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Bilheiro AB, Costa GDS, Araújo MS, Ribeiro WAR, Finamore-Araújo P, Moreira OC, Medeiros JF, Fontes G, Camargo LMA. Detection and Genotyping of Trypanosoma cruzi Samples in Species of Genus Rhodnius from Different Environments in the Brazilian Amazon. Vector Borne Zoonotic Dis 2024; 24:95-103. [PMID: 38165392 DOI: 10.1089/vbz.2023.0082] [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] [Indexed: 01/03/2024] Open
Abstract
Background: In the Amazon region, several species of triatomines occur in the natural environments. Among them, species of the genus Rhodnius are a risk to human populations due to their high rates of infection with Trypanosoma cruzi. The aim of this study was to identify the T. cruzi genotypes in Rhodnius specimens and their relationship with sylvatic hosts from different environments in the Brazilian Amazon. Methods: A total of 492 triatomines were collected from the municipalities of Monte Negro, Rondônia state, and Humaitá, Amazonas state, 382 of them being nymphs and 110 adults. Genotyping of T. cruzi in six discrete typing units (DTUs) was performed using conventional multilocus PCR. The triatomines that were positive for T. cruzi and engorged with blood were also targeted for amplification of the cytochrome B (cytB) gene to identify bloodmeal sources. Results: Of the 162 positive samples, the identified DTUs were TcI (87.65%) and TcIV (12.35%). It was observed that 102 specimens were engorged with a variety of bloodmeals. Triatomines infected with TcI were associated with DNA of all identified vertebrates, except Plecturocebus brunneus. TcIV was detected in triatomines that fed on Coendou prehensilis, Didelphis marsupialis, Mabuya nigropunctata, P. brunneus, Pithecia irrorata, Sapajus apella, and Tamandua tetradactyla. Conclusion: Results highlight the need to understand the patterns of T. cruzi genotypes in Rhodnius spp. and their association with sylvatic hosts to better elucidate their role in the transmission of Chagas disease in the Amazon region.
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Affiliation(s)
- Adriana Benatti Bilheiro
- Programa de Pós-Graduação em Ciências da Saúde, Universidade Federal de São João del Rei, Divinópolis, MG, Brazil
| | - Glaucilene da Silva Costa
- Laboratório de Saúde Pública-LACEN, Núcleo de Biologia Animal e Entomologia Médica, Porto Velho, RO, Brazil
| | - Maisa Silva Araújo
- Fundação Oswaldo Cruz/Fiocruz Rondônia, Porto Velho, RO, Brazil
- Centro de Pesquisa em Medicina Tropical de Rondônia (CEPEM)/Secretaria de Estado da Saúde de Rondônia, Porto Velho, RO, Brazil
| | | | - Paula Finamore-Araújo
- Laboratório de Virologia e Parasitologia Molecular, Instituto Oswaldo Cruz/IOC, Rio de Janeiro, RJ, Brazil
| | - Otacílio C Moreira
- Laboratório de Virologia e Parasitologia Molecular, Instituto Oswaldo Cruz/IOC, Rio de Janeiro, RJ, Brazil
| | - Jansen Fernandes Medeiros
- Fundação Oswaldo Cruz/Fiocruz Rondônia, Porto Velho, RO, Brazil
- Programa de Pós-Graduação em Biologia Experimental, Fundação Universidade Federal de Rondônia, Porto Velho, RO, Brazil
- Instituto Nacional de Epidemiologia da Amazônia Ocidental INCT-EPIAMO, Porto Velho, RO, Brazil
| | - Gilberto Fontes
- Programa de Pós-Graduação em Ciências da Saúde, Universidade Federal de São João del Rei, Divinópolis, MG, Brazil
- Instituto Nacional de Epidemiologia da Amazônia Ocidental INCT-EPIAMO, Porto Velho, RO, Brazil
| | - Luís Marcelo Aranha Camargo
- Programa de Pós-Graduação em Ciências da Saúde, Universidade Federal de São João del Rei, Divinópolis, MG, Brazil
- Centro de Pesquisa em Medicina Tropical de Rondônia (CEPEM)/Secretaria de Estado da Saúde de Rondônia, Porto Velho, RO, Brazil
- Instituto de Ciências Biomédicas 5, Universidade de São Paulo (ICB-5, USP), Monte Negro, RO, Brazil
- Instituto Nacional de Epidemiologia da Amazônia Ocidental INCT-EPIAMO, Porto Velho, RO, Brazil
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Barnabé C, Brenière SF, Santillán-Guayasamín S, Douzery EJP, Waleckx E. Revisiting gene typing and phylogeny of Trypanosoma cruzi reference strains: Comparison of the relevance of mitochondrial DNA, single-copy nuclear DNA, and the intergenic region of mini-exon gene. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2023; 115:105504. [PMID: 37739149 DOI: 10.1016/j.meegid.2023.105504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/12/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023]
Abstract
Chagas disease is a widespread neglected disease in Latin America. Trypanosoma cruzi, the causative agent of the disease, is currently subdivided into six DTUs (discrete typing units) named TcI-TcVI, and although no clear association has been found between parasite genetics and different clinical outcomes of the disease or different transmission cycles, genetic characterization of T. cruzi strains remains crucial for integrated epidemiological studies. Numerous markers have been used for this purpose, although without consensus. These include mitochondrial genes, single or multiple-copy nuclear genes, ribosomal RNA genes, and the intergenic region of the repeated mini-exon gene. To increase our knowledge of these gene sequences and their usefulness for strain typing, we sequenced fragments of three mitochondrial genes, nine single-copy nuclear genes, and the repeated intergenic part of the mini-exon gene by Next Generation Sequencing (NGS) on a sample constituted of 16 strains representative of T. cruzi genetic diversity, to which we added the corresponding genetic data of the 38 T. cruzi genomes fully sequenced until 2022. Our results show that single-copy nuclear genes remain the gold standard for characterizing T. cruzi strains; the phylogenetic tree from concatenated genes (3959 bp) confirms the six DTUs previously recognized and provides additional information about the alleles present in the hybrid strains. In the tree built from the three mitochondrial concatenated genes (1274 bp), three main clusters are identified, including one with TcIII, TcIV, TcV, and TcVI DTUs which are not separated. Nevertheless, mitochondrial markers remain necessary for detecting introgression and heteroplasmy. The phylogenetic tree built from the sequence alignment of the repeated mini-exon gene fragment (327 bp) displayed six clusters, but only TcI was associated with a single cluster. The sequences obtained from strains belonging to the other DTUs were scattered into different clusters. Therefore, while the mini-exon marker may bring, for some biological samples, some advantages in terms of sensibility due to its repeated nature, mini-exon sequences must be used with caution and, when possible, avoided for T. cruzi typing and phylogenetic studies.
