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Flores-López CA, Esquivias-Flores EA, Guevara-Carrizales A. Phylogenetic description of Trypanosoma cruzi isolates from Dipetalogaster maxima: Occurrence of TcI, TcIV, and TcIV-USA. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2023; 113:105465. [PMID: 37331498 DOI: 10.1016/j.meegid.2023.105465] [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: 04/21/2023] [Revised: 06/11/2023] [Accepted: 06/13/2023] [Indexed: 06/20/2023]
Abstract
Trypanosoma cruzi is the parasite responsible for Chagas disease. The parasite has been classified into six taxonomic assemblages: TcI-TcVI and TcBat (aka Discrete Typing Units or Near-Clades). No studies have focused on describing the genetic diversity of T. cruzi in the northwestern region of Mexico. Within the Baja California peninsula lives Dipetalogaster maxima, the largest vector species for CD. The study aimed to describe the genetic diversity of T. cruzi within D. maxima. A total of three Discrete Typing Units (DTUs) were found (TcI, TcIV, and TcIV-USA). TcI was the predominant DTU found (∼75% of samples), in concordance with studies from the southern USA, one sample was described as TcIV while the other ∼20% pertained to TcIV-USA, which has recently been proposed to have enough genetic divergence from TcIV, to merit its own DTU. Potential phenotype differences between TcIV and TcIV-USA should be assessed in future studies.
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Affiliation(s)
- Carlos A Flores-López
- Facultad de Ciencias, Universidad Autonoma de Baja California, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Colonia Playitas C.P. 22860, Ensenada, Baja California, Mexico.
| | - Esteban A Esquivias-Flores
- Facultad de Ciencias, Universidad Autonoma de Baja California, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Colonia Playitas C.P. 22860, Ensenada, Baja California, Mexico
| | - Aldo Guevara-Carrizales
- Facultad de Ciencias, Universidad Autonoma de Baja California, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Colonia Playitas C.P. 22860, Ensenada, Baja California, Mexico
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de Alba Alvarado MC, Torres Gutiérrez E, Cabrera Bravo M, Zenteno Galindo E, Villarreal Muñoz JA, Salazar Schettino PM, Bucio Torres MI. Main Cardiac Histopathologic Alterations in the Acute Phase of Trypanosoma cruzi Infection in a Murine Model. Pathogens 2023; 12:1084. [PMID: 37764892 PMCID: PMC10534729 DOI: 10.3390/pathogens12091084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 08/06/2023] [Accepted: 08/17/2023] [Indexed: 09/29/2023] Open
Abstract
Symptoms in the acute phase of Chagas disease are usually mild and nonspecific. However, after several years, severe complications like dilated heart failure and even death may arise in the chronic phase. Due to the lack of specific symptoms in the acute phase, the aim of this work was to describe and analyze the cardiac histopathology during this phase in a CD1 mouse model by assessing parasitism, fibrotic damage, and the presence and composition of a cellular infiltrate, to determine its involvement in the pathogenesis of lesions in the cardiac tissue. Our results indicate that the acute phase lasts about 62 days post-infection (dpi). A significant increase in parasitemia was observed since 15 dpi, reaching a maximum at 33 dpi (4.1 × 106). The presence of amastigote nests was observed at 15-62 dpi, with a maximum count of 27 nests at 35 dpi. An infiltrate consisting primarily of macrophages and neutrophils was found in the cardiac tissue within the first 30 days, but the abundance of lymphocytes showed an 8 ≥ fold increase at 40-62 dpi. Unifocal interstitial fibrosis was identified after 9 dpi, which subsequently showed a 16 ≥ fold increase at 40-60 dpi, along with a 50% mortality rate in the model under study. The increased area of fibrotic lesions revealed progression in the extent of fibrosis, mainly at 50-62 dpi. The presence of perivasculitis and thrombus circulation disorders was seen in the last days (62 dpi); finally, cases of myocytolysis were observed at 50 and 62 dpi. These histopathological alterations, combined with collagen deposition, seem to lead to the development of interstitial fibrosis and damage to the cardiac tissue during the acute phase of infection. This study provides a more complete understanding of the patterns of histopathological abnormalities involved in the acute phase, which could help the development of new therapies to aid the preclinical tests of drugs for their application in Chagas disease.
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Affiliation(s)
- Mariana C. de Alba Alvarado
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico; (M.C.d.A.A.); (E.T.G.); (M.C.B.)
| | - Elia Torres Gutiérrez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico; (M.C.d.A.A.); (E.T.G.); (M.C.B.)
| | - Margarita Cabrera Bravo
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico; (M.C.d.A.A.); (E.T.G.); (M.C.B.)
| | - Edgar Zenteno Galindo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico;
| | - José Antonio Villarreal Muñoz
- División de Investigación, Secretaria General, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico;
| | - Paz María Salazar Schettino
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico; (M.C.d.A.A.); (E.T.G.); (M.C.B.)
| | - Martha Irene Bucio Torres
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, Mexico City 04510, Mexico; (M.C.d.A.A.); (E.T.G.); (M.C.B.)
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Becker I, Miranda-Ortiz H, Fernández-Figueroa EA, Sánchez-Montes S, Colunga-Salas P, Grostieta E, Juárez-Gabriel J, Lozano-Sardaneta YN, Arce-Fonseca M, Rodríguez-Morales O, Meneses-Ruíz G, Pastén-Sánchez S, López Martínez I, González-Guzmán S, Paredes-Cervantes V, Moreira OC, Finamore-Araujo P, Canseco-Méndez JC, Coquis-Navarrete U, Rengifo-Correa L, González-Salazar C, Alfaro-Cortés MM, Falcón-Lezama JA, Tapia-Conyer R, Stephens CR. The Low Variability of Tc24 in Trypanosoma cruzi TcI as an Advantage for Chagas Disease Prophylaxis and Diagnosis in Mexico. Pathogens 2023; 12:pathogens12030368. [PMID: 36986290 PMCID: PMC10057631 DOI: 10.3390/pathogens12030368] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/28/2023] [Accepted: 02/03/2023] [Indexed: 02/25/2023] Open
Abstract
(1) Background: Chagas disease is the main neglected tropical disease in America. It is estimated that around 6 million people are currently infected with the parasite in Latin America, and 25 million live in endemic areas with active transmission. The disease causes an estimated economic loss of USD 24 billion dollars annually, with a loss of 75,200 working years per year of life; it is responsible for around ~12,000 deaths annually. Although Mexico is an endemic country that recorded 10,186 new cases of Chagas disease during the period of 1990–2017, few studies have evaluated the genetic diversity of genes that could be involved in the prophylaxis and/or diagnosis of the parasite. One of the possible candidates proposed as a vaccine target is the 24 kDa trypomastigote excretory–secretory protein, Tc24, whose protection is linked to the stimulation of T. cruzi-specific CD8+ immune responses. (2) Methods: The aim of the present study was to evaluate the fine-scale genetic diversity and structure of Tc24 in T. cruzi isolates from Mexico, and to compare them with other populations reported in the Americas with the aim to reconsider the potential role of Tc24 as a key candidate for the prophylaxis and improvement of the diagnosis of Chagas disease in Mexico. (3) Results: Of the 25 Mexican isolates analysed, 48% (12) were recovered from humans and 24% (6) recovered from Triatoma barberi and Triatoma dimidiata. Phylogenetic inferences revealed a polytomy in the T. cruzi clade with two defined subgroups, one formed by all sequences of the DTU I and the other formed by DTU II–VI; both subgroups had high branch support. Genetic population analysis detected a single (monomorphic) haplotype of TcI throughout the entire distribution across both Mexico and South America. This information was supported by Nei’s pairwise distances, where the sequences of TcI showed no genetic differences. (4) Conclusions: Given that both previous studies and the findings of the present work confirmed that TcI is the only genotype detected from human isolates obtained from various states of Mexico, and that there is no significant genetic variability in any of them, it is possible to propose the development of in silico strategies for the production of antigens that optimise the diagnosis of Chagas disease, such as quantitative ELISA methods that use this region of Tc24.
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Affiliation(s)
- Ingeborg Becker
- Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Correspondence: (I.B.); (C.R.S.)
| | - Haydee Miranda-Ortiz
- Unidad de Secuenciación, Instituto Nacional de Medicina Genómica, Mexico City 14610, Mexico
| | | | - Sokani Sánchez-Montes
- Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Laboratorio de Diagnóstico, Facultad de Ciencias Biológicas y Agropecuarias Región Poza Rica-Tuxpan, Universidad Veracruzana, Tuxpan de Rodríguez Cano 92870, Mexico
| | - Pablo Colunga-Salas
- Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Instituto de Biotecnología y Ecología Aplicada, Universidad Veracruzana, Xalapa de Enríquez 91090, Mexico
| | - Estefanía Grostieta
- Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Javier Juárez-Gabriel
- Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Laboratorio de Diagnóstico, Facultad de Ciencias Biológicas y Agropecuarias Región Poza Rica-Tuxpan, Universidad Veracruzana, Tuxpan de Rodríguez Cano 92870, Mexico
| | - Yokomi N. Lozano-Sardaneta
- Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Minerva Arce-Fonseca
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Mexico City 14080, Mexico
| | - Olivia Rodríguez-Morales
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Mexico City 14080, Mexico
| | - Gabriela Meneses-Ruíz
- Departamento de Parasitología, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City 01480, Mexico
| | - Sergio Pastén-Sánchez
- Departamento de Parasitología, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City 01480, Mexico
| | - Irma López Martínez
- Departamento de Parasitología, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City 01480, Mexico
| | - Saúl González-Guzmán
- Laboratorio del Banco Central de Sangre del Centro Médico Nacional “La Raza”, Instituto Mexicano del Seguro Social, Mexico City 02990, Mexico
- Departamento de Investigación, Hospital Regional de Alta Especialidad de Zumpango, Zumpango 55600, Mexico
| | - Vladimir Paredes-Cervantes
- Unidad de Investigación Médica en Inmunología e Infectología, Hospital de Infectología, Centro Médico Nacional “La Raza”, Instituto Mexicano del Seguro Social, Mexico City 02990, Mexico
| | - Otacilio C. Moreira
- Laboratorio de Biología Molecular e Doencas Endêmicas, Instituto Oswaldo Cruz, Fiocruz 21040900, RJ, Brazil
| | - Paula Finamore-Araujo
- Laboratorio de Biología Molecular e Doencas Endêmicas, Instituto Oswaldo Cruz, Fiocruz 21040900, RJ, Brazil
| | | | - Uriel Coquis-Navarrete
- Departamento de Genómica Poblacional, Instituto Nacional de Medicina Genómica, Mexico City 14610, Mexico
| | - Laura Rengifo-Correa
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | | | | | - Jorge A. Falcón-Lezama
- División Académica de Ciencias de la Salud, Universidad Juárez Autónoma de Tabasco, Villahermosa 86100, Mexico
| | - Roberto Tapia-Conyer
- Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Christopher R. Stephens
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Correspondence: (I.B.); (C.R.S.)
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Tibayrenc M, Ayala FJ. Microevolution and subspecific taxonomy of Trypanosoma cruzi. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2022; 103:105344. [PMID: 35926722 DOI: 10.1016/j.meegid.2022.105344] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
Trypanosoma cruzi, the agent of Chagas disease, is a highly polymorphic species, subdivided into 6 main evolutionary lineages or near-clades (formerly discrete typing units or DTUs). An additional near-clade (TC-bat) has recently been evidenced. This pattern is considered to be the result of predominant clonal evolution (PCE). PCE is compatible with occasional mating/hybridization, which do not break the prevalent pattern of clonal evolution, the main trait of it being the presence of Multigene Bifurcating Trees (MGBTs) at all evolutionary levels ("clonal frame"). The development of highly resolutive genetic (microsatellites*) and genomic (sequencing and multi-single nucleotide polymorphism {SNP}* typing) markers shows that PCE also operates at a microevolutionary* level within each of the near-clades ("Russian doll pattern"), in spite of occasional meiosis and hybridization events. Within each near-clade, one can evidence widespread clonal multilocus genotypes*, linkage disequilibrium*, Multigene Bifurcating Trees and lesser near-clades. The within near-clade population structure is like a miniature picture of that of the whole species, suggesting gradual rather than saltatory evolution. Additional data are required to evaluate the stability of these lesser near-clades in the long run and to evaluate the need for an adequate nomenclature for this microevolutionary level.
