, 21045-900 Rio de Janeiro, Brazil
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Costa J, Lorenzo M. Biology, diversity and strategies for the monitoring and control of triatomines - Chagas disease vectors. Mem Inst Oswaldo Cruz 2009; 104 Suppl 1:46-51. [DOI: 10.1590/s0074-02762009000900008] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2009] [Accepted: 06/10/2009] [Indexed: 11/22/2022] Open
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Dorn PL, Calderon C, Melgar S, Moguel B, Solorzano E, Dumonteil E, Rodas A, de la Rua N, Garnica R, Monroy C. Two distinct Triatoma dimidiata (Latreille, 1811) taxa are found in sympatry in Guatemala and Mexico. PLoS Negl Trop Dis 2009; 3:e393. [PMID: 19274073 PMCID: PMC2648038 DOI: 10.1371/journal.pntd.0000393] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Accepted: 02/11/2009] [Indexed: 11/19/2022] Open
Abstract
Approximately 10 million people are infected with Trypanosoma cruzi, the causative agent of Chagas disease, which remains the most serious parasitic disease in the Americas. Most people are infected via triatomine vectors. Transmission has been largely halted in South America in areas with predominantly domestic vectors. However, one of the main Chagas vectors in Mesoamerica, Triatoma dimidiata, poses special challenges to control due to its diversity across its large geographic range (from Mexico into northern South America), and peridomestic and sylvatic populations that repopulate houses following pesticide treatment. Recent evidence suggests T. dimidiata may be a complex of species, perhaps including cryptic species; taxonomic ambiguity which confounds control. The nuclear sequence of the internal transcribed spacer 2 (ITS2) of the ribosomal DNA and the mitochondrial cytochrome b (mt cyt b) gene were used to analyze the taxonomy of T. dimidiata from southern Mexico throughout Central America. ITS2 sequence divides T. dimidiata into four taxa. The first three are found mostly localized to specific geographic regions with some overlap: (1) southern Mexico and Guatemala (Group 2); (2) Guatemala, Honduras, El Salvador, Nicaragua, and Costa Rica (Group 1A); (3) and Panama (Group 1B). We extend ITS2 Group 1A south into Costa Rica, Group 2 into southern Guatemala and show the first information on isolates in Belize, identifying Groups 2 and 3 in that country. The fourth group (Group 3), a potential cryptic species, is dispersed across parts of Mexico, Guatemala, and Belize. We show it exists in sympatry with other groups in Peten, Guatemala, and Yucatan, Mexico. Mitochondrial cyt b data supports this putative cryptic species in sympatry with others. However, unlike the clear distinction of the remaining groups by ITS2, the remaining groups are not separated by mt cyt b. This work contributes to an understanding of the taxonomy and population subdivision of T. dimidiata, essential for designing effective control strategies.
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