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Affiliation(s)
- Christian Barnabé
- Institut de Recherche pour le Développement (IRD), UMR INTERTRYP IRD, CIRAD, University of Montpellier, Montpellier, France.
| | - Simone Frédérique Brenière
- Institut de Recherche pour le Développement (IRD), UMR INTERTRYP IRD, CIRAD, University of Montpellier, Montpellier, France
| | - Soledad Santillán-Guayasamín
- Institut de Recherche pour le Développement (IRD), UMR INTERTRYP IRD, CIRAD, University of Montpellier, Montpellier, France; Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland.
| | - Emmanuel J P Douzery
- Institut des Sciences de l'Évolution de Montpellier (ISEM), CNRS, IRD, EPHE, Université de Montpellier, Montpellier, France.
| | - Etienne Waleckx
- Institut de Recherche pour le Développement (IRD), UMR INTERTRYP IRD, CIRAD, University of Montpellier, Montpellier, France; Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Mexico; ACCyC, Asociación Chagas con Ciencia y Conocimiento, A. C, Orizaba, Mexico.
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Brandão EMV, Xavier SCC, Carvalhaes JG, D’Andrea PS, Lemos FG, Azevedo FC, Cássia-Pires R, Jansen AM, Roque ALR. Trypanosomatids in Small Mammals of an Agroecosystem in Central Brazil: Another Piece in the Puzzle of Parasite Transmission in an Anthropogenic Landscape. Pathogens 2019; 8:pathogens8040190. [PMID: 31615153 PMCID: PMC6963188 DOI: 10.3390/pathogens8040190] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/08/2019] [Accepted: 10/11/2019] [Indexed: 12/18/2022] Open
Abstract
We surveyed infection by Trypanosoma spp. and Leishmania spp. in small wild mammals from Cumari, Goiás State aiming to investigate the diversity of trypanosomatid in a modified landscape of the Brazilian Cerrado (and possible infection overlapping with canids from the same area). Blood, skin, spleen, and liver samples were collected for parasitological, serological, and molecular assays. Gracilinanus agilis was the most abundant species (N = 70; 48.6%) and it was the only one with patent parasitemia. Characterization by mini-exon and 18SrDNA targets were achieved in 7/10 hemocultures with positive fresh blood examination, which confirmed the T. cruzi infection by Discrete Typing Units (DTU) TcI in single (N = 2) and mixed infections with other DTUs (N = 5). T. rangeli and T. dionisii were detected in skin fragments from Didelphis albiventris and Oecomys cleberi, respectively. G. agilis were found to be infected by L. braziliensis and L. guyanensis, while Leishmania sp. DNA was detected in the liver of Oligoryzomys nigripes and Calomys expulsus. Subpatent infection by T. cruzi and Leishmania sp. was serologically detected in 15% and 9% of the small mammal fauna, respectively. Small mammals from Cumari are included in T. cruzi and Leshmania spp. transmission cycles, showing a higher diversity of trypanosomatid species and/or genotypes than that observed in canids of the same agroecosystem.
