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1.
Rev Soc Bras Med Trop ; 54: e0873-2020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33759934

RESUMO

Chagas disease is caused by the protozoan Trypanosoma cruzi. Seven lineages have been identified based on different molecular markers, namely TcI, TcII, TcIII, TcIV, TcV, TcVI, and TcBat. Dogs play the role of epidemiological sentinels being domestic reservoirs of T. cruzi. The aim of the current study was to report the first case of CD in a domestic dog in Manaus, Amazonas, Brazil, infected with T. cruzi DTU TcIV. We hope our report encourages veterinarians and surveillance professionals to a take a deeper look at T. cruzi infection in domestic animals.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Animais , Brasil , Doença de Chagas/diagnóstico , Doença de Chagas/veterinária , Cães , Genótipo , Trypanosoma cruzi/genética
2.
Rev Soc Bras Med Trop ; 54: e04712020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33656149

RESUMO

INTRODUCTION: This communication reports the colonization of Panstrongylus megistus in an urban area of the municipality of Taboão da Serra in the metropolitan region of São Paulo. METHODS: After receiving a notification from the population, entomological research comprising active search, collection, identification, and examination of triatomines was conducted. Wild animals were captured and examined. RESULTS: A colony of triatomines was found to be associated with dogs in the backyard of the property. CONCLUSIONS: The colonization of P. megistus shows the potential for their occupation of artificial ecotopes, which may pose a risk to the human population.


Assuntos
Doença de Chagas , Didelphis , Panstrongylus , Triatominae , Animais , Brasil , Doença de Chagas/veterinária , Cidades , Cães , Insetos Vetores
3.
PLoS Negl Trop Dis ; 14(12): e0008932, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33332357

RESUMO

BACKGROUND: Chagas disease is a neglected zoonosis of growing concern in the southern US, caused by the parasite Trypanosoma cruzi. We genotyped parasites in a large cohort of PCR positive dogs to shed light on parasite transmission cycles and assess potential relationships between parasite diversity and serological test performance. METHODOLOGY/PRINCIPAL FINDINGS: We used a metabarcoding approach based on deep sequencing of T. cruzi mini-exon marker to assess parasite diversity. Phylogenetic analysis of 178 sequences from 40 dogs confirmed the presence of T. cruzi discrete typing unit (DTU) TcI and TcIV, as well as TcII, TcV and TcVI for the first time in US dogs. Infections with multiple DTUs occurred in 38% of the dogs. These data indicate a greater genetic diversity of T. cruzi than previously detected in the US. Comparison of T. cruzi sequence diversity indicated that highly similar T. cruzi strains from these DTUs circulate in hosts and vectors in Louisiana, indicating that they are involved in a shared T. cruzi parasite transmission cycle. However, TcIV and TcV were sampled more frequently in vectors, while TcII and TcVI were sampled more frequently in dogs. CONCLUSIONS/SIGNIFICANCE: These observations point to ecological host-fitting being a dominant mechanism involved in the diversification of T. cruzi-host associations. Dogs with negative, discordant or confirmed positive T. cruzi serology harbored TcI parasites with different mini-exon sequences, which strongly supports the hypothesis that parasite genetic diversity is a key factor affecting serological test performance. Thus, the identification of conserved parasite antigens should be a high priority for the improvement of current serological tests.


Assuntos
Doença de Chagas/veterinária , Éxons/genética , Variação Genética , Trypanosoma cruzi/genética , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Estudos de Coortes , Cães , Genótipo , Humanos , Louisiana/epidemiologia , Filogenia , Testes Sorológicos/veterinária , Trypanosoma cruzi/imunologia , Trypanosoma cruzi/fisiologia , Zoonoses
4.
Exp Parasitol ; 215: 107931, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464222

RESUMO

Chagas disease is a public health problem in America. Its parasite, Trypanosoma cruzi, presents different discrete typing units (DTUs), colonizes organs of mammalian hosts in chronic infections, and presents tropism for particular organs in experimental infections. We evaluated T. cruzi tropism towards organs on the naturally infected rodent Octodon degus, identifying the parasites' DTUs, by means of conventional PCR and hybridization. Almost all the analyzed organs presented T. cruzi. More than 42% of the tested oesophagus, skin, skeletal muscle, brain and intestine showed T. cruzi DNA. Other nine types of organs were infected in over 15%. These results suggest that there is some tropism by T. cruzi in chronically infected O. degus. DTU TcV was present in 92.5% of infected organs with identified DTUs; this DTU is frequently reported in human infections in the Southern Cone of South America. Few organs showed mixed DTU infections. This is one of the few reports on the outcome of chronic natural T. cruzi-infection in wild mammal hosts exposed to naturally infected vectors.


