Small subunit ribosomal metabarcoding reveals extraordinary trypanosomatid diversity in Brazilian bats

Background: Bats are a highly successful, globally dispersed order of mammals that occupy a wide array of ecological niches. They are also intensely parasitized and implicated in multiple viral, bacterial and parasitic zoonoses. Trypanosomes are thought to be especially abundant and diverse in bats. In this study, we used 18S ribosomal RNA metabarcoding to probe bat trypanosome diversity in unprecedented detail. Methodology/Principal Findings: Total DNA was extracted from the blood of 90 bat individuals (17 species) captured along Atlantic Forest fragments of Espírito Santo state, southeast Brazil. 18S ribosomal RNA was amplified by standard and/or nested PCR, then deep sequenced to recover and identify Operational Taxonomic Units (OTUs) for phylogenetic analysis. Blood samples from 34 bat individuals (13 species) tested positive for infection by 18S rRNA amplification. Amplicon sequences clustered to 14 OTUs, of which five were identified as Trypanosoma cruzi I, T. cruzi III/V, Trypanosoma cruzi marinkellei, Trypanosoma rangeli, and Trypanosoma dionisii, and seven were identified as novel genotypes monophyletic to basal T. cruzi clade types of the New World. Another OTU was identified as a trypanosome like those found in reptiles. Surprisingly, the remaining OTU was identified as Bodo saltans–closest non-parasitic relative of the trypanosomatid order. While three blood samples featured just one OTU (T. dionisii), all others resolved as mixed infections of up to eight OTUs. Conclusions/Significance: This study demonstrates the utility of next-generation barcoding methods to screen parasite diversity in mammalian reservoir hosts. We exposed high rates of local bat parasitism by multiple trypanosome species, some known to cause fatal human disease, others non-pathogenic, novel or yet little understood. Our results highlight bats as a long-standing nexus among host-parasite interactions of multiple niches, sustained in part by opportunistic and incidental infections of consequence to evolutionary theory as much as to public health. Author summary: Bats make up a mega-diverse, intensely parasitized order of volant mammals whose unique behavioural and physiological adaptations promote infection by a vast array of microorganisms. Trypanosomes stand out as ancient protozoan parasites of bats. As cryptic morphology, low parasitaemia and selective growth in culture have recurrently biased survey, we used 18S ribosomal RNA metabarcoding to resolve bat trypanosomatid diversity in Atlantic Forest fragments of southeast Brazil. Next to several unknown species, our deep sequence-based detection and assignment protocol recognized multiple known human-pathogenic trypanosomes, another linked to reptile hosts as well as a non-parasitic kinetoplastid in the blood of various phyllostomid bats. The striking permissivity exposed here, in a region where bat trypanosomes recently featured in a fatal case of Chagas disease, compels further research on bats’ role in the dispersal and spill-over of various microorganisms among humans and wildlife

Trypanosoma cruzi: adaptation to its vectors and its hosts

American trypanosomiasis is a parasitic zoonosis that occurs throughout Latin America. The etiological agent, Trypanosoma cruzi, is able to infect almost all tissues of its mammalian hosts and spreads in the environment in multifarious transmission cycles that may or not be connected. This biological plasticity, which is probably the result of the considerable heterogeneity of the taxon, exemplifies a successful adaptation of a parasite resulting in distinct outcomes of infection and a complex epidemiological pattern. In the 1990s, most endemic countries strengthened national control programs to interrupt the transmission of this parasite to humans. However, many obstacles remain to the effective control of the disease. Current knowledge of the different components involved in elaborate system that is American trypanosomiasis (the protozoan parasite T. cruzi, vectors Triatominae and the many reservoirs of infection), as well as the interactions existing within the system, is still incomplete. The Triatominae probably evolve from predatory reduvids in response to the availability of vertebrate food source. However, the basic mechanisms of adaptation of some of them to artificial ecotopes remain poorly understood. Nevertheless, these adaptations seem to be associated with a behavioral plasticity, a reduction in the genetic repertoire and increasing developmental instability

Conceptual approaches and methodological proposals for the study of interactions between environment and health: application to a research program on American trypanosomiasis