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Affiliation(s)
- Elida M. V. Brandão
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ 21040900, Brasil; (E.M.V.B.); (S.C.C.X.); (A.M.J.)
| | - Samanta C. C. Xavier
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ 21040900, Brasil; (E.M.V.B.); (S.C.C.X.); (A.M.J.)
| | - Jeiel G. Carvalhaes
- Laboratório de Biologia e Parasitologia de Mamíferos Silvestres Reservatórios, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ 21040900, Brasil; (J.G.C.); (P.S.D.)
| | - Paulo S. D’Andrea
- Laboratório de Biologia e Parasitologia de Mamíferos Silvestres Reservatórios, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ 21040900, Brasil; (J.G.C.); (P.S.D.)
| | - Frederico G. Lemos
- Programa de Conservação Mamíferos do Cerrado (PCMC)–Unidade Acadêmica Especial de Biotecnologia, Universidade Federal de Goiás/Regional Catalão, Catalão, GO 75704020, Brasil; (F.G.L.); (F.C.A.)
| | - Fernanda C. Azevedo
- Programa de Conservação Mamíferos do Cerrado (PCMC)–Unidade Acadêmica Especial de Biotecnologia, Universidade Federal de Goiás/Regional Catalão, Catalão, GO 75704020, Brasil; (F.G.L.); (F.C.A.)
| | - Renata Cássia-Pires
- Laboratório de Biologia de Parasitos, Centro de Ciências da Saúde, Departamento de Ciências Farmacêuticas, Universidade Federal do Rio Grande do Norte, Natal, RN 59012570, Brasil;
| | - Ana M. Jansen
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ 21040900, Brasil; (E.M.V.B.); (S.C.C.X.); (A.M.J.)
| | - André L. R. Roque
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ 21040900, Brasil; (E.M.V.B.); (S.C.C.X.); (A.M.J.)
- Correspondence: ; Tel.: +55-21-2562-1416; Fax: +55-21-2562-1609
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Infection by Trypanosoma cruzi in the central nervous system in non-human mammals: a systematic review. Parasitology 2019; 146:983-1005. [PMID: 30873928 DOI: 10.1017/s0031182019000210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Currently, the types and distribution of the lesions induced in the central nervous system (CNS) by Trypanosoma cruzi remain unclear as the available evidence is based on fragmented data. Therefore, we developed a systematic review to analyse the main characteristics of the CNS lesions in non-human hosts infected. From a structured search on the PubMed/Medline and Scopus platforms, 32 studies were retrieved, subjected to data extraction and methodological bias analysis. Our results show that the most frequent alterations in the CNS are the presence of different forms of T. cruzi and intense lymphocytes infiltrates. The encephalon is the main target of T. cruzi, and inflammatory changes in the CNS are more frequent and severe in the acute phase of infection. The parasite's genotype and phenotype are associated with the tropism and severity of the CNS lesions. The methodological limitations found in the studies were divergences in inoculation pathways, under-reporting of animal age and weight, sample calculation strategies and histopathological characterization. Since the changes were dependent on the pathogenicity and virulence of the T. cruzi strains, the genotype and phenotype characterization of the parasite are extremely relevant to predict changes in the CNS and the neurological manifestations associated with Chagas' disease.
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Jansen AM, Xavier SCDC, Roque ALR. Trypanosoma cruzi transmission in the wild and its most important reservoir hosts in Brazil. Parasit Vectors 2018; 11:502. [PMID: 30189896 PMCID: PMC6127949 DOI: 10.1186/s13071-018-3067-2] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 08/17/2018] [Indexed: 11/26/2022] Open
Abstract
Trypanosoma cruzi (Kinetoplastea: Trypanosomatidae) infects all tissues of its hosts, which along with humans, include hundreds of mammalian species in the Americas. The epidemiology of T. cruzi has been changing in that currently the majority of the cases and/or outbreaks of Chagas disease occur by the ingestion of comestibles contaminated by T. cruzi metacyclic forms. These cases/outbreaks occur in distinct regional scenarios, mainly in the Amazon biome and are related to the local interaction mode of humans with their surroundings, as well as with the overall local ecological peculiarities. As trypanosomiasis caused by T. cruzi is primarily a zoonosis, understanding the variables that influences its transmission in the wild as well as the role played by the extant fauna in the maintenance of the parasite, is critical in establishing control measures. Here, we present the results of our studies of T. cruzi infection of free ranging wild mammalian fauna in the five biomes of Brazil, a country of continental dimensions. From 1992 up to 2017, we examined a total of 6587 free-ranging non-volant wild mammal specimens. Our studies found that 17% of mammals were seropositive and 8% of all animals displayed positive hemocultures indicative of high parasitemia and, consequently, of infectivity potential. We observed that opossums, mainly Philander spp. and Didelphis spp., the coati Nasua nasua, the capuchin monkey Sapajus libidinosus and the golden lion tamarin Leontopithecus rosalia, were mammal taxa that demonstrated higher rates of positive hemocultures. Additionally, Didelphis spp. demonstrated to be a competent bioaccumulator of TcI diversity. Chiroptera were distinguished for hosting the greatest diversity of species and genotypes of Trypanosoma spp. Additionally the observation of the higher host range of some Trypanosoma spp., shows the need to reassess the ecology of representatives of the taxon. Altogether, our results showed that each locality, may display distinct enzootiological and epidemiological scenarios that must be taken into account when it comes to establishing control and/or clarification campaigns of the local population.