Assuntos
Doença de Chagas/veterinária , Octodon/parasitologia , Doenças dos Roedores/patologia , Doenças dos Roedores/parasitologia , Animais , Animais Selvagens , Doença de Chagas/parasitologia , Doença de Chagas/patologia , DNA de Protozoário/isolamento & purificação , Feminino , Masculino , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética
5.
Am J Trop Med Hyg ; 103(1): 428-436, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32458775

RESUMO

Trypanosoma cruzi is the etiological agent of Chagas disease that infects more than seven million people in Latin America. The parasite is transmitted by triatomine insects, of which some species are often associated with palms. The establishment of oil palm plantations (Elaeis guineensis) in the Orinoco region (Colombia) has been rapidly growing, possibly constituting a new environment for the establishment and increase in triatomine populations. In this study, the potential of Rhodnius prolixus to colonize E. guineensis plantations and maintain T. cruzi transmission was assessed. Fieldwork was conducted in two areas located in the department of Casanare for sampling E. guineensis and Attalea butyracea palms, sampling for triatomines to determine their abundance and prevalence of T. cruzi infection. To assess T. cruzi transmission potential in the area, sylvatic and domestic mammals were sampled. Results showed that palm infestation with triatomines was higher in A. butyracea than in E. guineensis palms and T. cruzi infection in triatomines varied between habitats for one study area, but was constant in the other site. Trypanosoma cruzi-infected mammals in the E. guineensis plantations were mainly generalist rodents, suggesting that these mammals could have an important role in T. cruzi transmission in plantations. In conclusion, E. guineensis plantations in the Orinoco region are suitable habitats for R. prolixus and T. cruzi transmission.


Assuntos
Arecaceae , Doença de Chagas/veterinária , Insetos Vetores/parasitologia , Rhodnius/parasitologia , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Quirópteros/parasitologia , Colômbia/epidemiologia , Cães/parasitologia , Florestas , Gambás/parasitologia , Óleo de Palmeira , Roedores/parasitologia , Sus scrofa/parasitologia , Trypanosoma cruzi
6.
BMC Vet Res ; 16(1): 101, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228593

RESUMO

BACKGROUND: Chagas disease is increasingly recognized in the southern U.S., where triatomine vectors transmit Trypanosoma cruzi among wildlife and domestic dogs with occasional vector spillover to humans. As in humans, clinical outcome in dogs is variable, ranging from acute death to asymptomatic infections or chronic heart disease. In order to characterize cardiac manifestations of T. cruzi infections, we tracked a cohort of naturally-infected dogs and a matched cohort of uninfected dogs. We hypothesized that selected measures of cardiac disease (abnormal rate, abnormal rhythm, and elevated cardiac troponin I (cTnI; a biomarker of cardiac injury)) would occur more commonly in infected than uninfected dogs matched by age, breed, sex and location. In addition to the clearly positive and negative dogs, we specifically tracked dogs with discordant test results across three independent serological assays to gather clinical data that might elucidate the infection status of these animals and inform the utility of the different testing approaches. RESULTS: We placed an ambulatory ECG monitor (Holter) on 48 government working dogs and analyzed 39 successful recordings that met length and quality criteria from 17 T. cruzi-infected, 18 uninfected dogs and 4 dogs with discordant results. Overall, 76.5% of positive, 100.0% of discordant, and 11.1% of negative dogs showed > 1 ECG abnormality (p < 0.0001), and positive and discordant dogs had a higher mean number of different types of ECG abnormalities than negative dogs (p < 0.001-0.014). The most common cardiac abnormalities included supraventricular and ventricular arrhythmias and atrioventricular block. Positive dogs had higher serum concentrations of cTnI than both negative dogs (p = 0.044) and discordant dogs (p = 0.06). Based on dog handler reports, nearly all (4/5; 80%) dogs with reported performance decline or fatigue were T. cruzi-infected dogs. CONCLUSIONS: Further understanding cardiac manifestations in dogs naturally infected with T. cruzi is critical for prognostication, establishing a baseline for drug and vaccine studies, and better understanding of zoonotic risk.


Assuntos
Doença de Chagas/veterinária , Doenças do Cão/parasitologia , Cardiopatias/veterinária , Animais , Arritmias Cardíacas/complicações , Arritmias Cardíacas/veterinária , Doença de Chagas/complicações , Doença de Chagas/epidemiologia , Doenças do Cão/epidemiologia , Cães , Eletrocardiografia Ambulatorial/veterinária , Feminino , Masculino , Testes Sorológicos/veterinária , Texas/epidemiologia , Troponina I/sangue , Trypanosoma cruzi/isolamento & purificação
7.
Am J Trop Med Hyg ; 102(5): 1078-1085, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32189615