Las modificaciones del paisaje causadas por las actividades y migraciones humanas contribuyen en hacer emerger o re-emerger enfermedades tropicales, particularmente aquellas cuya transmisión se realiza por insectos vectores que a menudo deben escapar a las condiciones cambiantes ambientales, adaptándose y modificando sus redes tróficas, su morfología, hasta su genotipo. Obtener una mejor comprensión de las relaciones entre los factores ecológicos y humanos y las antropozoonosis es vital para poder identificar variables que permitan cartografiar el riesgo para las poblaciones humanas. Este es el objetivo del programa de investigación Ecología del Paisaje, Dinámica de los Agro-Ecosistemas y Complejos Eco-Patógenos: La Definición del Riesgo Eco-Epidemiológico en la Tripanosomiasis Americana que se desarrolla en diferentes ecosistemas del Brasil. Los autores describen las bases conceptuales y metodológicas del programa e insisten sobre el rol del método eco-epidemiológico para el estudio de la estructura y el funcionamiento de los focos naturales y antropizados de la infección. Modelizar su dinámica espacial y temporal permite concebir nuevos útiles de predicción y de vigilancia.Modifications of the landscape by human activity and migratory movements contribute to the emergence or reemergence of zoonotic and human diseases, particularly those transmitted by insects which often escape the changing environmental conditions, adapting and modifying their trophic networks and morphology, including their genotype. A better understanding of relationships between ecological factors, human factors, and anthropozoonoses is vital to be able to identify variables that allow one to map the risk for human populations. This is the main objective of the research program Landscape Ecology, Land-Use Dynamics, and Eco-Pathogenic Complexes: Eco-Epidemiologic Risk in the Case of American Trypanosomiasis, developed in various Brazilian ecosystems. The authors describe the program's conceptual and methodological basis and highlight the role of eco-epidemiology for studying the structure and function of natural and anthropogenic foci of infection. Modeling spatial and temporal dynamics can help predict and monitor such tropical diseases

High Trypanosoma spp. diversity is maintained by bats and triatomines in Espírito Santo state, Brazil

The aim of this study was to reevaluate the ecology of an area in the Atlantic Forest, southeast Brazil, where Chagas disease (CD) has been found to occur. In a previous study, immediately after the occurrence of a CD case, we did not observe any sylvatic small mammals or dogs with Trypanosoma cruzi cruzi infections, but Triatoma vitticeps presented high T. c. cruzi infection rates. In this study, we investigated bats together with non-volant mammals, dogs, and triatomines to explore other possible T. c. cruzi reservoirs/hosts in the area. Seventy-three non-volant mammals and 186 bats were captured at three sites within the Guarapari municipality, Espírito Santo state. Rio da Prata and Amarelos sites exhibited greater richness in terms of non-volant mammals and bats species, respectively. The marsupial Metachirus nudicaudatus, the rodent Trinomys paratus, and the bats Artibeus lituratus and Carollia perspicillata were the most frequently captured species. As determined by positive hemocultures, only two non-volant mammals were found to be infected by Trypanosoma species: Monodelphis americana, which was infected by T. cascavelli, T. dionisii and Trypanosoma sp., and Callithrix geoffroyi, which was infected by T. minasense. Bats presented T. c. cruzi TcI and TcIII/V, T. c. marinkellei, T. dionisii, T. rangeli B and D, and Trypanosoma sp. infections. Seven dogs were infected with T. cruzi based only on serological exams. The triatomines T. vitticeps and Panstrongylus geniculatus were found to be infected by trypanosomes via microscopy. According to molecular characterization, T. vitticeps specimens were infected with T. c. cruzi TcI, TcII, TcIII/V, and TcIV, T. c. marinkellei and T. dionisii. We observed high trypanosome diversity in a small and fragmented region of the Atlantic Forest. This diversity was primarily maintained by bats and T. vitticeps. Our findings show that the host specificity of the Trypanosoma genus should be thoroughly reviewed. In addition, our data show that CD cases can occur without an enzootic cycle near residential areas

Ecological scenario and Trypanosoma cruzi DTU characterization of a fatal acute Chagas disease case transmitted orally (Espírito Santo state, Brazil)

Submitted by Sandra Infurna ([email protected]) on 2016-12-09T13:37:11Z No. of bitstreams: 1 samanta_xavier_etal_IOC_2016.pdf: 1232916 bytes, checksum: cb48d61d779f9c21eabb66900de216bd (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2016-12-09T13:49:04Z (GMT) No. of bitstreams: 1 samanta_xavier_etal_IOC_2016.pdf: 1232916 bytes, checksum: cb48d61d779f9c21eabb66900de216bd (MD5)Made available in DSpace on 2016-12-09T13:49:04Z (GMT). No. of bitstreams: 1 samanta_xavier_etal_IOC_2016.pdf: 1232916 bytes, checksum: cb48d61d779f9c21eabb66900de216bd (MD5) Previous issue date: 2016Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia de Tripanossomatídeos. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia de Tripanossomatídeos. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia de Tripanossomatídeos. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia de Tripanossomatídeos. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia e Parasitologia de Mamíferos Silvestres Reservatórios. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia de Tripanossomatídeos. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia de Tripanossomatídeos. Rio de Janeiro, RJ, Brasil.Trypanosoma cruzi infection via oral route results in outbreaks or cases of acute Chagas disease (ACD) in different Brazilian regions and poses a novel epidemiological scenario. In the Espírito Santo state (southeastern Brazil), a fatal case of a patient with ACD led us to investigate the enzootic scenario to avoid the development of new cases. At the studied locality, Triatoma vitticeps exhibited high T. cruzi infection rates and frequently invaded residences