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Affiliation(s)
- Ana Maria Jansen
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz/FIOCRUZ, Av. Brasil 4365, Rio de Janeiro, RJ, CEP. 21040-360, Brazil.
| | - Samanta Cristina das Chagas Xavier
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz/FIOCRUZ, Av. Brasil 4365, Rio de Janeiro, RJ, CEP. 21040-360, Brazil
| | - André Luiz Rodrigues Roque
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz/FIOCRUZ, Av. Brasil 4365, Rio de Janeiro, RJ, CEP. 21040-360, Brazil
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Barros JHS, Xavier SCC, Bilac D, Lima VS, Dario MA, Jansen AM. Identification of novel mammalian hosts and Brazilian biome geographic distribution of Trypanosoma cruzi TcIII and TcIV. Acta Trop 2017; 172:173-179. [PMID: 28499908 DOI: 10.1016/j.actatropica.2017.05.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 04/24/2017] [Accepted: 05/02/2017] [Indexed: 12/21/2022]
Abstract
Trypanosoma cruzi is a parasitic protozoan responsible for Chagas disease. Seven different Discrete Typing Units (DTUs) of T. cruzi are currently identified in nature: TcI-TcVI, and TcBat whose distribution patterns in nature, hosts/reservoirs and eco-epidemiological importance are still little known. Here, we present novel data on the geographic distribution and diversity of mammalian hosts and vectors of T. cruzi DTUs TcIII and TcIV. In this study, we analyzed 61 T. cruzi isolates obtained from 18 species of mammals (five orders) and two Hemiptera genera. Samples were collected from five Brazilian biomes (Pantanal, Caatinga, Cerrado, Atlantic Rainforest, and Amazon) previously characterized as Z3 or mixed infection (TcI-Z3) by mini-exon gene PCR. To identify TcIII and TcIV genotypes, we applied restriction fragment length polymorphism analysis to the PCR-amplified histone 3 gene. DTUs TcIII and TcIV were identified in single and mixed infections from wide dispersion throughout five Brazilian biomes studied, with TcIV being the most common. Pantanal was the biome that displayed the largest number of samples characterized as TcIII and TcIV in single and mixed infections, followed by Atlantic Rainforest and Amazon. Species from the Didelphimorphia order displayed the highest frequency of infection and were found in all five biomes. We report, for the first time, the infection of a species of the Artiodactyla order by DTU TcIII. In addition, we describe new host species: five mammals (marsupials and rodents) and two genera of Hemiptera. Our data indicate that DTUs TcIII and TcIV are more widespread and infect a larger number of mammalian species than previously thought. In addition, they are transmitted in restricted foci and cycles, but in different microhabitats and areas with distinct ecological profiles. Finally, we show that DTUs TcIII and TcIV do not present any specific association with biomes or host species.
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ACOSTA NIDIA, LÓPEZ ELSA, LEWIS MICHAELD, LLEWELLYN MARTINS, GÓMEZ ANA, ROMÁN FABIOLA, MILES MICHAELA, YEO MATTHEW. Hosts and vectors of Trypanosoma cruzi discrete typing units in the Chagas disease endemic region of the Paraguayan Chaco. Parasitology 2017; 144:884-898. [PMID: 28179034 PMCID: PMC5471830 DOI: 10.1017/s0031182016002663] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 12/29/2022]
Abstract
Active Trypanosoma cruzi transmission persists in the Gran Chaco region, which is considered hyperendemic for Chagas disease. Understanding domestic and sylvatic transmission cycles and therefore the relationship between vectors and mammalian hosts is crucial to designing and implementing improved effective control strategies. Here we describe the species of triatomine vectors and the sylvatic mammal reservoirs of T. cruzi, in different localities of the Paraguayan and Bolivian Chaco. We identify the T. cruzi genotypes discrete typing units (DTUs) and provide a map of their geographical distribution. A total of 1044 triatomines and 138 sylvatic mammals were captured. Five per cent of the triatomines were microscopically positive for T. cruzi (55 Triatoma infestans from Paraguay and one sylvatic Triatoma guasayana from Bolivia) and 17 animals (12·3%) comprising eight of 28 (28·5%) Dasypus novemcinctus, four of 27 (14·8%) Euphractus sexcinctus, three of 64 (4·7%) Chaetophractus spp. and two of 14 (14·3%) Didelphis albiventris. The most common DTU infecting domestic triatomine bugs was TcV (64%), followed by TcVI (28%), TcII (6·5%) and TcIII (1·5%). TcIII was overwhelmingly associated with armadillo species. We confirm the primary role of T. infestans in domestic transmission, armadillo species as the principal sylvatic hosts of TcIII, and consider the potential risk of TcIII as an agent of Chagas disease in the Chaco.