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Affiliation(s)
- Michel Tibayrenc
- Maladies Infectieuses et Vecteurs Ecologie, Génétique, Evolution et Contrôle, MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Institut de Recherche Pour le Développement, BP 6450134394 Montpellier Cedex 5, France.
| | - Francisco J Ayala
- Catedra Francisco Jose Ayala of Science, Technology, and Religion, University of Comillas, 28015 Madrid, Spain. 2 Locke Court, Irvine, CA 92617, USA
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Flores-López CA, Mitchell EA, Reisenman CE, Sarkar S, Williamson PC, Machado CA. Phylogenetic diversity of two common Trypanosoma cruzi lineages in the Southwestern United States. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2022; 99:105251. [PMID: 35183751 DOI: 10.1016/j.meegid.2022.105251] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
Trypanosoma cruzi is the causative agent of Chagas disease, a devastating parasitic disease endemic to Central and South America, Mexico, and the USA. We characterized the genetic diversity of Trypanosoma cruzi circulating in five triatomine species (Triatoma gerstaeckeri, T. lecticularia, T.indictiva, T. sanguisuga and T. recurva) collected in Texas and Southern Arizona using multilocus sequence typing (MLST) with four single-copy loci (cytochrome oxidase subunit II- NADH dehydrogensase subunit 1 region (COII-ND1), mismatch-repair class 2 (MSH2), dihydrofolate reductase-thymidylate synthase (DHFR-TS) and a nuclear gene with ID TcCLB.506529.310). All T. cruzi variants fall in two main genetic lineages: 75% of the samples corresponded to T. cruzi Discrete Typing Unit (DTU) I (TcI), and 25% to a North American specific lineage previously labelled TcIV-USA. Phylogenetic and sequence divergence analyses of our new data plus all previously published sequence data from those four loci collected in the USA, show that TcIV-USA is significantly different from any other previously defined T. cruzi DTUs. The significant level of genetic divergence between TcIV-USA and other T. cruzi DTUs should lead to an increased focus on understanding the epidemiological importance of this DTU, as well as its geographical range and pathogenicity in humans and domestic animals. Our findings further corroborate the fact that there is a high genetic diversity of the parasite in North America and emphasize the need for appropriate surveillance and vector control programs for Chagas disease in southern USA and Mexico.
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Affiliation(s)
- Carlos A Flores-López
- Department of Biology, University of Maryland, College Park, MD, USA; Facultad de Ciencias, Universidad Autónoma de Baja California, Ensenada, Baja California, Mexico
| | - Elizabeth A Mitchell
- Tick-Borne Disease Research Laboratory, Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, TX, USA; Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Carolina E Reisenman
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
| | - Sahotra Sarkar
- Department of Philosophy and Department of Integrative Biology, University of Texas, Austin, TX, USA
| | - Philip C Williamson
- Tick-Borne Disease Research Laboratory, Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, TX, USA; Creative Testing Solutions, Tempe, AZ, USA
| | - Carlos A Machado
- Department of Biology, University of Maryland, College Park, MD, USA.
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Hernandez-Castro LE, Villacís AG, Jacobs A, Cheaib B, Day CC, Ocaña-Mayorga S, Yumiseva CA, Bacigalupo A, Andersson B, Matthews L, Landguth EL, Costales JA, Llewellyn MS, Grijalva MJ. Population genomics and geographic dispersal in Chagas disease vectors: Landscape drivers and evidence of possible adaptation to the domestic setting. PLoS Genet 2022; 18:e1010019. [PMID: 35120121 PMCID: PMC8849464 DOI: 10.1371/journal.pgen.1010019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 02/16/2022] [Accepted: 01/06/2022] [Indexed: 12/19/2022] Open
Abstract
Accurate prediction of vectors dispersal, as well as identification of adaptations that allow blood-feeding vectors to thrive in built environments, are a basis for effective disease control. Here we adopted a landscape genomics approach to assay gene flow, possible local adaptation, and drivers of population structure in Rhodnius ecuadoriensis, an important vector of Chagas disease. We used a reduced-representation sequencing technique (2b-RADseq) to obtain 2,552 SNP markers across 272 R. ecuadoriensis samples from 25 collection sites in southern Ecuador. Evidence of high and directional gene flow between seven wild and domestic population pairs across our study site indicates insecticide-based control will be hindered by repeated re-infestation of houses from the forest. Preliminary genome scans across multiple population pairs revealed shared outlier loci potentially consistent with local adaptation to the domestic setting, which we mapped to genes involved with embryogenesis and saliva production. Landscape genomic models showed elevation is a key barrier to R. ecuadoriensis dispersal. Together our results shed early light on the genomic adaptation in triatomine vectors and facilitate vector control by predicting that spatially-targeted, proactive interventions would be more efficacious than current, reactive approaches. Re-infestation of recently insecticide-treated houses by wild/secondary triatomine, their potential adaptation to this new environment and capabilities to geographically disperse across multiple human communities jeopardise sustainable Chagas disease control. This is the first study in Chagas disease vectors that identifies genomic regions possibly linked to adaptations to the built environment and describes landscape drivers for accurate prediction of geographic dispersal. We sampled multiple domestic and wild Rhodnius ecuadoriensis population pairs across a mountainous terrain in southern Ecuador. We evidenced that triatomine movement from forest to built enviroments does occur at a high rate. In these highly connected population pairs we detected loci possibly linked to local adaptation among the genomic makers we evaluated and in doing so we pave the way for future triatomine genomic research. We highlighted that current haphazardous vector control in the zone will be hindered by reinfestation of triatomines from the forest. Instead, we recommend frequent and spatially-targeted vector control and provided a landacape genomic model that identifies highly connected and isolated triatomine populations to facilitate efficient vector control.
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Affiliation(s)
- Luis E. Hernandez-Castro
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- The Epidemiology, Economics and Risk Assessment Group, The Roslin Institute, Easter Bush Campus, The University of Edinburgh, Midlothian, United Kingdom
- * E-mail: (LEH-C); (MSL)
| | - Anita G. Villacís
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Arne Jacobs
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- Department of Natural Resources and the Environment, Cornell University, Ithaca, New York, United States of America
| | - Bachar Cheaib
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Casey C. Day
- Computational Ecology Lab, School of Public and Community Health Sciences, University of Montana, Missoula, Montana, United States of America
| | - Sofía Ocaña-Mayorga
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Cesar A. Yumiseva
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Antonella Bacigalupo
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Björn Andersson
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Louise Matthews
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Erin L. Landguth
- Computational Ecology Lab, School of Public and Community Health Sciences, University of Montana, Missoula, Montana, United States of America
- Center for Population Health Research, School of Public and Community Health Sciences, University of Montana, Missoula, Montana, United States of America
| | - Jaime A. Costales
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Martin S. Llewellyn
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- * E-mail: (LEH-C); (MSL)
| | - Mario J. Grijalva
- Centro de Investigación para la Salud en América Latina, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
- Infectious and Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
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Diversity and interactions among triatomine bugs, their blood feeding sources, gut microbiota and Trypanosoma cruzi in the Sierra Nevada de Santa Marta in Colombia. Sci Rep 2021; 11:12306. [PMID: 34112903 PMCID: PMC8192545 DOI: 10.1038/s41598-021-91783-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/25/2021] [Indexed: 12/14/2022] Open
Abstract
Chagas disease remains a major neglected disease in Colombia. We aimed to characterize Trypanosoma cruzi transmission networks in the Sierra Nevada de Santa Marta (SNSM) region, to shed light on disease ecology and help optimize control strategies. Triatomines were collected in rural communities and analyzed for blood feeding sources, parasite diversity and gut microbiota composition through a metagenomic and deep sequencing approach. Triatoma dimidiata predominated, followed by Rhodnius prolixus, Triatoma maculata, Rhodnius pallescens, Panstrongylus geniculatus and Eratyrus cuspidatus. Twenty-two species were identified as blood sources, resulting in an integrated transmission network with extensive connectivity among sylvatic and domestic host species. Only TcI parasites were detected, predominantly from TcIb but TcIa was also reported. The close relatedness of T. cruzi strains further supported the lack of separate transmission cycles according to habitats or triatomine species. Triatomine microbiota varied according to species, developmental stage and T. cruzi infection. Bacterial families correlated with the presence/absence of T. cruzi were identified. In conclusion, we identified a domestic transmission cycle encompassing multiple vector species and tightly connected with sylvatic hosts in the SNSM region, rather than an isolated domestic transmission cycle. Therefore, integrated interventions targeting all vector species and their contact with humans should be considered.
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Schwabl P, Maiguashca Sánchez J, Costales JA, Ocaña-Mayorga S, Segovia M, Carrasco HJ, Hernández C, Ramírez JD, Lewis MD, Grijalva MJ, Llewellyn MS. Culture-free genome-wide locus sequence typing (GLST) provides new perspectives on Trypanosoma cruzi dispersal and infection complexity. PLoS Genet 2020; 16:e1009170. [PMID: 33326438 PMCID: PMC7743988 DOI: 10.1371/journal.pgen.1009170] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 10/02/2020] [Indexed: 12/30/2022] Open
Abstract
Analysis of genetic polymorphism is a powerful tool for epidemiological surveillance and research. Powerful inference from pathogen genetic variation, however, is often restrained by limited access to representative target DNA, especially in the study of obligate parasitic species for which ex vivo culture is resource-intensive or bias-prone. Modern sequence capture methods enable pathogen genetic variation to be analyzed directly from host/vector material but are often too complex and expensive for resource-poor settings where infectious diseases prevail. This study proposes a simple, cost-effective 'genome-wide locus sequence typing' (GLST) tool based on massive parallel amplification of information hotspots throughout the target pathogen genome. The multiplexed polymerase chain reaction amplifies hundreds of different, user-defined genetic targets in a single reaction tube, and subsequent agarose gel-based clean-up and barcoding completes library preparation at under 4 USD per sample. Our study generates a flexible GLST primer panel design workflow for Trypanosoma cruzi, the parasitic agent of Chagas disease. We successfully apply our 203-target GLST panel to direct, culture-free metagenomic extracts from triatomine vectors containing a minimum of 3.69 pg/μl T. cruzi DNA and further elaborate on method performance by sequencing GLST libraries from T. cruzi reference clones representing discrete typing units (DTUs) TcI, TcIII, TcIV, TcV and TcVI. The 780 SNP sites we identify in the sample set repeatably distinguish parasites infecting sympatric vectors and detect correlations between genetic and geographic distances at regional (< 150 km) as well as continental scales. The markers also clearly separate TcI, TcIII, TcIV and TcV + TcVI and appear to distinguish multiclonal infections within TcI. We discuss the advantages, limitations and prospects of our method across a spectrum of epidemiological research.
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Affiliation(s)
- Philipp Schwabl
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Jalil Maiguashca Sánchez
- Centro de Investigación para la Salud en América Latina, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Jaime A. Costales
- Centro de Investigación para la Salud en América Latina, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Sofía Ocaña-Mayorga
- Centro de Investigación para la Salud en América Latina, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Maikell Segovia
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Universidad Central de Venezuela, Caracas, Venezuela
| | - Hernán J. Carrasco
- Laboratorio de Biología Molecular de Protozoarios, Instituto de Medicina Tropical, Universidad Central de Venezuela, Caracas, Venezuela
| | - Carolina Hernández
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Michael D. Lewis
- London School of Hygiene & Tropical Medicine, Keppel Street, London, United Kingdom
| | - Mario J. Grijalva
- Centro de Investigación para la Salud en América Latina, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
- Infectious and Tropical Disease Institute, Biomedical Sciences Department, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, United States of America
| | - Martin S. Llewellyn
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
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Bern C, Messenger LA, Whitman JD, Maguire JH. Chagas Disease in the United States: a Public Health Approach. Clin Microbiol Rev 2019; 33:e00023-19. [PMID: 31776135 PMCID: PMC6927308 DOI: 10.1128/cmr.00023-19] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Trypanosoma cruzi is the etiological agent of Chagas disease, usually transmitted by triatomine vectors. An estimated 20 to 30% of infected individuals develop potentially lethal cardiac or gastrointestinal disease. Sylvatic transmission cycles exist in the southern United States, involving 11 triatomine vector species and infected mammals such as rodents, opossums, and dogs. Nevertheless, imported chronic T. cruzi infections in migrants from Latin America vastly outnumber locally acquired human cases. Benznidazole is now FDA approved, and clinical and public health efforts are under way by researchers and health departments in a number of states. Making progress will require efforts to improve awareness among providers and patients, data on diagnostic test performance and expanded availability of confirmatory testing, and evidence-based strategies to improve access to appropriate management of Chagas disease in the United States.
