chagas's disease in the amazon basin: 1. trypanosoma cruzi infections in silvatic mammals, triatomine bugs and man in the state of pará, north brazil.a total of 1,197 wild animals from pará state north brazil, were examined for haematozoa. trypanosoma cruzi-like parasites were found in 13 different species, and were particularly common in a variety of marsupials (didelphidae), porcupines (coendou spp.), armadillos (dasypus novemcinctus) and coatimundis(nasua nasua). three human infections are reported, making a total of seven autochthonous cases of chagas's disease from pará since the first were described in 1969. a serological survey of 5,31 ...1979112730
[the epidemiology of chagas' disease in a rural area of the city of teresina, piauí, brazil].in the rural areas of teresina, 129 triatomines were captured distributed in (a) artificial ecotopes; a house with one triatoma brasiliensis, one panstrongylus geniculatus, rhodnius pictipes, and one rhodnius prolixus and in a uninhabited chicken house (7 rhodnius nasutus). (b) natural ecotopes; pahus orbignya martiana (41 rhodnius neglectus, 33 rhodnius prolixus and 41 rhodnius nasutus) and copernicia cerifera (3 rhodnius neglectus). the 22.6% of captured triatomines were infected by flagellate ...19921308066
studies on vectors of trypanosoma cruzi in trinidad, west indies.studies on vectors of trypanosoma cruzi chagas were conducted during 1982-85 as part of an investigation on the epidemiological status of american trypanosomiasis in trinidad, west indies. a total of 148 reduviid bugs were collected from caves, armadillo nests and at light traps, comprising four sylvatic species and totalling 120 panstrongylus geniculatus (latreille), two p. rufotuberculatus (champion), twelve rhodnius pictipes stal and fourteen eratyrus mucronatus stal. a significantly higher l ...19921421480
chagas disease in ecuador: a sylvatic focus in the amazon region.a sylvatic focus of chagas disease is reported in the amazon region of ecuador (provinces of napo and sucumbios). during 1987-1989, 10 cases of acute infection were diagnosed by direct visualization of trypanosoma cruzi in peripheral blood smears during routine malaria checks. also in that region, three triatomine bugs, rhodnius pictipes, rhodnius robustus and panstrongylus geniculatus were found naturally infected with t. cruzi suggesting that the human cases represent an autochthonous focus of ...19911904944
[natural hosts of trypanosoma cruzi in french guiana. high endemicity of zymodeme 1 in wild marsupials].during an epidemiological survey in french guiana, three species of marsupiala were found infected by trypanosoma cruzi with high infection rates (30,8% for didelphis marsupialis). six triatomine bug species were recorded, five of them being well known vectors of chagas' disease. iso-enzyme characterization of 22 stocks isolated (16 from d. marsupialis, 3 from philander opossum and 3 from rhodnius prolixus) revealed that they were all related to zymodeme 1 of miles. the silvatic cycle is endemic ...19853923891
vertebrate hosts and vectors of trypanosoma rangeli in the amazon basin of brazil.a total of 46 trypanosoma rangeli stocks were isolated from naturally infected mammals and triatomine vectors. twenty-two stocks were from the common opossum (didelphis marsupialis), one from the brown "4-eyed" opossum (metachirus nudicaudatus), one from the anteater (tamandua tetradactyla), one from the coati (nasua nasua), seven from rhodnius pictipes and 14 from rhodnius robustus. two stocks were also isolated from recently fed sandflies (lutzomyia sp., shannoni group). the stocks were identi ...19836418015
chagas' disease in the amazon basin: v. periurban palms as habitats of rhodnius robustus and rhodnius pictipes--triatomine vectors of chagas' disease.trypanosoma cruzi infected rhodnius robustus and/or rhodnius pictipes were commonly found, in large numbers, in the brazilian amazonian palms maximiliana regia ("inajá"), acrocomia sclerocarpa ("mucajá") and orbignya speciosa ("babaçu"). the common opossum, didelphis marsupialis, was the animal most frequently associated with triatomine infested palms. r. pictipes, frequently light-attracted into houses from palm trees, was the probable source of an acute case of chagas' disease in the vicinity ...19836443629
field application of polymerase chain reaction diagnosis and strain typing of trypanosoma cruzi in bolivian triatomines.a new approach for direct identification and characterization of trypanosoma cruzi stocks in biological samples was tested for field applicability on an extensive sample of feces collected from triatomine vectors from four different species found in bolivia. the first step of the technique is polymerase chain reaction (pcr) amplification of the hypervariable region of kinetoplast dna minicircles of t. cruzi parasites. in this report, 345 fecal samples were analyzed and the pcr results were compa ...19957677221
[biology of rhodnius pictipes stal, 1872 under laboratory conditions (hemiptera, reduviidae, triatominae)].rhodnius pictipes stal, 1872 is a silvatic species with a widespread distribution in south america, found in nine brazilian states, naturally infected by trypanosoma cruzi and t. rangeli. the individual rearing of this species under laboratory conditions, allowed the following biological aspects to be observed: incubation time, search for first meal after eclosion or moult, time-lapse between presentation of the blood meal and the beginning of feeding, duration of blood meal, time and place of d ...19947885255