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Affiliation(s)
- NIDIA ACOSTA
- Departamento de Medicina Tropical, Instituto de Investigaciones en Ciencias de la Salud, Universidad Nacional de Asunción – UNA, San Lorenzo CP 2160, Paraguay
| | - ELSA LÓPEZ
- Departamento de Medicina Tropical, Instituto de Investigaciones en Ciencias de la Salud, Universidad Nacional de Asunción – UNA, San Lorenzo CP 2160, Paraguay
| | - MICHAEL D. LEWIS
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - MARTIN S. LLEWELLYN
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - ANA GÓMEZ
- Centro para el Desarrollo de la Investigación Científica (CEDIC)/Díaz Gill Medicina Laboratorial/Fundación Moisés Bertoni, Asunción, Paraguay
| | - FABIOLA ROMÁN
- Centro para el Desarrollo de la Investigación Científica (CEDIC)/Díaz Gill Medicina Laboratorial/Fundación Moisés Bertoni, Asunción, Paraguay
| | - MICHAEL A. MILES
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - MATTHEW YEO
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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Dario MA, Rodrigues MS, Barros JHDS, Xavier SCDC, D’Andrea PS, Roque ALR, Jansen AM. Ecological scenario and Trypanosoma cruzi DTU characterization of a fatal acute Chagas disease case transmitted orally (Espírito Santo state, Brazil). Parasit Vectors 2016; 9:477. [PMID: 27580853 PMCID: PMC5006519 DOI: 10.1186/s13071-016-1754-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 08/12/2016] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Trypanosoma cruzi infection via oral route results in outbreaks or cases of acute Chagas disease (ACD) in different Brazilian regions and poses a novel epidemiological scenario. In the Espírito Santo state (southeastern Brazil), a fatal case of a patient with ACD led us to investigate the enzootic scenario to avoid the development of new cases. At the studied locality, Triatoma vitticeps exhibited high T. cruzi infection rates and frequently invaded residences. METHODS Sylvatic and domestic mammals in the Rio da Prata locality, where the ACD case occurred, and in four surrounding areas (Baia Nova, Buenos Aires, Santa Rita and Todos os Santos) were examined and underwent parasitological and serological tests. Triatomines were collected for a fecal material exam, culturing and mini-exon gene molecular characterization, followed by RFLP-PCR of H3/Alul. Paraffin-embedded cardiac tissue of a patient was washed with xylene to remove paraffin and DNA was extracted using the phenol-chloroform method. For genotype characterization, PCR was performed to amplify the 1f8, GPI and 18S rRNA genes. In the case of V7V8 SSU rRNA, the PCR products were molecularly cloned. PCR products were sequenced and compared to sequences in GenBank. Phylogenetic analysis using maximum likelihood method with 1000 bootstrap replicates was performed. RESULTS None of the animals showed positive hemocultures. Three rodents and two dogs showed signs of infection, as inferred from borderline serological titers. T. vitticeps was the only triatomine species identified and showed T. cruzi infection by DTUs TcI and TcIV. The analysis of cardiac tissue DNA showed mixed infection by T. cruzi (DTUs I, II, III and IV) and Trypanosoma dionisii. CONCLUSIONS Each case or outbreak of ACD should be analyzed as a particular epidemiological occurrence. The results indicated that mixed infections in humans may play a role in pathogenicity and may be more common than is currently recognized. Direct molecular characterization from biological samples is essential because this procedure avoids parasite selection. T. dionisii may under certain and unknown circumstances infect humans. The distribution of T. cruzi DTUS TcIII and TcIV in Brazilian biomes is broader than has been assumed to date.
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Affiliation(s)
- Maria Augusta Dario
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Rio de Janeiro Brazil
| | - Marina Silva Rodrigues
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Rio de Janeiro Brazil
| | | | | | - Paulo Sérgio D’Andrea
- Laboratory of Biology and Parasitology of Wild Reservoir Mammals, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Rio de Janeiro Brazil
| | - André Luiz Rodrigues Roque
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Rio de Janeiro Brazil
| | - Ana Maria Jansen
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Rio de Janeiro Brazil
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Brenière SF, Waleckx E, Barnabé C. Over Six Thousand Trypanosoma cruzi Strains Classified into Discrete Typing Units (DTUs): Attempt at an Inventory. PLoS Negl Trop Dis 2016; 10:e0004792. [PMID: 27571035 PMCID: PMC5003387 DOI: 10.1371/journal.pntd.0004792] [Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/31/2016] [Indexed: 01/06/2023] Open
Abstract
Trypanosoma cruzi, the causative agent of Chagas disease, presents wide genetic diversity. Currently, six discrete typing units (DTUs), named TcI to TcVI, and a seventh one called TcBat are used for strain typing. Beyond the debate concerning this classification, this systematic review has attempted to provide an inventory by compiling the results of 137 articles that have used it. A total of 6,343 DTU identifications were analyzed according to the geographical and host origins. Ninety-one percent of the data available is linked to South America. This sample, although not free of potential bias, nevertheless provides today's picture of T. cruzi genetic diversity that is closest to reality. DTUs were genotyped from 158 species, including 42 vector species. Remarkably, TcI predominated in the overall sample (around 60%), in both sylvatic and domestic cycles. This DTU known to present a high genetic diversity, is very widely distributed geographically, compatible with a long-term evolution. The marsupial is thought to be its most ancestral host and the Gran Chaco region the place of its putative origin. TcII was rarely sampled (9.6%), absent, or extremely rare in North and Central America, and more frequently identified in domestic cycles than in sylvatic cycles. It has a low genetic diversity and has probably found refuge in some mammal species. It is thought to originate in the south-Amazon area. TcIII and TcIV were also rarely sampled. They showed substantial genetic diversity and are thought to be composed of possible polyphyletic subgroups. Even if they are mostly associated with sylvatic transmission cycles, a total of 150 human infections with these DTUs have been reported. TcV and TcVI are clearly associated with domestic transmission cycles. Less than 10% of these DTUs were identified together in sylvatic hosts. They are thought to originate in the Gran Chaco region, where they are predominant and where putative parents exist (TcII and TcIII). Trends in host-DTU specificities exist, but generally it seems that the complexity of the cycles and the participation of numerous vectors and mammal hosts in a shared area, maintains DTU diversity.