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Affiliation(s)
- Caryn Bern
- University of California San Francisco School of Medicine, San Francisco, California, USA
| | | | - Jeffrey D Whitman
- University of California San Francisco School of Medicine, San Francisco, California, USA
| | - James H Maguire
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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10
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Detection of Trypanosoma cruzi strains circulating in Córdoba department (Colombia) isolated from triatomines (Hemiptera: Reduviidae) collected by the community. ACTA ACUST UNITED AC 2019; 39:265-277. [PMID: 31529814 DOI: 10.7705/biomedica.v39i2.3973] [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] [Received: 07/10/2017] [Indexed: 11/21/2022]
Abstract
INTRODUCTION From 2011 to 2016, 24 cases of Chagas disease were reported in Córdoba according to the national public health surveillance system (Sistema Nacional de Vigilancia en Salud Pública, Sivigila), but the information regarding Trypanosoma cruzi circulating strains and infection rates are unknown. OBJECTIVES To establish the triatomine species with which people come in contact and recognize as Chagas disease vectors, as well as to assess the infection with trypanosomes and make an exploratory approach to host feeding preferences with the participation of the local community. MATERIALS AND METHODS Triatomines sampling was conducted in 12 municipalities between 2011 and 2016; T. cruzi infection was established by k-PCR, SAT-PCR, while strain genotyping was done by mini-exon and SL-IR (spliced-leader intergenic region) sequence characterization. We also screened for blood sources. RESULTS Local community members collected the majority of triatomines and we identified three species: Rhodnius pallescens, Panstrongylus geniculatus, and Eratyrus cuspidatus. The overall T. cruzi infection rate in collected triatomines was 66.6% and we detected the TcIDOM and TcI sylvatic strains. Community-based insect collection allowed reporting the presence of P. geniculatus in two new disperse rural settlements, T. cruzi infection of P. geniculatus in Córdoba, and the first report of triatomines infected with T. cruzi in Montería municipality. CONCLUSIONS These results revealed the presence of triatomines infected with T. cruzi inside dwellings in five municipalities of Córdoba. The dominant circulating T. cruzi strain was TcIDOM, a genotype associated with human Chagas disease and cardiomyopathies in Colombia. Our results highlight the importance of local community participation in entomological surveillance tasks.
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11
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Evaluation of the multispecies coalescent method to explore intra-Trypanosoma cruzi I relationships and genetic diversity. Parasitology 2019; 146:1063-1074. [PMID: 31046857 DOI: 10.1017/s0031182019000428] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Chagas Disease is a zoonosis caused by the parasite Trypanosoma cruzi. Several high-resolution markers have subdivided T. cruzi taxon into at least seven lineages or Discrete Typing Units (DTUs) (TcI-TcVI and TcBat). Trypanosoma cruzi I is the most diverse and geographically widespread DTU. Recently a TcI genotype related to domestic cycles was proposed and named as TcIDOM. Herein, we combined traditional markers and housekeeping genes and applied a Multispecies Coalescent method to explore intra-TcI relationships, lineage boundaries and genetic diversity in a random set of isolates and DNA sequences retrieved from Genbank from different countries in the Americas. We found further evidence supporting TcIDOM as an independent and emerging genotype of TcI at least in Colombia and Venezuela. We also found evidence of high phylogenetic incongruence between parasite's gene trees (including introgression) and embedded species trees, and a lack of genetic structure among geography and hosts, illustrating the complex dynamics and epidemiology of TcI across the Americas. These findings provide novel insights into T. cruzi systematics and epidemiology and support the need to assess parasite diversity and lineage boundaries through hypothesis testing using different approaches to those traditionally employed, including the Bayesian Multispecies coalescent method.
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12
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A systematic review of the Trypanosoma cruzi genetic heterogeneity, host immune response and genetic factors as plausible drivers of chronic chagasic cardiomyopathy. Parasitology 2018; 146:269-283. [PMID: 30210012 DOI: 10.1017/s0031182018001506] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Chagas disease is a complex tropical pathology caused by the kinetoplastid Trypanosoma cruzi. This parasite displays massive genetic diversity and has been classified by international consensus in at least six Discrete Typing Units (DTUs) that are broadly distributed in the American continent. The main clinical manifestation of the disease is the chronic chagasic cardiomyopathy (CCC) that is lethal in the infected individuals. However, one intriguing feature is that only 30-40% of the infected individuals will develop CCC. Some authors have suggested that the immune response, host genetic factors, virulence factors and even the massive genetic heterogeneity of T. cruzi are responsible of this clinical pattern. To date, no conclusive data support the reason why a few percentages of the infected individuals will develop CCC. Therefore, we decided to conduct a systematic review analysing the host genetic factors, immune response, cytokine production, virulence factors and the plausible association of the parasite DTUs and CCC. The epidemiological and clinical implications are herein discussed.
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13
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Ramírez JD, Hernández C. Trypanosoma cruzi I: Towards the need of genetic subdivision?, Part II. Acta Trop 2018; 184:53-58. [PMID: 28495405 DOI: 10.1016/j.actatropica.2017.05.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 05/02/2017] [Accepted: 05/05/2017] [Indexed: 12/13/2022]
Abstract
Chagas disease is a complex zoonosis caused by the kinetoplastid parasite Trypanosoma cruzi. This protozoan exhibits remarkable genetic diversity evinced in at least six Discrete Typing Units (DTUs) with the foreseen emergence of a genotype associated to bats (TcBat). T. cruzi I is the DTU with the broadest geographical distribution and associated to severe cardiomyopathies. In 2011, we published a review questioning the need for genetic subdivision within TcI. However, after six years of intensive research. Herein, we attempted to determine if TcI should be subdivided or not in the light of the current genetic, biological, clinical and ecological data. The future perspectives are discussed.
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Zingales B. Trypanosoma cruzi genetic diversity: Something new for something known about Chagas disease manifestations, serodiagnosis and drug sensitivity. Acta Trop 2018; 184:38-52. [PMID: 28941731 DOI: 10.1016/j.actatropica.2017.09.017] [Citation(s) in RCA: 245] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 08/18/2017] [Accepted: 09/18/2017] [Indexed: 11/27/2022]
Abstract
The genetic diversity of Trypanosoma cruzi, the protozoan agent of Chagas disease, is widely recognized. At present, T. cruzi is partitioned into seven discrete typing units (DTUs), TcI-TcVI and Tcbat. This article reviews the present knowledge on the parasite population structure, the evolutionary relationships among DTUs and their distinct, but not exclusive ecological and epidemiological associations. Different models for the origin of hybrid DTUs are examined, which agree that genetic exchange among T. cruzi populations is frequent and has contributed to the present parasite population structure. The geographic distribution of the prevalent DTUs in humans from the southern United States to Argentina is here presented and the circumstantial evidence of a possible association between T. cruzi genotype and Chagas disease manifestations is discussed. The available information suggests that parasite strains detected in patients, regardless of the clinical presentation, reflect the principal DTU circulating in the domestic transmission cycles of a particular region. In contrast, in several orally transmitted outbreaks, sylvatic strains are implicated. As a consequence of the genotypic and phenotypic differences of T. cruzi strains and the differential geographic distribution of DTUs in humans, regional variations in the sensitivity of the serological tests are verified. The natural resistance to benznidazole and nifurtimox, verified in vivo and in vitro for some parasite stocks, is not associated with any particular DTU, and does not explain the marked difference in the anti-parasitic efficacy of both drugs in the acute and chronic phases of Chagas disease. Throughout this review, it is emphasized that the interplay between parasite and host genetics should have an important role in the definition of Chagas disease pathogenesis, anti-T. cruzi immune response and chemotherapy outcome and should be considered in future investigations.
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Affiliation(s)
- Bianca Zingales
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Avenida Professor Lineu Prestes 748, 05508-000 São Paulo, SP, Brazil.
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15
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Ribeiro AR, Lima L, de Almeida LA, Monteiro J, Moreno CJG, Nascimento JD, de Araújo RF, Mello F, Martins LPA, Graminha MAS, Teixeira MMG, Silva MS, Steindel M, da Rosa JA. Biological and Molecular Characterization of Trypanosoma cruzi Strains from Four States of Brazil. Am J Trop Med Hyg 2018; 98:453-463. [PMID: 29313485 PMCID: PMC5929169 DOI: 10.4269/ajtmh.16-0200] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 01/29/2017] [Indexed: 11/07/2022] Open
Abstract
Chagas disease affects between six and seven million people. Its etiological agent, Trypanosoma cruzi, is classified into six discrete typing units (DTUs). The biological study of 11 T. cruzi strains presented here included four parameters: growth kinetics, parasitemia curves, rate of macrophage infection, and serology to evaluate IgM, total IgG, IgG1, IgG2a, and IgG3. Sequencing of small subunit of ribosomal RNA (SSU rRNA)was performed and the T. cruzi strains were classified into three DTUs. When their growth in liver infusion tryptose medium was represented in curves, differences among the strains could be noted. The parasitemia profile varied among the strains from the TcI, TcII, and TcIII groups, and the 11 T. cruzi strains produced distinct parasitemia levels in infected BALB/c. The TcI group presented the highest rate of macrophage infection by amastigotes, followed by TcII and TcIII. Reactivity to immunoglobulins was observed in the TcI, TcII, and TcIII; all the animals infected with the different strains of T. cruzi showed anti-T. cruzi antibodies. The molecular study presented here resulted in the classification of the T. cruzi strains into the TcI (Bolivia, T lenti, Tm, SC90); TcII (Famema, SC96, SI8, Y); and TcIII (QMM3, QMM5, SI5) groups. These biological and molecular results from 11 T. cruzi strains clarified the factors involved in the biology of the parasite and its hosts. The collection of triatomine (vector) species, and the study of geographic distribution, as well as biological and molecular characterization of the parasite, will contribute to the reporting and surveillance measures in Brazilian states.