Leishmaniose visceral canina em Barra de Guaratiba, Rio de Janeiro, Brasil: avaliação dos fatores de risco

Barra de Guaratiba é uma região litorânea da cidade do Rio de Janeiro onde a leishmaniose visceral americana é endêmica. Apesar das medidas de controle aplicadas nessa localidade, incluindo sacrifício de cães e borrifação de inseticidas, a soroprevalência canina está estimada em 25% e durante 1995 e 1997, 8 casos humanos autóctones foram notificados. Para avaliar fatores de risco relacionados com o aumento da infecção por Leishmania (Leishmania) chagasi em cães, nós examinamos 365 cães utilizando a técnica de Imunofluorescência Indireta (IFAT) e capturamos flebótomos em ambientes doméstico e peridoméstico. Algumas variáveis relacionadas à infecção foram avaliadas por análise uni e multivariada. A distância da residência a borda da floresta, sua altitude e presença do gambá Didelphis marsupialis no quintal, foram considerados fatores preditores da infecção por Leishmania (Leishmania) chagasiem cães de Barra de Guaratiba. A presença de Lutzomyia longipalpis em ambiente peridoméstico indica a possibilidade de ocorrência de novos casos humanos. Nossos dados também sugerem a presença de um ciclo enzoótico nessa localidade.Barra de Guaratiba is a coastal area of the city of Rio de Janeiro where American visceral leishmaniasis (AVL) is endemic. Although control measures including killing of dogs and use of insecticides have been applied at this locality, the canine seroprevalence remains at 25% and during 1995 and 1997 eight autochthonous human cases were notified. In order to evaluate factors related to the increase of the risk for Leishmania (Leishmania) chagasi infection in dogs we have screened 365 dogs by anti-Leishmania immunofluorescent antibody test (IFAT) and captured sandflies in the domestic and peridomestic environment. Some variables related to the infection were assessed by uni- and multivariate analysis. The distance of the residence from the forest border, its altitude and the presence of the opossum Didelphis marsupialis in the backyard, were found predictor factors for L. (L.) chagasi infection in dogs in Barra de Guaratiba. The presence of Lutzomyia longipalpis in the peridomestic environment indicates the possibility of appearence of new human cases. Our data also suggest the presence of a sylvatic enzootic cycle at this locality

Témoignages d’enseignants européens

Pays-Bas Heleen Jansen  Quelques remarques préliminaires avant de commencer et de présenter ma vision personnelle des choses. Rappeler tout d’abord combien le métier d’enseignant est un beau métier. L’interaction avec les élèves reste toujours passionnante. Et même si la teneur de mon exposé peut parfois paraître un peu sombre, il n’en reste pas moins que stimuler les élèves dans leur développement demeure l’aspect le plus important de l’enseignement. Je voudrais relater la manière dont j’ai ..

Chagas Disease in Ancient Hunter-Gatherer Population, Brazil

Submitted by Sandra Infurna ([email protected]) on 2019-03-12T10:57:59Z No. of bitstreams: 1 anajansenanacvicente_etal_IOC_2008.pdf: 136856 bytes, checksum: 485cd5ad052e065339e3ce512de090b0 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-03-12T11:17:57Z (GMT) No. of bitstreams: 1 anajansenanacvicente_etal_IOC_2008.pdf: 136856 bytes, checksum: 485cd5ad052e065339e3ce512de090b0 (MD5)Made available in DSpace on 2019-03-12T11:17:57Z (GMT). No. of bitstreams: 1 anajansenanacvicente_etal_IOC_2008.pdf: 136856 bytes, checksum: 485cd5ad052e065339e3ce512de090b0 (MD5) Previous issue date: 2008Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Sem afiliaçãoFundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil

Modulating Variables ofTrypanosoma cruziandTrypanosoma evansiTransmission in Free-Ranging Coati (Nasua nasua) from the Brazilian Pantanal Region

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