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Affiliation(s)
- Simone Frédérique Brenière
- IRD-CIRAD, INTERTRYP (Interactions hôtes-vecteurs-parasites-environnement dans les maladies tropicales négligées dues aux Trypanosomatidés), IRD Center, Montpellier, France
- Pontificia Universidad Católica del Ecuador, Centro de Investigación para la Salud en América Latina (CISeAL), Quito, Ecuador
- * E-mail:
| | - Etienne Waleckx
- Centro de Investigaciones Regionales “Hideyo Noguchi”, Universidad Autónoma de Yucatán, Mérida, Yucatán, México
| | - Christian Barnabé
- IRD-CIRAD, INTERTRYP (Interactions hôtes-vecteurs-parasites-environnement dans les maladies tropicales négligées dues aux Trypanosomatidés), IRD Center, Montpellier, France
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Lisboa CV, Monteiro RV, Martins AF, Xavier SCDC, Lima VDS, Jansen AM. Infection with Trypanosoma cruzi TcII and TcI in free-ranging population of lion tamarins (Leontopithecus spp): an 11-year follow-up. Mem Inst Oswaldo Cruz 2015; 110:394-402. [PMID: 25946156 PMCID: PMC4489477 DOI: 10.1590/0074-02760140400] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 03/26/2015] [Indexed: 11/21/2022] Open
Abstract
Here, we present a review of the dataset resulting from the 11-years follow-up of
Trypanosoma cruzi infection in free-ranging populations of
Leontopithecus rosalia (golden lion tamarin) and
Leontopithecus chrysomelas (golden-headed lion tamarin) from
distinct forest fragments in Atlantic Coastal Rainforest. Additionally, we present
new data regarding T. cruzi infection of small mammals (rodents and
marsupials) that live in the same areas as golden lion tamarins and characterisation
at discrete typing unit (DTU) level of 77 of these isolates. DTU TcII was found to
exclusively infect primates, while TcI infected Didelphis aurita and
lion tamarins. The majority of T. cruzi isolates derived from
L. rosalia were shown to be TcII (33 out 42) Nine T.
cruzi isolates displayed a TcI profile. Golden-headed lion tamarins
demonstrated to be excellent reservoirs of TcII, as 24 of 26 T.
cruzi isolates exhibited the TcII profile. We concluded the following:
(i) the transmission cycle of T. cruzi in a same host species and
forest fragment is modified over time, (ii) the infectivity competence of the golden
lion tamarin population fluctuates in waves that peak every other year and (iii) both
golden and golden-headed lion tamarins are able to maintain long-lasting infections
by TcII and TcI.
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Affiliation(s)
- Cristiane Varella Lisboa
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil
| | - Rafael Veríssimo Monteiro
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil
| | - Andreia Fonseca Martins
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil
| | | | - Valdirene Dos Santos Lima
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil
| | - Ana Maria Jansen
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brasil
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Lima VDS, Xavier SCDC, Maldonado IFR, Roque ALR, Vicente ACP, Jansen AM. Expanding the knowledge of the geographic distribution of Trypanosoma cruzi TcII and TcV/TcVI genotypes in the Brazilian Amazon. PLoS One 2014; 9:e116137. [PMID: 25551227 PMCID: PMC4281250 DOI: 10.1371/journal.pone.0116137] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 12/04/2014] [Indexed: 11/19/2022] Open
Abstract
Trypanosoma cruzi infection is a complex sylvatic enzooty involving a wide range of animal species. Six discrete typing units (DTUs) of T. cruzi, named TcI to TcVI, are currently recognized. One unanswered question concerning the epidemiology of T. cruzi is the distribution pattern of TcII and hybrid DTUs in nature, including their virtual absence in the Brazilian Amazon, the current endemic area of Chagas disease in Brazil. Herein, we characterized biological samples that were collected in previous epizootiological studies carried out in the Amazon Basin in Brazil. We performed T. cruzi genotyping using four polymorphic genes to identify T. cruzi DTUs: mini-exon, 1f8, histone 3 and gp72. This analysis was conducted in the following biological samples: (i) two T. cruzi isolates obtained by culturing of stools from the triatomine species Rhodnius picttipes and (ii) five serum samples from dogs in which trypomastigotes were observed during fresh blood examination. We report for the first time the presence of TcII and hybrid DTUs (TcV/TcVI) in the Amazon region in mixed infections with TcI. Furthermore, sequencing of the constitutive gene, gp72, demonstrated diversity in TcII even within the same forest fragment. These data show that TcII is distributed in the five main Brazilian biomes and is likely more prevalent than currently described. It is very probable that there is no biological or ecological barrier to the transmission and establishment of any DTU in any biome in Brazil.