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Affiliation(s)
| | - Luciana Lima
- Department of Parasitology, Universidade de São Paulo, São Paulo, Brazil
| | - Larissa Aguiar de Almeida
- Department of Biological Sciences, Faculdade de Ciências Farmacêuticas da Universidade Estadual Paulista Júlio de Mesquita Filho, Araraquara, Brazil
| | - Joana Monteiro
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Cláudia Jassica Gonçalves Moreno
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Centro de Biociência, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | | | | | - Fernanda Mello
- Rio Grande do Sul State Health Secretariat, Porto Alegre, Brazil
| | | | - Márcia Aparecida Silva Graminha
- Department of Biological Sciences, Faculdade de Ciências Farmacêuticas da Universidade Estadual Paulista Júlio de Mesquita Filho, Araraquara, Brazil
| | | | - Marcelo Sousa Silva
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal
- Programa de Pós-graduação em Bioquímica, Departamento de Bioquímica, Centro de Biociência, Universidade Federal do Rio Grande do Norte, Natal, Brazil
- Departamento de Análises Clínicas e Toxicológicas, Centro de Ciências da Saúde, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | - Mário Steindel
- Department of Microbiology, Immunology, and Parasitology, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - João Aristeu da Rosa
- Department of Biological Sciences, Faculdade de Ciências Farmacêuticas da Universidade Estadual Paulista Júlio de Mesquita Filho, Araraquara, Brazil
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Curtis-Robles R, Auckland LD, Snowden KF, Hamer GL, Hamer SA. Analysis of over 1500 triatomine vectors from across the US, predominantly Texas, for Trypanosoma cruzi infection and discrete typing units. INFECTION GENETICS AND EVOLUTION 2017; 58:171-180. [PMID: 29269323 DOI: 10.1016/j.meegid.2017.12.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 12/04/2017] [Accepted: 12/15/2017] [Indexed: 01/01/2023]
Abstract
Across the Americas, triatomine insects harbor diverse strains of Trypanosoma cruzi (T. cruzi), agent of Chagas disease. Geographic patterns of vector infection and parasite strain associations, especially in vectors encountered by the public, may be useful in assessing entomological risk, but are largely unknown across the US. We collected Triatoma spp. from across the US (mainly Texas), in part using a citizen science initiative, and amplified T. cruzi DNA to determine infection prevalence and parasite discrete typing units (DTUs). We found 54.4% infection prevalence in 1510 triatomines of 6 species; prevalence in adult T. gerstaeckeri (63.3%; n=897) and T. lecticularia (66.7%; n=66) was greater than in T. sanguisuga (47.6%; n=315), T. indictiva (47.8% n=67), T. rubida (14.1%; n=64), and T. protracta (10.5%; n=19). The odds of infection in adults were 9.73 times higher than in nymphs (95% CI 4.46-25.83). PCR of the spliced leader intergenic region (SL-IR) and/or the putative lathosterol/episterol oxidase TcSC5D gene revealed exclusively T. cruzi DTUs TcI and TcIV; 5.5% of T. cruzi-positive samples were not successfully typed. T. gerstaeckeri (n=548) were more frequently infected with TcI (53.9%) than TcIV (34.4%), and 11.9% showed mixed TcI/TcIV infections. In contrast, T. sanguisuga (n=135) were more frequently infected with TcIV (79.3%) than TcI (15.6%), and 5.2% showed mixed infections. Relative abundance of parasite DTUs varied spatially, with both TcI and TcIV co-circulating in vectors in central Texas, while TcIV predominated in northern Texas. Given prior findings implicating TcI in human disease and TcI and TcIV in animal disease in the US, knowledge of spatial distribution of T. cruzi infection and DTUs in vectors is important to understanding public and veterinary health risk of T. cruzi infection.
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Affiliation(s)
- Rachel Curtis-Robles
- Department of Veterinary Integrative Biosciences, 4458 TAMU, Texas A&M University, College Station, TX 77843, USA.
| | - Lisa D Auckland
- Department of Veterinary Integrative Biosciences, 4458 TAMU, Texas A&M University, College Station, TX 77843, USA.
| | - Karen F Snowden
- Department of Veterinary Pathobiology, 4467 TAMU, Texas A&M University, College Station, TX 77843, USA.
| | - Gabriel L Hamer
- Department of Entomology, 2475 TAMU, Texas A&M University, College Station, TX 77843, USA.
| | - Sarah A Hamer
- Department of Veterinary Integrative Biosciences, 4458 TAMU, Texas A&M University, College Station, TX 77843, USA.
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17
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Reinhard K. Reestablishing rigor in archaeological parasitology. INTERNATIONAL JOURNAL OF PALEOPATHOLOGY 2017; 19:124-134. [PMID: 29198394 DOI: 10.1016/j.ijpp.2017.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 06/24/2017] [Indexed: 06/07/2023]
Abstract
Archaeological parasitology originated in the mid-twentieth century with interdisciplinary teams of specialists directed by archaeologists. The goals of such studies were detailed analyses of dietary, medicinal, and environmental factors that shaped the patterns of infection. By the 1970s, a cadre of unique coprolite analysts was trained to analyze macroscopic and microscopic remains for integrated reconstructions of the cultural determinants of parasitism. During these first phases of research, diagnostic rigor was maintained by direct training of specialists in parasitology and archaeology sub-disciplines including archaeobotany and archaeopalynology. Near the end of the twentieth century, however, "paleoparasitology" was defined as a separate field focusing on defining parasite distribution through time and space. Ironically, this focus resulted in an increase in misdiagnosis, especially prominent after 2000. Paleoparasitology does not explicitly include other specialized studies in it research design. Thus, dietary, environmental and medicinal inferences have been neglected or lost as samples were destroyed solely for the purpose of parasitological analysis. Without ancillary archaeological studies, paleoparasitology runs the risk of separation from archaeological context, thereby reducing its value to the archaeologists who recover samples for analysis.
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Affiliation(s)
- Karl Reinhard
- School of Natural Resources, Hardin Hall 719, University of Nebraska, Lincoln, Lincoln, NE 68583-0987, United States.
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18
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Rodrigues MS, Morelli KA, Jansen AM. Cytochrome c oxidase subunit 1 gene as a DNA barcode for discriminating Trypanosoma cruzi DTUs and closely related species. Parasit Vectors 2017; 10:488. [PMID: 29037251 PMCID: PMC5644147 DOI: 10.1186/s13071-017-2457-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 10/05/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The DNA barcoding system using the cytochrome c oxidase subunit 1 mitochondrial gene (cox1 or COI) is highly efficient for discriminating vertebrate and invertebrate species. In the present study, we examined the suitability of cox1 as a marker for Trypanosoma cruzi identification from other closely related species. Additionally, we combined the sequences of cox1 and the nuclear gene glucose-6-phosphate isomerase (GPI) to evaluate the occurrence of mitochondrial introgression and the presence of hybrid genotypes. METHODS Sixty-two isolates of Trypanosoma spp. obtained from five of the six Brazilian biomes (Amazon Forest, Atlantic Forest, Caatinga, Cerrado and Pantanal) were sequenced for cox1 and GPI gene fragments. Phylogenetic trees were reconstructed using neighbor-joining, maximum likelihood, parsimony and Bayesian inference methods. Molecular species delimitation was evaluated through pairwise intraspecific and interspecific distances, Automatic Barcode Gap Discovery, single-rate Poisson Tree Processes and multi-rate Poisson Tree Processes. RESULTS Both cox1 and GPI genes recognized and differentiated T. cruzi, Trypanosoma cruzi marinkellei, Trypanosoma dionisii and Trypanosoma rangeli. Cox1 discriminated Tcbat, TcI, TcII, TcIII and TcIV. Additionally, TcV and TcVI were identified as a single group. Cox1 also demonstrated diversity in the discrete typing units (DTUs) TcI, TcII and TcIII and in T. c. marinkellei and T. rangeli. Cox1 and GPI demonstrated TcI and TcII as the most genetically distant branches, and the position of the other T. cruzi DTUs differed according to the molecular marker. The tree reconstructed with concatenated cox1 and GPI sequences confirmed the separation of the subgenus Trypanosoma (Schizotrypanum) sp. and the T. cruzi DTUs TcI, TcII, TcIII and TcIV. The evaluation of single nucleotide polymorphisms (SNPs) was informative for DTU differentiation using both genes. In the cox1 analysis, one SNP differentiated heterozygous hybrids from TcIV sequences. In the GPI analysis one SNP discriminated Tcbat from TcI, while another SNP distinguished TcI from TcIII. CONCLUSIONS DNA barcoding using the cox1 gene is a reliable tool to distinguish T. cruzi from T. c. marinkellei, T. dionisii and T. rangeli and identify the main T. cruzi genotypes.
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Affiliation(s)
- Marina Silva Rodrigues
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Karina Alessandra Morelli
- Department of Ecology, Institute of Biology Roberto Alcantara Gomes, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Maria Jansen
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
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Dorn PL, McClure AG, Gallaspy MD, Waleckx E, Woods AS, Monroy MC, Stevens L. The diversity of the Chagas parasite, Trypanosoma cruzi, infecting the main Central American vector, Triatoma dimidiata, from Mexico to Colombia. PLoS Negl Trop Dis 2017; 11:e0005878. [PMID: 28957315 PMCID: PMC5619707 DOI: 10.1371/journal.pntd.0005878] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 08/17/2017] [Indexed: 01/02/2023] Open
Abstract
Little is known about the strains of Trypanosoma cruzi circulating in Central America and specifically in the most important vector in this region, Triatoma dimidiata. Approximately six million people are infected with T. cruzi, the causative agent of Chagas disease, which has the greatest negative economic impact and is responsible for ~12,000 deaths annually in Latin America. By international consensus, strains of T. cruzi are divided into six monophyletic clades called discrete typing units (DTUs TcI-VI) and a seventh DTU first identified in bats called TcBat. TcI shows the greatest geographic range and diversity. Identifying strains present and diversity within these strains is important as different strains and their genotypes may cause different pathologies and may circulate in different localities and transmission cycles, thus impacting control efforts, treatment and vaccine development. To determine parasite strains present in T. dimidiata across its geographic range from Mexico to Colombia, we isolated abdominal DNA from T. dimidiata and determined which specimens were infected with T. cruzi by PCR. Strains from infected insects were determined by comparing the sequence of the 18S rDNA and the spliced-leader intergenic region to typed strains in GenBank. Two DTUs were found: 94% of infected T. dimidiata contained TcI and 6% contained TcIV. TcI exhibited high genetic diversity. Geographic structure of TcI haplotypes was evident by Principal Component and Median-Joining Network analyses as well as a significant result in the Mantel test, indicating isolation by distance. There was little evidence of association with TcI haplotypes and host/vector or ecotope. This study provides new information about the strains circulating in the most important Chagas vector in Central America and reveals considerable variability within TcI as well as geographic structuring at this large geographic scale. The lack of association with particular vectors/hosts or ecotopes suggests the parasites are moving among vectors/hosts and ecotopes therefore a comprehensive approach, such as the Ecohealth approach that makes houses refractory to the vectors will be needed to successfully halt transmission of Chagas disease.
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Affiliation(s)
- Patricia L. Dorn
- Loyola University New Orleans, New Orleans, Louisiana, United States of America
| | - Annie G. McClure
- Loyola University New Orleans, New Orleans, Louisiana, United States of America
| | - Meghan D. Gallaspy
- Loyola University New Orleans, New Orleans, Louisiana, United States of America
| | | | - Adrienne S. Woods
- Loyola University New Orleans, New Orleans, Louisiana, United States of America
| | | | - Lori Stevens
- University of Vermont, Burlington, Vermont, United States of America
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Oliveira TDSFD, Santos BND, Galdino TS, Hasslocher-Moreno AM, Bastos OMP, Sousa MAD. Trypanosoma cruzi I genotype among isolates from patients with chronic Chagas disease followed at the Evandro Chagas National Institute of Infectious Diseases (FIOCRUZ, Brazil). Rev Soc Bras Med Trop 2017; 50:35-43. [PMID: 28327800 DOI: 10.1590/0037-8682-0406-2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 12/02/2016] [Indexed: 01/18/2023] Open
Abstract
INTRODUCTION: Trypanosoma cruzi is the etiologic agent of Chagas disease in humans, mainly in Latin America. Trypanosome stocks were isolated by hemoculture from patients followed at Evandro Chagas National Institute of Infectious Diseases (FIOCRUZ) and studied using different approaches. METHODS: For species and genotype identification, the stocks were analyzed by parasitological techniques, polymerase chain reaction assays targeted to specific DNA sequences, isoenzyme patterns, besides sequencing of a polymorphic locus of TcSC5D gene (one stock). RESULTS: The isolates presented typical T. cruzi morphology and usually grew well in routine culture media. Metacyclic trypomastigotes were found in cultures or experimentally infected Triatoma infestans. All isolates were pure T. cruzi cultures, presenting typical 330-bp products from kinetoplast DNA minicircles, and 250 or 200-bp amplicons from the mini-exon non-transcribed spacer. Their genetic type assignment was resolved by their isoenzyme profiles. The finding of TcI in one asymptomatic patient from Paraíba was confirmed by the sequencing assay. TcVI was found in two asymptomatic individuals from Bahia and Rio Grande do Sul. TcII was identified in six patients from Pernambuco, Bahia and Minas Gerais, who presented different clinical forms: cardiac (2), digestive with megaesophagus (1), and indeterminate (3). CONCLUSIONS: The main T. cruzi genotypes found in Brazilian chronic patients were identified in this work, including TcI, which is less frequent and usually causes asymptomatic disease, unlike that in other American countries. This study emphasizes the importance of T. cruzi genotyping for possible correlations between the parasite and patient' responses to therapeutic treatment or disease clinical manifestations.