[trypanosoma cruzi in french guinea: review of accumulated data since 1940].between 1939 and 1994, nine cases of chagas disease have been reported in french guiana: seven in the acute phase including two that were fatal and two in the chronic phase with cardiac sequellae. a tenth case of transient parasitemia was described but the patient's clinical status was not mentioned. screening by xenodiagnosis revealed one subclinical infection. heart disease is a highly specific manifestation of trypanosoma cruzi infection, this being consistent with the known presence of zymod ...19968767800
[acute chagas cardiopathy. a systematic study of the intracardiac excitatory-conduction and autonomic nervous systems in an autochthonous case in acre].the histopathology of the heart is described in an acute case of chagas' disease (dc). lesions involving the conducting system (sc) and the autonomic intracardiac nervous system (snaic) are emphasized. light microscopy showed acute pan-carditis with plenty of trypanosoma cruzi amastigotes within heart muscle cells. multiple inflammatory foci were found in the sc with parasitic nests within the atrioventricular node and left his bundle. there were also severe atrial periganglionitis and perineuri ...19968768587
random amplification of polymorphic dna as a tool for taxonomic studies of triatomine bugs (hemiptera: reduviidae).eleven of 27 decameric primers were found to be suitable for random amplification of polymorphic dna (rapd) from triatomine bugs on the basis that they produced discrete profiles and distinguished among panstrongylus megistus (burmeister), rhodnius prolixus stål, and triatoma infestans (klug). the legs, or single leg segments, of individual bugs were used as the source of dna so that the taxonomic value of the bug was conserved. within the scope of the specimens studied, rapd profiles allowed as ...19989542343
selection of trypanosoma cruzi clonal genotypes (clonet 20 and 39) isolated from bolivian triatomines following subculture in liquid medium.previous studies showed that two groups of trypanosoma cruzi clonal genotypes named clonet 20 and clonet 39 were predominant in triatoma infestans, the unique vector of chagas disease in bolivia. these groups of clones correspond to distinct genetic clusters. these clonets were detected in t. infestans and rhodnius pictipes fecal samples before isolation and after culture by kdna pcr (polymerase chain reaction) and hybridization of the amplified products with clonet specific kdna probes named 20 ...200010998206
phylogeny and molecular taxonomy of the rhodniini derived from mitochondrial and nuclear dna sequences.eleven species of rhodnius and one of psammolestes were compared by dna sequence analysis of fragments of the mitochondrial large subunit ribosomal rna (mtlsurrna), the mitochondrial cytochrome b (mtcytb), and the d2 variable region of the 28s nuclear rna (d2), totaling 1,429 base pairs. the inferred phylogeny, using triatoma infestans as an outgroup, revealed two main clades within the rhodniini--one, including the prolixus group of species (rhodnius prolixus, rhodnius robustus, rhodnius neglec ...200011220761
emerging chagas disease: trophic network and cycle of transmission of trypanosoma cruzi from palm trees in the amazon.a trophic network involving molds, invertebrates, and vertebrates, ancestrally adapted to the palm tree (attalaea phalerata) microhabitat, maintains enzootic trypanosoma cruzi infections in the amazonian county paço do lumiar, state of maranhão, brazil. we assessed seropositivity for t. cruzi infections in the human population of the county, searched in palm trees for the triatomines that harbor these infections, and gathered demographic, environmental, and socioeconomic data. rhodnius pictipes ...200111266300
on the possibility of autochthonous chagas disease in roraima, amazon region, brazil, 2000-2001.chagas disease has been almost entirely eradicated from the arid zones in central and northeastern brazil where rare or no autochthonous cases have been reported. however, in the last 10 years the disease has increasingly been registered in the amazon region. aiming to investigate the possibility of the occurrence of autochthonous cycle of chagas disease in roraima, triatomine collections, vectorial susceptibility studies (this one to be shown elsewhere), parasitological and serological analyses ...200515729474
[seroepidemiology of chagas disease in two rural populations in the municipality of costa de oro, at aragua state, northern venezuela].chagas disease has been a public health problem in latin america for many years. in venezuela the disease is mainly distributed in the rural populations and endemic areas with an overall seroprevalence index of 8,3% for the year 2000.200818645666
analysis of an acute chagas disease outbreak in the brazilian amazon: human cases, triatomines, reservoir mammals and outbreak of chagas disease occurred in mazagão, amapá, brazilian amazon in 1996. seventeen of 26 inhabitants presented symptoms compatible with acute chagas disease and were submitted to parasitological and serological tests. all 17 were positive in at least one parasitological test and 11 were also igm or igg anti-trypanosoma cruzi positive. the nine asymptomatic patients were negative for parasites and one was positive for igg anti-t. cruzi. sixty-eight triatomines were captured (66 rhodniu ...200919118852
reassessing the entomological investigation around the first autochthonous case of chagas disease in western brazilian 1979, the first autochthonous case of chagas disease in the western brazilian amazon was reported and an entomological survey was carried out around it. specimens of rhodnius pictipes and rhodnius robustus were collected in intradomicile and sylvatic ecotopes. adult bugs were infected with trypanosomatids. invasion of houses by triatomines was demonstrated and the presence of infected bugs inside dwellings was associated with the possibility of vector-borne chagas disease. continuous entomolo ...200919274387