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Affiliation(s)
- Valdirene dos Santos Lima
- Laboratório de Biologia de Tripanosomatídeos, Fundação Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Irene Fabíola Roman Maldonado
- Laboratório de Biologia de Tripanosomatídeos, Fundação Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | - André Luiz Rodrigues Roque
- Laboratório de Biologia de Tripanosomatídeos, Fundação Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Carolina Paulo Vicente
- Laboratório de Genética Molecular de Microorganismos, Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Maria Jansen
- Laboratório de Biologia de Tripanosomatídeos, Fundação Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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Tenório M, Oliveira e Sousa L, Alves-Martin M, Paixão M, Rodrigues M, Starke-Buzetti W, Araújo Junior J, Lucheis S. Molecular identification of trypanosomatids in wild animals. Vet Parasitol 2014; 203:203-6. [DOI: 10.1016/j.vetpar.2014.02.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 02/07/2014] [Accepted: 02/10/2014] [Indexed: 11/26/2022]
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Rocha FL, Roque ALR, de Lima JS, Cheida CC, Lemos FG, de Azevedo FC, Arrais RC, Bilac D, Herrera HM, Mourão G, Jansen AM. Trypanosoma cruzi infection in neotropical wild carnivores (Mammalia: Carnivora): at the top of the T. cruzi transmission chain. PLoS One 2013; 8:e67463. [PMID: 23861767 PMCID: PMC3701642 DOI: 10.1371/journal.pone.0067463] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 05/18/2013] [Indexed: 01/22/2023] Open
Abstract
Little is known on the role played by Neotropical wild carnivores in the Trypanosoma cruzi transmission cycles. We investigated T. cruzi infection in wild carnivores from three sites in Brazil through parasitological and serological tests. The seven carnivore species examined were infected by T. cruzi, but high parasitemias detectable by hemoculture were found only in two Procyonidae species. Genotyping by Mini-exon gene, PCR-RFLP (1f8/Akw21I) and kDNA genomic targets revealed that the raccoon (Procyon cancrivorus) harbored TcI and the coatis (Nasua nasua) harbored TcI, TcII, TcIII-IV and Trypanosoma rangeli, in single and mixed infections, besides four T. cruzi isolates that displayed odd band patterns in the Mini-exon assay. These findings corroborate the coati can be a bioaccumulator of T. cruzi Discrete Typing Units (DTU) and may act as a transmission hub, a connection point joining sylvatic transmission cycles within terrestrial and arboreal mammals and vectors. Also, the odd band patterns observed in coatis' isolates reinforce that T. cruzi diversity might be much higher than currently acknowledged. Additionally, we assembled our data with T. cruzi infection on Neotropical carnivores' literature records to provide a comprehensive analysis of the infection patterns among distinct carnivore species, especially considering their ecological traits and phylogeny. Altogether, fifteen Neotropical carnivore species were found naturally infected by T. cruzi. Species diet was associated with T. cruzi infection rates, supporting the hypothesis that predator-prey links are important mechanisms for T. cruzi maintenance and dispersion in the wild. Distinct T. cruzi infection patterns across carnivore species and study sites were notable. Musteloidea species consistently exhibit high parasitemias in different studies which indicate their high infectivity potential. Mesocarnivores that feed on both invertebrates and mammals, including the coati, a host that can be bioaccumulator of T. cruzi DTU's, seem to take place at the top of the T. cruzi transmission chain.
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Affiliation(s)
- Fabiana Lopes Rocha
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
- Instituto Brasileiro para Medicina da Conservação, TRÍADE, Recife, Pernambuco, Brazil
- Programa de Conservação Mamíferos do Cerrado, PCMC, Araguari, Minas Gerais, Brazil
| | | | - Juliane Saab de Lima
- Programa de Pós-graduação em Ecologia e Conservação, Universidade Federal de Mato Grosso do Sul, UFMS, Campo Grande, Mato Grosso do Sul, Brazil
| | - Carolina Carvalho Cheida
- Programa de Pesquisa em Vida Selvagem/Projeto Carnívoros, Instituto de Pesquisas Cananéia (IPeC), Cananéia, São Paulo, Brazil
| | - Frederico Gemesio Lemos
- Programa de Conservação Mamíferos do Cerrado, PCMC, Araguari, Minas Gerais, Brazil
- Departamento de Ciências Biológicas, Universidade Federal de Goiás, UFG, Catalão, Goiás, Brazil
| | | | - Ricardo Corassa Arrais
- Programa de Conservação Mamíferos do Cerrado, PCMC, Araguari, Minas Gerais, Brazil
- Departamento de Medicina Preventiva e Saúde Animal, Universidade de São Paulo, USP, São Paulo, Brazil
| | - Daniele Bilac
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | | | - Guilherme Mourão
- Laboratório de Vida Selvagem, Empresa Brasileira de Pesquisa Agropecuária, Embrapa Pantanal, Corumbá, Mato Grosso do Sul, Brazil
| | - Ana Maria Jansen
- Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
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Herrera CP, Barnabé C, Brenière SF. Complex evolutionary pathways of the intergenic region of the mini-exon gene in Trypanosoma cruzi TcI: a possible ancient origin in the Gran Chaco and lack of strict genetic structuration. INFECTION GENETICS AND EVOLUTION 2013; 16:27-37. [PMID: 23380053 DOI: 10.1016/j.meegid.2012.12.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 12/21/2012] [Accepted: 12/24/2012] [Indexed: 10/27/2022]
Abstract
The TcI discrete typing unit (DTU) of Trypanosoma cruzi is the most abundant and widely spread in the Americas. It is found in a wide range of triatomine and mammal species, which are distributed throughout the Americas in sylvatic and domestic environments. Previous studies based on intergenic sequences of the mini-exon gene (SL-IR) have identified five genotype groups within TcI. Based in the large number of sequences available in GenBank, the present study conducted an exhaustive revision of the sequence variability of the SL-IR within TcI using 244 sequences from isolates, cellular or molecular clones, from 11 Latin American countries. First, the evolutionary branching between strains was examined by analyzing only the single nucleotide polymorphism (SNP) deleting the microsatellite region and the gaps from the total alignment. Then the variability of the microsatellite region was re-analyzed alone using principal component analysis (PCA). After haplotype reconstruction using the PHASE algorithm, because of the presence of several ambiguous nucleotides in the SNP region, a total of 131 different haplotypes were obtained. The topology reveals how difficult it is to identify an obvious structure in TcI for most of the parameters examined. Somewhat genetic and geographical structures exist, but no structure was depicted with cycle and host origins. Indeed, the long-lasting evolution with possible recombination events, the occurrence of several waves of geographical dispersions (old and recent), and the high flow of strains between sylvatic and domestic cycles partially hide the major evolutionary trends within TcI. Moreover, we identified several problems in previous analyses, and concluded that in absence of supplementary studies of TcI phylogeny with other genetic markers, it is hazardous to use only the mini-exon intergenic region as a relevant marker of the substructure within TcI.