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Affiliation(s)
| | | | - Tainah Silva Galdino
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
| | | | - Otilio Machado Pereira Bastos
- Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, RJ, Brasil
| | - Maria Auxiliadora de Sousa
- Coleção de Tripanossomatídeos, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.,Laboratório de Toxoplasmose e Outras Protozooses, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
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Ecology of Trypanosoma cruzi I genotypes across Rhodnius prolixus captured in Attalea butyracea palms. INFECTION GENETICS AND EVOLUTION 2017; 49:146-150. [DOI: 10.1016/j.meegid.2017.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/10/2017] [Accepted: 01/14/2017] [Indexed: 11/18/2022]
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Muñoz-San Martín C, Apt W, Zulantay I. Real-time PCR strategy for the identification of Trypanosoma cruzi discrete typing units directly in chronically infected human blood. INFECTION GENETICS AND EVOLUTION 2017; 49:300-308. [PMID: 28185987 DOI: 10.1016/j.meegid.2017.02.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 02/03/2017] [Accepted: 02/04/2017] [Indexed: 10/20/2022]
Abstract
The protozoan Trypanosoma cruzi is the causative agent of Chagas disease, a major public health problem in Latin America. This parasite has a complex population structure comprised by six or seven major evolutionary lineages (discrete typing units or DTUs) TcI-TcVI and TcBat, some of which have apparently resulted from ancient hybridization events. Because of the existence of significant biological differences between these lineages, strain characterization methods have been essential to study T. cruzi in its different vectors and hosts. However, available methods can be laborious and costly, limited in resolution or sensitivity. In this study, a new genotyping strategy by real-time PCR to identify each of the six DTUs in clinical blood samples have been developed and evaluated. Two nuclear (SL-IR and 18S rDNA) and two mitochondrial genes (COII and ND1) were selected to develop original primers. The method was evaluated with eight genomic DNA of T. cruzi populations belonging to the six DTUs, one genomic DNA of Trypanosoma rangeli, and 53 blood samples from individuals with chronic Chagas disease. The assays had an analytical sensitivity of 1-25fg of DNA per reaction tube depending on the DTU analyzed. The selectivity of trials with 20fg/μL of genomic DNA identified each DTU, excluding non-targets DTUs in every test. The method was able to characterize 67.9% of the chronically infected clinical samples with high detection of TcII followed by TcI. With the proposed original genotyping methodology, each DTU was established with high sensitivity after a single real-time PCR assay. This novel protocol reduces carryover contamination, enables detection of each DTU independently and in the future, the quantification of each DTU in clinical blood samples.
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Affiliation(s)
- Catalina Muñoz-San Martín
- Laboratorio de Parasitología Básico-Clínico, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Werner Apt
- Laboratorio de Parasitología Básico-Clínico, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Inés Zulantay
- Laboratorio de Parasitología Básico-Clínico, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
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Izeta-Alberdi A, Ibarra-Cerdeña CN, Moo-Llanes DA, Ramsey JM. Geographical, landscape and host associations of Trypanosoma cruzi DTUs and lineages. Parasit Vectors 2016; 9:631. [PMID: 27923409 PMCID: PMC5142175 DOI: 10.1186/s13071-016-1918-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/28/2016] [Indexed: 01/04/2023] Open
Abstract
Background The evolutionary history and ecological associations of Trypanosoma cruzi, the need to identify genetic markers that can distinguish parasite subpopulations, and understanding the parasite’s evolutionary and selective processes have been the subject of a significant number of publications since 1998, the year when the first DNA sequence analysis for the species was published. Methods The current analysis systematizes and re-analyzes this original research, focusing on critical methodological and analytical variables and results that have given rise to interpretations of putative patterns of genetic diversity and diversification of T. cruzi lineages, discrete typing units (DTUs), and populations, and their associations with hosts, vectors, and geographical distribution that have been interpreted as evidence for parasite subpopulation specificities. Results Few studies use hypothesis-driven or quantitative analysis for T. cruzi phylogeny (16/58 studies) or phylogeography (10/13). Among these, only one phylogenetic and five phylogeographic studies analyzed molecular markers directly from tissues (i.e. not from isolates). Analysis of T. cruzi DTU or lineage niche and its geographical projection demonstrate extensive sympatry among all clades across the continent and no significant niche differences among DTUs. DTU beta-diversity was high, indicating diverse host assemblages across regions, while host dissimilarity was principally due to host species turnover and to a much lesser degree to nestedness. DTU-host order specificities appear related to trophic or microenvironmental interactions. Conclusions More rigorous study designs and analyses will be required to discern evolutionary processes and the impact of landscape modification on population dynamics and risk for T. cruzi transmission to humans. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1918-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Carlos N Ibarra-Cerdeña
- Departamento de Ecología Humana, Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav) Unidad Mérida, Mérida, Yucatán, Mexico
| | - David A Moo-Llanes
- Centro Regional de Investigación en Salud Pública (CRISP), Instituto Nacional de Salud Pública (INSP), Tapachula, Chiapas, Mexico
| | - Janine M Ramsey
- Centro Regional de Investigación en Salud Pública (CRISP), Instituto Nacional de Salud Pública (INSP), Tapachula, Chiapas, Mexico.
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Hernández C, Salazar C, Brochero H, Teherán A, Buitrago LS, Vera M, Soto H, Florez-Rivadeneira Z, Ardila S, Parra-Henao G, Ramírez JD. Untangling the transmission dynamics of primary and secondary vectors of Trypanosoma cruzi in Colombia: parasite infection, feeding sources and discrete typing units. Parasit Vectors 2016; 9:620. [PMID: 27903288 PMCID: PMC5131512 DOI: 10.1186/s13071-016-1907-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 11/22/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trypanosoma cruzi is the causative agent of Chagas disease. Due to its genetic diversity has been classified into six Discrete Typing Units (DTUs) in association with transmission cycles. In Colombia, natural T. cruzi infection has been detected in 15 triatomine species. There is scarce information regarding the infection rates, DTUs and feeding preferences of secondary vectors. Therefore, the aim of this study was to determine T. cruzi infection rates, parasite DTU, ecotopes, insect stages, geographical location and bug feeding preferences across six different triatomine species. METHODS A total of 245 insects were collected in seven departments of Colombia. We conducted molecular detection and genotyping of T. cruzi with subsequent identification of food sources. The frequency of infection, DTUs, TcI genotypes and feeding sources were plotted across the six species studied. A logistic regression model risk was estimated with insects positive for T. cruzi according to demographic and eco-epidemiological characteristics. RESULTS We collected 85 specimens of Panstrongylus geniculatus, 77 Rhodnius prolixus, 37 R. pallescens, 34 Triatoma maculata, 8 R. pictipes and 4 T. dimidiata. The overall T. cruzi infection rate was 61.2% and presented statistical associations with the departments Meta (OR: 2.65; 95% CI: 1.69-4.17) and Guajira (OR: 2.13; 95% CI: 1.16-3.94); peridomestic ecotope (OR: 2.52: 95% CI: 1.62-3.93); the vector species P. geniculatus (OR: 2.40; 95% CI: 1.51-3.82) and T. maculata (OR: 2.09; 95% CI: 1.02-4.29); females (OR: 2.05; 95% CI: 1.39-3.04) and feeding on opossum (OR: 3.15; 95% CI: 1.85-11.69) and human blood (OR: 1.55; 95% CI: 1.07-2.24). Regarding the DTUs, we observed TcI (67.3%), TcII (6.7%), TcIII (8.7%), TcIV (4.0%) and TcV (6.0%). Across the samples typed as TcI, we detected TcIDom (19%) and sylvatic TcI (75%). The frequencies of feeding sources were 59.4% (human blood); 11.2% (hen); 9.6% (bat); 5.6% (opossum); 5.1% (mouse); 4.1% (dog); 3.0% (rodent); 1.0% (armadillo); and 1.0% (cow). CONCLUSIONS New scenarios of T. cruzi transmission caused by secondary and sylvatic vectors are considered. The findings of sylvatic DTUs from bugs collected in domestic and peridomestic ecotopes confirms the emerging transmission scenarios in Colombia.
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Affiliation(s)
- Carolina Hernández
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, 111221 Colombia
- Estudiante Doctoral, Doctorado Ciencias biomédicas y biológicas, Universidad el Rosario, Bogotá, Colombia
| | - Camilo Salazar
- Biology Program, Faculty of Natural Sciences and Mathematics, Universidad del Rosario, Carrera. 24 No. 63C-69, Bogotá, DC 111221 Colombia
| | - Helena Brochero
- Facultad de Ciencias Agrarias, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Aníbal Teherán
- Grupo de Investigación COMPLEXUS, Fundación Universitaria Juan N. Corpas, Bogotá, Colombia
| | | | - Mauricio Vera
- Ministerio de Salud y protección Social, Bogotá, Colombia
| | - Hugo Soto
- Laboratorio de Salud Pública del Cesar, Valledupar, Colombia
| | | | - Sussane Ardila
- Grupo de Entomología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Gabriel Parra-Henao
- Centro de Investigación en Salud para el Trópico, Universidad Cooperativa de Colombia, Santa Marta, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, 111221 Colombia
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Kerr CL, Bhattacharyya T, Xavier SCC, Barros JH, Lima VS, Jansen AM, Miles MA. Lineage-specific serology confirms Brazilian Atlantic forest lion tamarins, Leontopithecus chrysomelas and Leontopithecus rosalia, as reservoir hosts of Trypanosoma cruzi II (TcII). Parasit Vectors 2016; 9:584. [PMID: 27846858 PMCID: PMC5111205 DOI: 10.1186/s13071-016-1873-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 11/03/2016] [Indexed: 02/04/2023] Open
Abstract
Background Trypanosoma cruzi, the agent of Chagas disease in humans, has a vast reservoir of mammalian hosts in the Americas, and is classified into six genetic lineages, TcI-TcVI, with a possible seventh, TcBat. Elucidating enzootic cycles of the different lineages is important for understanding the ecology of this parasite, the emergence of new outbreaks of Chagas disease and for guiding control strategies. Direct lineage identification by genotyping is hampered by limitations of parasite isolation and culture. An indirect method is to identify lineage-specific serological reactions in infected individuals; here we describe its application with sylvatic Brazilian primates. Methods Synthetic peptides representing lineage-specific epitopes of the T. cruzi surface protein TSSA were used in ELISA with sera from Atlantic Forest Leontopithecus chrysomelas (golden-headed lion tamarin), L. rosalia (golden lion tamarin), Amazonian Sapajus libidinosus (black-striped capuchin) and Alouatta belzebul (red-handed howler monkey). Results The epitope common to lineages TcII, TcV and TcVI was recognised by sera from 15 of 26 L. chrysomelas and 8 of 13 L. rosalia. For 12 of these serologically identified TcII infections, the identity of the lineage infection was confirmed by genotyping T. cruzi isolates. Of the TcII/TcV/TcVI positive sera 12 of the 15 L. chrysomelas and 2 of the 8 L. rosalia also reacted with the specific epitope restricted to TcV and TcVI. Sera from one of six S. libidinous recognised the TcIV/TcIII epitopes. Conclusions This lineage-specific serological surveillance has verified that Atlantic Forest primates are reservoir hosts of at least TcII, and probably TcV and TcVI, commonly associated with severe Chagas disease in the southern cone region of South America. With appropriate reagents, this novel methodology is readily applicable to a wide range of mammal species and reservoir host discovery.
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Affiliation(s)
- Charlotte L Kerr
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, UK
| | - Tapan Bhattacharyya
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, UK.
| | - Samanta C C Xavier
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Av. Brasil 4365, Rio de Janeiro, RJ, Zip Code 21040-360, Brazil
| | - Juliana H Barros
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Av. Brasil 4365, Rio de Janeiro, RJ, Zip Code 21040-360, Brazil
| | - Valdirene S Lima
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Av. Brasil 4365, Rio de Janeiro, RJ, Zip Code 21040-360, Brazil
| | - Ana M Jansen
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, Fiocruz, Av. Brasil 4365, Rio de Janeiro, RJ, Zip Code 21040-360, Brazil
| | - Michael A Miles
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, UK
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Abstract
SUMMARYChagas disease is a complex zoonosis that affects around 8 million people worldwide. This pathology is caused byTrypanosoma cruzi, a kinetoplastid parasite that shows tremendous genetic diversity evinced in six distinct Discrete Typing Units (TcI-TcVI) including a recent genotype named as TcBat and associated with anthropogenic bats. TcI presents a broad geographical distribution and has been associated with chronic cardiomyopathy. Recent phylogenetic studies suggest the existence of two genotypes (Domestic (TcIDom) and sylvatic TcI) within TcI. The understanding of the course of the infection in different mouse models by these two genotypes is not yet known. Therefore, we infected 126 animals (ICR-CD1, National Institute of Health (NIH) and Balb/c) with two TcIDomstrains and one sylvatic strain for a follow-up period of 60 days. We quantified the parasitaemia, immune response and histopathology observing that the maximum day of parasitaemia was achieved at day 21 post-infection. Domestic strains showed higher parasitaemia than the sylvatic strain in the three mouse models; however in the survival curves Balb/c mice were less susceptible to infection compared with NIH and ICR-CD1. Our results suggest that the genetic background plays a fundamental role in the natural history of the infection and the sympatric TcI genotypes have relevant implications in disease pathogenesis.