RESUMO

Trypanosoma cruzi is a zoonotic protozoan parasite vectored by triatomine insects that are endemic to the Americas, including the southern United States. Surveillance of domestic dogs for T. cruzi exposure allows for the determination of geographic regions of transmission that are relevant for human and animal health. The U.S. Department of Homeland Security (DHS) working dogs provide critical security and detection services across the country, and many train or work in the southern United States, where they are at risk for T. cruzi exposure. We sampled blood from 1,610 working dogs (predominantly Belgian Malinois, German shepherds, and Labrador retrievers) from six task forces (including the Transportation Security Administration, Customs and Border Protection, Secret Service, and more) and two canine training centers across 41 states from 2015 to 2018. Canine sera that were reactive on at least two independent serological assays were considered positive for anti-T.-cruzi antibodies. In addition, up to three independent polymerase chain reaction (PCR) assays were used to detect and type T. cruzi DNA. Overall seroprevalence was 7.5%, and four dogs (0.25%, n = 1,610) had detectable parasite DNA in the blood, comprising parasite discrete taxonomic units (DTUs) TcIV and a coinfection of TcI/TcIV. Dogs that worked within versus outside of the geographic range of established triatomines showed comparable seroprevalence (7.3% and 9.2%, respectively; P = 0.61). Determining the prevalence of T. cruzi in these working dogs and looking at spatially associated risk factors have practical implications for disease risk management and could assist with improved control measures to protect both animal and human health.


Assuntos
Doença de Chagas/veterinária , Doenças do Cão/parasitologia , Trypanosoma cruzi , Animais , Doença de Chagas/epidemiologia , Estudos Transversais , Doenças do Cão/epidemiologia , Cães/psicologia , Humanos , Aplicação da Lei , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia
8.
Parasitol Int ; 76: 102065, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32001348

RESUMO

Trypanosoma cruzi, the causative agent of Chagas disease, and Toxoplasma gondii, which is responsible for Toxoplasmosis, are two parasites that cause significant protozoan zoonoses and consequently important economic losses in human, companion animals and livestock. For the congenital transmission to occur, both parasites must cross the barrier present in the mammalian placenta, which differs between species. Particularly, hemochorial, endotheliochorial and epitheliochorial placental barriers are present, respectively, in human, dog and sheep. The type of placental barrier has been associated with the probability of transmission of pathogens. In this study, we used experimental placental ex vivo infection models of T. cruzi and T. gondii in the above-mentioned mammals in order to study tissue alterations and to compare infection efficiency. Here, we infected placental term explants from human, dog and sheep and analyzed tissue damage by standard histological and histochemical methods. Comparative infection efficiency was determined by quantitative PCR. Both parasites are able to infect the different placental explants; however, more T. gondii parasites were detected, and T. gondii causes a more severe tissue damage in human and canine explants than T. cruzi. The histopathological changes observed in ovine placenta explants were similar in presence of both parasites. We conclude that the infection efficiency of T. gondii is higher, compared to T. cruzi, during the ex vivo infection of human, canine and ovine placental explants. In addition, the ex vivo infection of mammalian placental explants constitutes an interesting experimental approach to study part of the infection mechanisms as well as host responses during congenital infection of both parasites.


Assuntos
Doença de Chagas/patologia , Placenta/patologia , Placenta/parasitologia , Toxoplasmose Animal/patologia , Toxoplasmose/patologia , Animais , Doença de Chagas/veterinária , Cães/parasitologia , Feminino , Humanos , Técnicas In Vitro , Gravidez , Ovinos/parasitologia , Toxoplasma/patogenicidade , Trypanosoma cruzi/patogenicidade
9.
Vet Parasitol ; 278: 109014, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31972512

RESUMO

Trypanosoma cruzi is a zoonotic protozoan parasite transmitted by triatomines that infects a wide range of mammals. South Texas is a hotspot for triatomines, T. cruzi-infected dogs and wildlife, and local transmission to humans also occurs. However, little is known about the infection of domestic cats (Felis catus) in the United States. Given the role cats play in the ecology of T. cruzi in Mexico and South America, we hypothesized that T. cruzi infection occurs in cats from south Texas, sometimes associated with cardiac pathology. In 2017, 167 euthanized cats from a south Texas shelter were sampled across winter, spring, and summer. We collected whole blood and hearts from all cats, with additional tissues from a subset. Serum samples were screened for T. cruzi antibodies using two independent rapid immunochromatographic tests and an indirect fluorescent antibody test. Cats were considered seropositive if they were positive on at least two independent serological tests. Blood clot, heart tissue and other tissues were subjected to qPCR for parasite detection and discrete typing unit (DTU) determination. Tissues from selected seropositive or PCR-positive animals and a subset of negative animals were processed routinely for histopathology and examined by a board-certified pathologist. A total of 19 cats (11.4%) were seropositive and three cats (1.8%) - one of which was seropositive - had one or more PCR-positive tissues. Infected tissues included heart, bicep femoris muscle, sciatic nerve, esophagus, and mesentery. Genotyping of the parastite to the level of DTU showed that exclusively DTU TcI was present, despite past studies showing both TcI and TcIV in vectors of the region. Eight of 19 (42.1%) seropositive cats exhibited lymphoplasmacytic inflammation, sometimes with fibrosis, in cardiac tissue compared to 28.6% of 28 seronegative cats (P = 0.10). Domestic cats are affected hosts in the eco-epidemiology of Chagas disease. Future prospective studies are needed to understand disease progression. Veterinarians in the southern United States should consider T. cruzi in their index of suspicion in cats with exposure to vectors and undetermined cardiac abnormalities.