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Affiliation(s)
- Claudia Patricia Herrera
- MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, Institut de Recherche pour le Développement (IRD), Representation in Bolivia, Av Hernando Siles 85290, CP 9214 La Paz, Bolivia.
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Teixeira ARL, Hecht MM, Guimaro MC, Sousa AO, Nitz N. Pathogenesis of chagas' disease: parasite persistence and autoimmunity. Clin Microbiol Rev 2011; 24:592-630. [PMID: 21734249 PMCID: PMC3131057 DOI: 10.1128/cmr.00063-10] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Acute Trypanosoma cruzi infections can be asymptomatic, but chronically infected individuals can die of Chagas' disease. The transfer of the parasite mitochondrial kinetoplast DNA (kDNA) minicircle to the genome of chagasic patients can explain the pathogenesis of the disease; in cases of Chagas' disease with evident cardiomyopathy, the kDNA minicircles integrate mainly into retrotransposons at several chromosomes, but the minicircles are also detected in coding regions of genes that regulate cell growth, differentiation, and immune responses. An accurate evaluation of the role played by the genotype alterations in the autoimmune rejection of self-tissues in Chagas' disease is achieved with the cross-kingdom chicken model system, which is refractory to T. cruzi infections. The inoculation of T. cruzi into embryonated eggs prior to incubation generates parasite-free chicks, which retain the kDNA minicircle sequence mainly in the macrochromosome coding genes. Crossbreeding transfers the kDNA mutations to the chicken progeny. The kDNA-mutated chickens develop severe cardiomyopathy in adult life and die of heart failure. The phenotyping of the lesions revealed that cytotoxic CD45, CD8(+) γδ, and CD8α(+) T lymphocytes carry out the rejection of the chicken heart. These results suggest that the inflammatory cardiomyopathy of Chagas' disease is a genetically driven autoimmune disease.
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Affiliation(s)
- Antonio R L Teixeira
- Chagas Disease Multidisciplinary Research Laboratory, University of Brasilia, Federal District, Brazil.
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Aliaga C, Brenière SF, Barnabé C. Further interest of miniexon multiplex PCR for a rapid typing of Trypanosoma cruzi DTU groups. INFECTION GENETICS AND EVOLUTION 2011; 11:1155-8. [DOI: 10.1016/j.meegid.2010.11.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 11/23/2010] [Accepted: 11/23/2010] [Indexed: 10/18/2022]
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Herrera HM, Rocha FL, Lisboa CV, Rademaker V, Mourão GM, Jansen AM. Food web connections and the transmission cycles of Trypanosoma cruzi and Trypanosoma evansi (Kinetoplastida, Trypanosomatidae) in the Pantanal Region, Brazil. Trans R Soc Trop Med Hyg 2011; 105:380-7. [PMID: 21600622 DOI: 10.1016/j.trstmh.2011.04.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 04/13/2011] [Accepted: 04/13/2011] [Indexed: 10/18/2022] Open
Abstract
We examined by parasitological tests (hemocultures and buffy coat) infection by Trypanosoma cruzi and T. evansi in blood samples from Leopardus pardalis, Cerdocyon thous and domestic dogs. Besides, 25 T. cruzi isolates previously derived from feral pigs and small wild mammals were here characterized by miniexon gene and demonstrated to be in the TcI genotype. Herein, we make an overall analysis of the transmission cycle of both trypanosome species in the light of the assemblage of data collected over the last seven years. The carnivore Nasua nasua was confirmed to play a major role in the transmission cycles of both T. cruzi and T. evansi since it was the species that had the higher prevalence and higher parasitemias by both flagellate species. In addition, our results show that both trypanosomatid species may be found throughout the Pantanal landscape, in all forest strata, as shown by the infection of carnivore, arboreal and terrestrial scansorial marsupial species in complex and seasonal transmission cycles. We propose that transmission of T. cruzi and T. evansi in the southern Pantanal region takes place via an intricate ecological trophic network involving generalist and specialist mammal species that are linked through a robust food-web connection.
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Affiliation(s)
- H M Herrera
- Laboratório de Biologia de Tripanosomatídeos, FIOCRUZ/RJ. Av. Brasil 4365, Rio de Janeiro, Brazil.
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