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Hernández C, Cucunubá Z, Flórez C, Olivera M, Valencia C, Zambrano P, León C, Ramírez JD. Molecular Diagnosis of Chagas Disease in Colombia: Parasitic Loads and Discrete Typing Units in Patients from Acute and Chronic Phases. PLoS Negl Trop Dis 2016; 10:e0004997. [PMID: 27648938 PMCID: PMC5029947 DOI: 10.1371/journal.pntd.0004997] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 08/22/2016] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The diagnosis of Chagas disease is complex due to the dynamics of parasitemia in the clinical phases of the disease. The molecular tests have been considered promissory because they detect the parasite in all clinical phases. Trypanosoma cruzi presents significant genetic variability and is classified into six Discrete Typing Units TcI-TcVI (DTUs) with the emergence of foreseen genotypes within TcI as TcIDom and TcI Sylvatic. The objective of this study was to determine the operating characteristics of molecular tests (conventional and Real Time PCR) for the detection of T. cruzi DNA, parasitic loads and DTUs in a large cohort of Colombian patients from acute and chronic phases. METHODOLOGY/PRINCIPAL FINDINGS Samples were obtained from 708 patients in all clinical phases. Standard diagnosis (direct and serological tests) and molecular tests (conventional PCR and quantitative PCR) targeting the nuclear satellite DNA region. The genotyping was performed by PCR using the intergenic region of the mini-exon gene, the 24Sa, 18S and A10 regions. The operating capabilities showed that performance of qPCR was higher compared to cPCR. Likewise, the performance of qPCR was significantly higher in acute phase compared with chronic phase. The median parasitic loads detected were 4.69 and 1.33 parasite equivalents/mL for acute and chronic phases. The main DTU identified was TcI (74.2%). TcIDom genotype was significantly more frequent in chronic phase compared to acute phase (82.1% vs 16.6%). The median parasitic load for TcIDom was significantly higher compared with TcI Sylvatic in chronic phase (2.58 vs.0.75 parasite equivalents/ml). CONCLUSIONS/SIGNIFICANCE The molecular tests are a precise tool to complement the standard diagnosis of Chagas disease, specifically in acute phase showing high discriminative power. However, it is necessary to improve the sensitivity of molecular tests in chronic phase. The frequency and parasitemia of TcIDom genotype in chronic patients highlight its possible relationship to the chronicity of the disease.
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Affiliation(s)
- Carolina Hernández
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Zulma Cucunubá
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Carolina Flórez
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Mario Olivera
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Carlos Valencia
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Pilar Zambrano
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Cielo León
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad el Rosario, Bogotá, Colombia
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Barnabé C, Mobarec HI, Jurado MR, Cortez JA, Brenière SF. Reconsideration of the seven discrete typing units within the species Trypanosoma cruzi , a new proposal of three reliable mitochondrial clades. INFECTION GENETICS AND EVOLUTION 2016; 39:176-186. [DOI: 10.1016/j.meegid.2016.01.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 01/29/2016] [Accepted: 01/30/2016] [Indexed: 10/22/2022]
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Shender LA, Lewis MD, Rejmanek D, Mazet JAK. Molecular Diversity of Trypanosoma cruzi Detected in the Vector Triatoma protracta from California, USA. PLoS Negl Trop Dis 2016; 10:e0004291. [PMID: 26797311 PMCID: PMC4721664 DOI: 10.1371/journal.pntd.0004291] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 11/19/2015] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Trypanosoma cruzi, causative agent of Chagas disease in humans and dogs, is a vector-borne zoonotic protozoan parasite that can cause fatal cardiac disease. While recognized as the most economically important parasitic infection in Latin America, the incidence of Chagas disease in the United States of America (US) may be underreported and even increasing. The extensive genetic diversity of T. cruzi in Latin America is well-documented and likely influences disease progression, severity and treatment efficacy; however, little is known regarding T. cruzi strains endemic to the US. It is therefore important to expand our knowledge on US T. cruzi strains, to improve upon the recognition of and response to locally acquired infections. METHODOLOGY/PRINCIPLE FINDINGS We conducted a study of T. cruzi molecular diversity in California, augmenting sparse genetic data from southern California and for the first time investigating genetic sequences from northern California. The vector Triatoma protracta was collected from southern (Escondido and Los Angeles) and northern (Vallecito) California regions. Samples were initially screened via sensitive nuclear repetitive DNA and kinetoplast minicircle DNA PCR assays, yielding an overall prevalence of approximately 28% and 55% for southern and northern California regions, respectively. Positive samples were further processed to identify discrete typing units (DTUs), revealing both TcI and TcIV lineages in southern California, but only TcI in northern California. Phylogenetic analyses (targeting COII-ND1, TR and RB19 genes) were performed on a subset of positive samples to compare Californian T. cruzi samples to strains from other US regions and Latin America. Results indicated that within the TcI DTU, California sequences were similar to those from the southeastern US, as well as to several isolates from Latin America responsible for causing Chagas disease in humans. CONCLUSIONS/SIGNIFICANCE Triatoma protracta populations in California are frequently infected with T. cruzi. Our data extend the northern limits of the range of TcI and identify a novel genetic exchange event between TcI and TcIV. High similarity between sequences from California and specific Latin American strains indicates US strains may be equally capable of causing human disease. Additional genetic characterization of Californian and other US T. cruzi strains is recommended.
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Affiliation(s)
- Lisa A. Shender
- Wildlife Health Center; One Health Institute; School of Veterinary Medicine, University of California, Davis, Davis, California, United States of America
- * E-mail:
| | - Michael D. Lewis
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Daniel Rejmanek
- Wildlife Health Center; One Health Institute; School of Veterinary Medicine, University of California, Davis, Davis, California, United States of America
| | - Jonna A. K. Mazet
- Wildlife Health Center; One Health Institute; School of Veterinary Medicine, University of California, Davis, Davis, California, United States of America
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Cardoso MS, Reis-Cunha JL, Bartholomeu DC. Evasion of the Immune Response by Trypanosoma cruzi during Acute Infection. Front Immunol 2016; 6:659. [PMID: 26834737 PMCID: PMC4716143 DOI: 10.3389/fimmu.2015.00659] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 12/24/2015] [Indexed: 12/11/2022] Open
Abstract
Trypanosoma cruzi is the etiologic agent of Chagas disease, a neglected tropical disease that affects millions of people mainly in Latin America. To establish a life-long infection, T. cruzi must subvert the vertebrate host's immune system, using strategies that can be traced to the parasite's life cycle. Once inside the vertebrate host, metacyclic trypomastigotes rapidly invade a wide variety of nucleated host cells in a membrane-bound compartment known as the parasitophorous vacuole, which fuses to lysosomes, originating the phagolysosome. In this compartment, the parasite relies on a complex network of antioxidant enzymes to shield itself from lysosomal oxygen and nitrogen reactive species. Lysosomal acidification of the parasitophorous vacuole is an important factor that allows trypomastigote escape from the extremely oxidative environment of the phagolysosome to the cytoplasm, where it differentiates into amastigote forms. In the cytosol of infected macrophages, oxidative stress instead of being detrimental to the parasite, favors amastigote burden, which then differentiates into bloodstream trypomastigotes. Trypomastigotes released in the bloodstream upon the rupture of the host cell membrane express surface molecules, such as calreticulin and GP160 proteins, which disrupt initial and key components of the complement pathway, while others such as glycosylphosphatidylinositol-mucins stimulate immunoregulatory receptors, delaying the progression of a protective immune response. After an immunologically silent entry at the early phase of infection, T. cruzi elicits polyclonal B cell activation, hypergammaglobulinemia, and unspecific anti-T. cruzi antibodies, which are inefficient in controlling the infection. Additionally, the coexpression of several related, but not identical, epitopes derived from trypomastigote surface proteins delays the generation of T. cruzi-specific neutralizing antibodies. Later in the infection, the establishment of an anti-T. cruzi CD8(+) immune response focused on the parasite's immunodominant epitopes controls parasitemia and tissue infection, but fails to completely eliminate the parasite. This outcome is not detrimental to the parasite, as it reduces host mortality and maintains the parasite infectivity toward the insect vectors.
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Affiliation(s)
- Mariana S Cardoso
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais, Brazil
| | - João Luís Reis-Cunha
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais, Brazil
| | - Daniella C Bartholomeu
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais, Brazil
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Molecular Approaches for Diagnosis of Chagas' Disease and Genotyping of Trypanosoma cruzi. Mol Microbiol 2016. [DOI: 10.1128/9781555819071.ch36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Messenger LA, Miles MA. Evidence and importance of genetic exchange among field populations of Trypanosoma cruzi. Acta Trop 2015; 151:150-5. [PMID: 26188331 PMCID: PMC4644990 DOI: 10.1016/j.actatropica.2015.05.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 04/25/2015] [Accepted: 05/06/2015] [Indexed: 10/31/2022]
Abstract
Many eukaryotic pathogenic microorganisms that were previously assumed to propagate clonally have retained cryptic sexual cycles. The principal reproductive mode of Trypanosoma cruzi, the aetiological agent of Chagas disease, remains a controversial topic. Despite the existence of two recent natural hybrid lineages, a pervasive view is that recombination has been restrained at an evolutionary scale and is of little epidemiological relevance to contemporary parasite populations. This article reviews the growing number of field studies which indicate that natural hybridization in T. cruzi may be frequent, non-obligatory and idiosyncratic; potentially involving independent exchange of kinetoplast and nuclear genetic material as well as canonical meiotic mechanisms. Together these observations now challenge the traditional paradigm of preponderate clonal evolution in T. cruzi and highlight the need for additional, intensive and appropriately sampled field surveys, complemented by high resolution, combined nuclear and mitochondrial population genetics analyses.
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Pennington PM, Messenger LA, Reina J, Juárez JG, Lawrence GG, Dotson EM, Llewellyn MS, Cordón-Rosales C. The Chagas disease domestic transmission cycle in Guatemala: Parasite-vector switches and lack of mitochondrial co-diversification between Triatoma dimidiata and Trypanosoma cruzi subpopulations suggest non-vectorial parasite dispersal across the Motagua valley. Acta Trop 2015. [PMID: 26215126 DOI: 10.1016/j.actatropica.2015.07.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Parasites transmitted by insects must adapt to their vectors and reservoirs. Chagas disease, an American zoonosis caused by Trypanosoma cruzi, is transmitted by several species of triatomines. In Central America, Triatoma dimidiata is a widely dispersed vector found in sylvatic and domestic habitats, with distinct populations across the endemic region of Guatemala. Our aim was to test the strength of association between vector and parasite genetic divergence in domestic environments. Microsatellite (MS) loci were used to characterize parasites isolated from T. dimidiata (n=112) collected in domestic environments. Moderate genetic differentiation was observed between parasites north and south of the Motagua Valley, an ancient biogeographic barrier (FST 0.138, p=0.009). Slightly reduced genotypic diversity and increased heterozygosity in the north (Allelic richness (Ar)=1.00-6.05, FIS -0.03) compared to the south (Ar=1.47-6.30, FIS 0.022) suggest either a selective or demographic process during parasite dispersal. Based on parasite genotypes and geographic distribution, 15 vector specimens and their parasite isolates were selected for mitochondrial co-diversification analysis. Genetic variability and phylogenetic congruence were determined with mitochondrial DNA sequences (10 parasite maxicircle gene fragments and triatomine ND4+CYT b). A Mantel test as well as phylogenetic, network and principal coordinates analyses supported at least three T. dimidiata haplogroups separated by geographic distance across the Motagua Valley. Maxicircle sequences showed low T. cruzi genetic variability (π nucleotide diversity 0.00098) with no evidence of co-diversification with the vector, having multiple host switches across the valley. Sylvatic Didelphis marsupialis captured across the Motagua Valley were found to be infected with T. cruzi strains sharing MS genotypes with parasites isolated from domiciliated triatomines. The current parasite distribution in domestic environments can be explained by multiple parasite-host switches between vector populations and selection or bottleneck processes across the Motagua Valley, with a possible role for didelphids in domestic transmission.