[occurrences of triatomines in wild and domestic environments in the municipality of manaus, state of amazonas].analysis of the distribution of triatomines is essential for formulating control strategies for chagas disease in the amazon region. in this paper, the results from trapping in wild and artificial environments in rural and urban localities in manaus, amazonas, are presented. out of the 115 triatomines collected, 85 (73.9%) were of the species rhodnius pictipes, 25 (21.7%) of rhodnius robustus and five (4.4%) of panstrongylus geniculatus. the rate of natural infection by flagellates was 5.9% for ...200920209347
epidemiological investigation of an acute case of chagas disease in an area of active transmission in peruvian amazon region.the study objective was to investigate an acute case of chagas disease in the san pedro de shishita community, pebas district, in the peruvian amazon basin, a non-endemic area. both parents of the index case (acute case) were thoroughly interviewed, a seroepidemiological survey was carried out in the community, parasitological exams were carried out only in relatives of the index case, and triatomine bugs were searched for inside houses, peridomiciliary, and in wild environments. seroprevalence ...201021049232
attraction of chagas disease vectors (triatominae) to artificial light sources in the canopy of primary amazon triatomines occasionally fly into artificially lit premises in amazonia. this can result in trypanosoma cruzi transmission to humans either by direct contact or via foodstuff contamination, but the frequency of such behaviour has not been quantified. to address this issue, a light-trap was set 45 m above ground in primary rainforest near manaus, state of amazonas, brazil and operated monthly for three consecutive nights over the course of one year (432 trap-hours). the most commonly caught ...201021225207
amazonian triatomine biodiversity and the transmission of chagas disease in french guiana: in medio stat sanitas.the effects of biodiversity on the transmission of infectious diseases now stand as a cornerstone of many public health policies. the upper amazonia and guyana shield are hot-spots of biodiversity that offer genuine opportunities to explore the relationship between the risk of transmission of chagas disease and the diversity of its triatomine vectors. over 730 triatomines were light-trapped in four geomorphological landscapes shaping french-guiana, and we determined their taxonomic status and in ...201626867025
triatominae species of suriname (heteroptera: reduviidae) and their role as vectors of chagas disease.nine species of triatominae, representing three tribes and five genera, are currently known in suriname. an annotated list of the species based on the collections of the bureau of public health (suriname), the national zoological collection suriname and the national history museum leiden (the netherlands) is provided. additionally, the results of several years of opportunistic collection in two domestic environments are presented. the most common species are rhodnius pictipes stål, 1972, rhodniu ...201425004146
geographic distribution of chagas disease vectors in brazil based on ecological niche modeling.although brazil was declared free from chagas disease transmission by the domestic vector triatoma infestans, human acute cases are still being registered based on transmission by native triatomine species. for a better understanding of transmission risk, the geographic distribution of brazilian triatomines was analyzed. sixteen out of 62 brazilian species that both occur in >20 municipalities and present synanthropic tendencies were modeled based on their ecological niches. panstrongylus genicu ...201222523500
molecular identification of wild triatomines of the genus rhodnius in the bolivian amazon: strategy and current difficulties.the amazon region has recently been considered as endemic in latin america. in bolivia, the vast amazon region is undergoing considerable human migrations and substantial anthropization of the environment, potentially renewing the danger of establishing the transmission of chagas disease. the cases of human oral contamination occurring in 2010 in the town of guayaramerín provided reasons to intensify research. as a result, the goal of this study was to characterize the species of sylvatic triato ...201728274885
correlation between populations of rhodnius and presence of palm trees as risk factors for the emergence of chagas disease in amazon region, brazil.among the states that comprise the legally defined amazon region of brazil, pará has presented the highest occurrences of acute cases of chagas disease over the last two decades. these cases have been attributed to consumption of fruits from native palm trees. in surveys in rural and wild areas of the municipality of oriximiná, pará, triatomine fauna, their main ecotopes and the infection rate due to trypanosoma cruzi were identified using active and passive search methods: manual capture and no ...201222664419
ecology of rhodnius robustus larrousse, 1927 (hemiptera, reduviidae, triatominae) in attalea palm trees of the tapajós river region (pará state, brazilian amazon).the rising number of acute cases of chagas disease in the state of pará, reported in the past two decades, has been associated, in part, with the ingestion of juice of local palm tree fruits, mainly açaí berry and bacaba. near the study area, in santarém, pará state, an outbreak of chagas disease has been notified and investigations suggest the consumption of bacaba juice as the main source of infection with t. cruzi. the purpose of this study is to assess the aspects associated to the ecology o ...201424690302
new focus of active transmission of chagas disease in indigenous populations in the peruvian amazon basin.several cases of acute chagas disease (acd) have been reported in the peruvian amazon basin.201323856870
Displaying items 1 - 29 of 29