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Affiliation(s)
- Pamela M Pennington
- Universidad del Valle de Guatemala, Centro de Estudios en Salud, 18 Avenida 11-95 Z. 15 VH III, Guatemala, Guatemala.
| | - Louisa Alexandra Messenger
- London School of Hygiene & Tropical Medicine (University of London), Department of Infectious and Tropical Diseases, Keppel Street, London WC1E 7HT, UK
| | - Jeffrey Reina
- Universidad del Valle de Guatemala, Centro de Estudios en Salud, 18 Avenida 11-95 Z. 15 VH III, Guatemala, Guatemala
| | - José G Juárez
- Universidad del Valle de Guatemala, Centro de Estudios en Salud, 18 Avenida 11-95 Z. 15 VH III, Guatemala, Guatemala
| | - Gena G Lawrence
- Centers for Disease Control and Prevention. Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Atlanta, GA 30333, USA
| | - Ellen M Dotson
- Centers for Disease Control and Prevention. Division of Parasitic Diseases and Malaria, 1600 Clifton Rd, Atlanta, GA 30333, USA
| | - Martin S Llewellyn
- Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences,University of Wales, Bangor, Deiniol Road, Bangor, Gwynedd, LL57 2UW, UK
| | - Celia Cordón-Rosales
- Universidad del Valle de Guatemala, Centro de Estudios en Salud, 18 Avenida 11-95 Z. 15 VH III, Guatemala, Guatemala.
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Costales JA, Kotton CN, Zurita-Leal AC, Garcia-Perez J, Llewellyn MS, Messenger LA, Bhattacharyya T, Burleigh BA. Chagas disease reactivation in a heart transplant patient infected by domestic Trypanosoma cruzi discrete typing unit I (TcIDOM). Parasit Vectors 2015; 8:435. [PMID: 26303927 PMCID: PMC4548706 DOI: 10.1186/s13071-015-1039-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 08/10/2015] [Indexed: 01/31/2023] Open
Abstract
Background Trypanosoma cruzi, causative agent of Chagas disease, displays high intraspecific genetic diversity: six genetic lineages or discrete typing units (DTUs) are currently recognized, termed TcI through TcVI. Each DTU presents a particular distribution pattern across the Americas, and is loosely associated with different transmission cycles and hosts. Several DTUs are known to circulate in Central America. It has been previously suggested that TcI infection is benign and does not lead to chronic chagasic cardiomyopathy (CCC). Findings In this study, we genotyped T. cruzi parasites circulating in the blood and from explanted cardiac tissue of an El Salvadorian patient who developed reactivation Chagas disease while on immunosuppressive medications after undergoing heart transplant in the U.S. as treatment for end-stage CCC. Parasite typing was performed through molecular methods (restriction fragment length polymorphism of polymerase reaction chain amplified products, microsatellite typing, maxicircle sequence typing and low-stringency single primer PCR, [LSSP-PCR]) as well as lineage-specific serology. We show that the parasites infecting the patient belong to the TcI DTU exclusively. Our data indicate that the parasites isolated from the patient belong to a genotype frequently associated with human infection throughout the Americas (TcIDOM). Conclusions Our results constitute compelling evidence in support of TcI DTU’s ability to cause end-stage CCC and help dispel any residual bias that infection with this lineage is benign, pointing to the need for increased surveillance for dissemination of this genotype in endemic regions, the USA and globally.
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Affiliation(s)
- Jaime A Costales
- Centro de Investigación en Enfermedades Infecciosas, Escuela de Biología, Pontificia Universidad Católica del Ecuador, Avenida 12 de Octubre y Roca, Quito, Ecuador.
| | - Camille N Kotton
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, USA.
| | - Andrea C Zurita-Leal
- Centro de Investigación en Enfermedades Infecciosas, Escuela de Biología, Pontificia Universidad Católica del Ecuador, Avenida 12 de Octubre y Roca, Quito, Ecuador. .,Present address: Wellcome Trust Centre for Molecular Parasitology, Institute of Infection and Inflammation, College of Medical, Veterinary and Life Science, University of Glasgow, Glasgow, UK.
| | - Josselyn Garcia-Perez
- Centro de Investigación en Enfermedades Infecciosas, Escuela de Biología, Pontificia Universidad Católica del Ecuador, Avenida 12 de Octubre y Roca, Quito, Ecuador. .,Present address: VIB Autoimmune Genetics Laboratory, Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium.
| | - Martin S Llewellyn
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK. .,Present address: Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, University of Wales, Bangor, Deiniol Road, Bangor, Gwynedd, LL57 2UW, UK.
| | - Louisa A Messenger
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK.
| | - Tapan Bhattacharyya
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK.
| | - Barbara A Burleigh
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, USA.
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Messenger LA, Miles MA, Bern C. Between a bug and a hard place: Trypanosoma cruzi genetic diversity and the clinical outcomes of Chagas disease. Expert Rev Anti Infect Ther 2015; 13:995-1029. [PMID: 26162928 PMCID: PMC4784490 DOI: 10.1586/14787210.2015.1056158] [Citation(s) in RCA: 134] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Over the last 30 years, concomitant with successful transnational disease control programs across Latin America, Chagas disease has expanded from a neglected, endemic parasitic infection of the rural poor to an urbanized chronic disease, and now a potentially emergent global health problem. Trypanosoma cruzi infection has a highly variable clinical course, ranging from complete absence of symptoms to severe and often fatal cardiovascular and/or gastrointestinal manifestations. To date, few correlates of clinical disease progression have been identified. Elucidating a putative role for T. cruzi strain diversity in Chagas disease pathogenesis is complicated by the scarcity of parasites in clinical specimens and the limitations of our contemporary genotyping techniques. This article systematically reviews the historical literature, given our current understanding of parasite genetic diversity, to evaluate the evidence for any association between T. cruzi genotype and chronic clinical outcome, risk of congenital transmission or reactivation and orally transmitted outbreaks.
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Affiliation(s)
- Louisa A Messenger
- Department of Pathogen Molecular Biology, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Michael A Miles
- Department of Pathogen Molecular Biology, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Caryn Bern
- Global Health Sciences, Department of Epidemiology and Biostatistics, School of Medicine, University of California San Francisco, San Francisco, CA, USA
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Messenger LA, Garcia L, Vanhove M, Huaranca C, Bustamante M, Torrico M, Torrico F, Miles MA, Llewellyn MS. Ecological host fitting of Trypanosoma cruzi TcI in Bolivia: mosaic population structure, hybridization and a role for humans in Andean parasite dispersal. Mol Ecol 2015; 24:2406-22. [PMID: 25847086 PMCID: PMC4737126 DOI: 10.1111/mec.13186] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 03/02/2015] [Accepted: 03/13/2015] [Indexed: 01/04/2023]
Abstract
An improved understanding of how a parasite species exploits its genetic repertoire to colonize novel hosts and environmental niches is crucial to establish the epidemiological risk associated with emergent pathogenic genotypes. Trypanosoma cruzi, a genetically heterogeneous, multi-host zoonosis, provides an ideal system to examine the sylvatic diversification of parasitic protozoa. In Bolivia, T. cruzi I, the oldest and most widespread genetic lineage, is pervasive across a range of ecological clines. High-resolution nuclear (26 loci) and mitochondrial (10 loci) genotyping of 199 contemporaneous sylvatic TcI clones was undertaken to provide insights into the biogeographical basis of T. cruzi evolution. Three distinct sylvatic parasite transmission cycles were identified: one highland population among terrestrial rodent and triatomine species, composed of genetically homogenous strains (Ar = 2.95; PA/L = 0.61; DAS = 0.151), and two highly diverse, parasite assemblages circulating among predominantly arboreal mammals and vectors in the lowlands (Ar = 3.40 and 3.93; PA/L = 1.12 and 0.60; DAS = 0.425 and 0.311, respectively). Very limited gene flow between neighbouring terrestrial highland and arboreal lowland areas (distance ~220 km; FST = 0.42 and 0.35) but strong connectivity between ecologically similar but geographically disparate terrestrial highland ecotopes (distance >465 km; FST = 0.016-0.084) strongly supports ecological host fitting as the predominant mechanism of parasite diversification. Dissimilar heterozygosity estimates (excess in highlands, deficit in lowlands) and mitochondrial introgression among lowland strains may indicate fundamental differences in mating strategies between populations. Finally, accelerated parasite dissemination between densely populated, highland areas, compared to uninhabited lowland foci, likely reflects passive, long-range anthroponotic dispersal. The impact of humans on the risk of epizootic Chagas disease transmission in Bolivia is discussed.
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Affiliation(s)
- Louisa A. Messenger
- Department of Pathogen Molecular BiologyFaculty of Infectious and Tropical DiseasesLondon School of Hygiene and Tropical MedicineLondonUK
| | - Lineth Garcia
- Institute of Biomedical ResearchUniversidad Mayor de San SimónCochabambaBolivia
| | - Mathieu Vanhove
- Department of Infectious Disease EpidemiologyImperial College LondonLondonUK
| | - Carlos Huaranca
- Institute of Biomedical ResearchUniversidad Mayor de San SimónCochabambaBolivia
| | - Marinely Bustamante
- Institute of Biomedical ResearchUniversidad Mayor de San SimónCochabambaBolivia
| | - Marycruz Torrico
- Institute of Biomedical ResearchUniversidad Mayor de San SimónCochabambaBolivia
| | - Faustino Torrico
- Institute of Biomedical ResearchUniversidad Mayor de San SimónCochabambaBolivia
| | - Michael A. Miles
- Department of Pathogen Molecular BiologyFaculty of Infectious and Tropical DiseasesLondon School of Hygiene and Tropical MedicineLondonUK
| | - Martin S. Llewellyn
- Department of Pathogen Molecular BiologyFaculty of Infectious and Tropical DiseasesLondon School of Hygiene and Tropical MedicineLondonUK
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León CM, Hernández C, Montilla M, Ramírez JD. Retrospective distribution of Trypanosoma cruzi I genotypes in Colombia. Mem Inst Oswaldo Cruz 2015; 110:387-93. [PMID: 25946157 PMCID: PMC4489476 DOI: 10.1590/0074-02760140402] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 02/25/2015] [Indexed: 12/03/2022] Open
Abstract
Trypanosoma cruzi is the aetiological agent of Chagas disease, which
affects approximately eight million people in the Americas. This parasite exhibits
genetic variability, with at least six discrete typing units broadly distributed in
the American continent. T. cruzi I (TcI) shows remarkable genetic
diversity; a genotype linked to human infections and a domestic cycle of transmission
have recently been identified, hence, this strain was named TcIDom. The aim of this
work was to describe the spatiotemporal distribution of TcI subpopulations across
humans, insect vectors and mammalian reservoirs in Colombia by means of molecular
typing targeting the spliced leader intergenic region of mini-exon gene. We analysed
101 TcI isolates and observed a distribution of sylvatic TcI in 70% and TcIDom in
30%. In humans, the ratio was sylvatic TcI in 60% and TcIDom in 40%. In mammal
reservoirs, the distribution corresponded to sylvatic TcI in 96% and TcIDom in 4%.
Among insect vectors, sylvatic TcI was observed in 48% and TcIDom in 52%. In
conclusion, the circulation of TcIDom is emerging in Colombia and this genotype is
still adapting to the domestic cycle of transmission. The epidemiological and
clinical implications of these findings are discussed herein.
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Affiliation(s)
- Cielo M León
- Red Chagas Colombia, Instituto Nacional de Salud, Bogotá, Colombia
| | | | - Marleny Montilla
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
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Cruz L, Vivas A, Montilla M, Hernández C, Flórez C, Parra E, Ramírez JD. Comparative study of the biological properties of Trypanosoma cruzi I genotypes in a murine experimental model. INFECTION GENETICS AND EVOLUTION 2015; 29:110-7. [DOI: 10.1016/j.meegid.2014.11.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/10/2014] [Accepted: 11/12/2014] [Indexed: 11/27/2022]
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Tomasini N, Lauthier JJ, Monje Rumi MM, Ragone PG, Alberti D'Amato AM, Brandán CP, Basombrío MA, Diosque P. Preponderant clonal evolution of Trypanosoma cruzi I from Argentinean Chaco revealed by Multilocus Sequence Typing (MLST). INFECTION GENETICS AND EVOLUTION 2014; 27:348-54. [PMID: 25111612 DOI: 10.1016/j.meegid.2014.08.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 08/01/2014] [Accepted: 08/02/2014] [Indexed: 10/24/2022]
Abstract
Trypanosoma cruzi has been historically classified as a species with preponderant clonal evolution (PCE). However, with the advent of highly polymorphic markers and studies at geographically reduced scales, the PCE in T. cruzi was challenged. In fact, some studies have suggested that recombination in T. cruzi lineage I (TcI) is much more frequent than previously believed. Further analyses of TcI populations from different geographical regions of Latin America are needed to examine this hypothesis. In the present study, we contribute to this topic by analyzing the population structure of TcI from a restricted geographical area in the Chaco region, Argentina. We analyzed TcI isolates from different hosts and vectors using a Multilocus Sequence Typing (MLST) approach. These isolates were previously characterized by sequencing the spliced leader intergenic region (SL-IR). Low levels of incongruence and well-supported clusters for MLST dataset were obtained from the analyses. Moreover, high linkage disequilibrium was found and five repeated and overrepresented genotypes were detected. In addition, a good correspondence between SL-IR and MLST was observed which is expected under PCE. However, recombination is not ruled out because five out of 28 pairs of loci were incompatible with strict clonality and one possible genetic exchange event was detected. Overall, our results represent evidence of PCE in TcI from the study area. Finally, considering our findings we discuss the scenario for the genetic structure of TcI.
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Affiliation(s)
- Nicolás Tomasini
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina.
| | - Juan J Lauthier
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina.
| | - María M Monje Rumi
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina
| | - Paula G Ragone
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina
| | - Anahí M Alberti D'Amato
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina
| | - Cecilia Pérez Brandán
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina
| | - Miguel A Basombrío
- Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina
| | - Patricio Diosque
- Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina; Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400 Salta, Argentina
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Monteón V, Triana-Chávez O, Mejía-Jaramillo A, Pennignton P, Ramos-Ligonio Á, Acosta K, Lopez R. Circulation of Tc Ia discrete type unit Trypanosoma cruzi in Yucatan Mexico. J Parasit Dis 2014; 40:550-4. [PMID: 27413339 DOI: 10.1007/s12639-014-0499-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 06/24/2014] [Indexed: 01/04/2023] Open
Abstract
The etiologic agent Trypanosoma cruzi (Tc) has been grouped into six discrete type units (DTU I-VI); within DTU-I exists four subgroups defined Ia-Id. In Colombia, the genotype Ia is associated with human infection and domiciliated Rhodnius vector. In the Yucatan Peninsula of Mexico, the main vector involved in T. cruzi transmission is Triatoma dimidiata predominantly via sylvatic and peridomiciliated cycles. In this study, multiple sequence analysis of mini-exon intergenic regions of T. cruzi isolates obtained from T. dimidiata in the Yucatan Peninsula of Mexico revealed they belonged to Tc Ia DTU along with two additional Mexican strains located 1,570 km away from Yucatan. In conclusion Tc Ia circulates in the Yucatan peninsula in T. dimidiata vector and likewise in the northwest region of Mexico.
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Affiliation(s)
- Victor Monteón
- Centro de Investigaciones Biomédicas, Universidad Autónoma de Campeche, Campus de la Salud, Col Linda Vista Campeche, 24090 Campeche, Mexico
| | - Omar Triana-Chávez
- Grupo Biología y Control de Enfermedades Infecciosas (BCEI), Universidad de Antioquia, Medellín, Colombia
| | - Ana Mejía-Jaramillo
- Grupo Biología y Control de Enfermedades Infecciosas (BCEI), Universidad de Antioquia, Medellín, Colombia
| | - Pamela Pennignton
- Center for Health Studies, Universidad del Valle de Guatemala, Guatemala City, Guatemala
| | - Ángel Ramos-Ligonio
- Laboratorio de Investigación y Servicios (LADASIER) Inmunología y Biología Molecular, Universidad Veracruzana, Orizaba, Veracruz Mexico
| | - Karla Acosta
- Centro Regional de Investigaciones Biomédicas "Hideyo Noguchi", Mérida, Yucatán Mexico
| | - Ruth Lopez
- Centro de Investigaciones Biomédicas, Universidad Autónoma de Campeche, Campus de la Salud, Col Linda Vista Campeche, 24090 Campeche, Mexico
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Santana RAG, Magalhães LKC, Magalhães LKC, Prestes SR, Maciel MG, da Silva GAV, Monteiro WM, de Brito FR, de Aguiar Raposo Câmara Coelho LI, Barbosa-Ferreira JM, Guerra JAO, Silveira H, das Graças Vale Barbosa M. Trypanosoma cruzi strain TcI is associated with chronic Chagas disease in the Brazilian Amazon. Parasit Vectors 2014; 7:267. [PMID: 24916362 PMCID: PMC4072607 DOI: 10.1186/1756-3305-7-267] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 05/31/2014] [Indexed: 12/19/2022] Open
Abstract
Background Chagas disease in the Amazon region is considered an emerging anthropozoonosis with a predominance of the discrete typing units (DTUs) TcI and TcIV. These DTUs are responsible for cases of acute disease associated with oral transmission. Chronic disease cases have been detected through serological surveys. However, the mode of transmission could not be determined, or any association of chronic disease with a specific T. cruzi DTU’s. The aim of this study was to characterize Trypanosoma cruzi in patients with chronic Chagas disease in the State of Amazonas, Brazil. Methods Blood culture and xenodiagnosis were performed in 36 patients with positive serology for Chagas disease who participated in a serological survey performed in urban and rural areas of Manaus, Amazonas. DNA samples were extracted from the feces of triatomines used for xenodiagnosis, and the nontranscribed spacer of the mini-exon gene and the mitochondrial gene cytochrome oxidase subunit II (COII) were amplified by PCR and sequenced. Results Blood culture and xenodiagnosis were negative in 100% of samples; however, molecular techniques revealed that in 13 out of 36 (36%) fecal samples from xenodiagnosis, T. cruzi was characterized as the DTU TcI, and different haplotypes were identified within the same DTU. Conclusion The DTU TcI, which is mainly associated with acute cases of Chagas disease in the Amazon region, is also responsible for chronic infection in patients from a region in the State of Amazonas.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Henrique Silveira
- Institute of Hygiene and Tropical Medicine (Instituto de Higiene e Medicina Tropical), New University of Lisbon (Universidade Nova de Lisboa), Lisbon, Portugal.
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de Sá ARN, Steindel M, Demeu LMK, Lückemeyer DD, Grisard EC, Neto QADL, de Araújo SM, Toledo MJDO, Gomes ML. Cytochrome oxidase subunit 2 gene allows simultaneous detection and typing of Trypanosoma rangeli and Trypanosoma cruzi. Parasit Vectors 2013; 6:363. [PMID: 24360167 PMCID: PMC3891993 DOI: 10.1186/1756-3305-6-363] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 12/18/2013] [Indexed: 11/18/2022] Open
Abstract
Background The parasites Trypanosoma rangeli and Trypanosoma cruzi share vectors and hosts over a wide geographical area in Latin America. In this study, we propose a single molecular approach for simultaneous detection and typing of T. rangeli and T. cruzi. Methods A restriction fragment length polymorphism analysis of the mitochondrial cytochrome oxidase II gene (COII-RFLP) using enzyme AluI and different amounts of DNA from the major genetic groups of T. rangeli and T. cruzi (KP1+/KP1- and DTU-I/DTU-II) was carried out. The same marker was tested on the other T. cruzi DTUs (DTU-III to DTU-VI) and on DNA extracted from gut contents of experimentally infected triatomines. Results The COII PCR generates a ~400 bp fragment, which after digestion with AluI (COII-RFLP) can be used to distinguish T. rangeli from T. cruzi and simultaneously differentiate the major genetic groups of T. rangeli (KP1+ and KP1-) and T. cruzi (DTU-I and DTU-II). The COII-RFLP generated bands of ~120 bp and ~280 bp for KP1+, whereas for KP1- no amplicon cleavage was observed. For T. cruzi, digestion of COII revealed a ~300 bp band for DTU-I and a ~250 bp band for DTU-II. For DTU-III to DTU-VI, COII-RFLP generated bands ranging from ~310 to ~330 bp, but the differentiation of these DTUs was not as clear as the separation between DTU-I and DTU-II. After AluI digestion, a species-specific fragment of ~80 bp was observed for all DTUs of T. cruzi. No cross-amplification was observed for Leishmania spp., T. vivax or T. evansi. Conclusions The COII-RFLP allowed simultaneous detection and typing of T. rangeli and T. cruzi strains according to their major genetic groups (KP1+/KP1- and DTU-I/DTU-II) in vitro and in vivo, providing a reliable and sensitive tool for epidemiological studies in areas where T. rangeli and T. cruzi coexist.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Mônica Lúcia Gomes
- Departamento de Ciências Básicas da Saúde, Universidade Estadual de Maringá (UEM), Av, Colombo, 5790, Zona 7, CEP: 87020-900, Maringá, Paraná, Brazil.
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Retrospective molecular integrated epidemiology of Chagas disease in Colombia. INFECTION GENETICS AND EVOLUTION 2013; 20:148-54. [DOI: 10.1016/j.meegid.2013.08.028] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 08/27/2013] [Accepted: 08/28/2013] [Indexed: 11/17/2022]
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Roellig DM, Savage MY, Fujita AW, Barnabé C, Tibayrenc M, Steurer FJ, Yabsley MJ. Genetic variation and exchange in Trypanosoma cruzi isolates from the United States. PLoS One 2013; 8:e56198. [PMID: 23457528 PMCID: PMC3572986 DOI: 10.1371/journal.pone.0056198] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 01/10/2013] [Indexed: 12/22/2022] Open
Abstract
Trypanosoma cruzi, the causative agent of Chagas disease, is a multiclonal parasite with high levels of genetic diversity and broad host and geographic ranges. Molecular characterization of South American isolates of T. cruzi has demonstrated homologous recombination and nuclear hybridization, as well as the presence of 6 main genetic clusters or "discrete typing units" (DTUs). Few studies have extensively investigated such exchange events and genetic diversity in North American isolates. In the current study, we genetically characterized over 50 US isolates from wildlife reservoirs (e.g., raccoons, opossums, armadillos, skunks), domestic dogs, humans, nonhuman primates, and reduviid vectors from nine states (TX, CA, OK, SC, FL, GA, MD, LA, TN) using a multilocus sequencing method. Single nucleotide polymorphisms were identified in sequences of the mismatch-repair class 2 (MSH2) and Tc52 genes. Typing based on the two genes often paralleled genotyping by classic methodologies using mini-exon and 18S and 24Sα rRNA genes. Evidence for genetic exchange was obtained by comparing sequence phylogenies of nuclear and mitochondrial gene targets, dihydrofolate reductase-thymidylate synthase (DHFR-TS) and the cytochrome oxidase subunit II- NADH dehydrogenase subunit I region (COII-ND1), respectively. We observed genetic exchange in several US isolates as demonstrated by incongruent mitochondrial and nuclear genes phylogenies, which confirms a previous finding of a single genetic exchange event in a Florida isolate. The presence of SNPs and evidence of genetic exchange illustrates that strains from the US are genetically diverse, even though only two phylogenetic lineages have been identified in this region.
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Affiliation(s)
- Dawn M Roellig
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America.
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