Assuntos
Doenças do Gato/epidemiologia , Doença de Chagas/veterinária , Miocárdio/patologia , Animais , Doenças do Gato/parasitologia , Gatos , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Coração/parasitologia , Imunoensaio/veterinária , Masculino , Prevalência , Texas/epidemiologia
10.
PLoS One ; 15(1): e0227828, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951634

RESUMO

Trypanosoma cruzi, the protozoan agent of Chagas disease in the Americas, is comprised of six genetic lineages (TcI-TcVI) and a possible seventh (TcBat, related to TcI). Identification of T. cruzi lineages infecting reservoir mammalian species is fundamental to resolving transmission cycles. However, this is hindered by the limited sensitivity and technical complexity of parasite isolation and genotyping. An alternative approach is serology using T. cruzi lineage-specific epitopes, such as those of the trypomastigote small surface antigen (TSSA). For surveillance of T. cruzi lineage infections in mammal species from diverse Brazilian regions, we apply a novel rapid diagnostic test (RDT, Chagas Sero K-SeT), which incorporates the TSSA peptide epitope specific to TcII/V/VI (TSSApep-II/V/VI) and Protein G detection of antibodies. Chagas Sero K-SeT RDT results with sera from experimentally infected mice, from tamarin primates (Leontopithecus spp.) and from canines (Canis familiaris) were concordant with corresponding TSSApep-II/V/VI ELISAs. The Chagas Sero K-Set detected TcII/V/VI infections in Leontopithecus spp. from the Atlantic forest (n = 46), in C. familiaris (n = 16) and Thrichomys laurentius (n = 2) from Caatinga biome and Chiroptera (n = 1) from Acre, Amazonia. The Chagas Sero K-SeT RDT is directly applicable to TcII/V/VI-specific serological surveillance of T. cruzi infection in several different mammalian Orders. It can replace ELISAs and provides efficient, point-of-sampling, low-cost detection of TcII/V/VI infections, with at least equivalent sensitivity, although some mammals may be difficult to trap, and, not unexpectedly, Chagas Sero K-SeT could not recognise feline IgG. Knowledge of sylvatic hosts of T. cruzi can be expanded, new reservoir species discovered, and the ecology of transmission cycles clarified, particularly with adaptation to further mammalian Orders.


Assuntos
Doença de Chagas/veterinária , Trypanosoma cruzi/isolamento & purificação , Animais , Antígenos de Protozoários/sangue , Antígenos de Protozoários/imunologia , Brasil/epidemiologia , Gatos , Doença de Chagas/sangue , Doença de Chagas/diagnóstico , Testes Diagnósticos de Rotina , Cães , Ensaio de Imunoadsorção Enzimática , Humanos , Camundongos , Trypanosoma cruzi/imunologia
11.
Parasit Vectors ; 12(1): 567, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783770

RESUMO

BACKGROUND: A question of epidemiological relevance in Chagas disease studies is to understand Trypanosoma cruzi transmission cycles and trace the origins of (re)emerging cases in areas under vector or disease surveillance. Conventional parasitological methods lack sensitivity whereas molecular approaches can fill in this gap, provided that an adequate sample can be collected and processed and a nucleic acid amplification method can be developed and standardized. We developed a duplex qPCR assay for accurate detection and quantification of T. cruzi satellite DNA (satDNA) sequence in samples from domestic and sylvatic mammalian reservoirs. The method incorporates amplification of the gene encoding for the interphotoreceptor retinoid-binding protein (IRBP), highly conserved among mammalian species, as endogenous internal amplification control (eIAC), allowing distinction of false negative PCR findings due to inadequate sample conditions, DNA degradation and/or PCR interfering substances. RESULTS: The novel TaqMan probe and corresponding primers employed in this study improved the analytical sensitivity of the assay to 0.01 par.eq/ml, greater than that attained by previous assays for Tc I and Tc IV strains. The assay was tested in 152 specimens, 35 from 15 different wild reservoir species and 117 from 7 domestic reservoir species, captured in endemic regions of Argentina, Colombia and Mexico and thus potentially infected with different parasite discrete typing units. The eIACs amplified in all samples from domestic reservoirs from Argentina and Mexico, such as Canis familiaris, Felis catus, Sus scrofa, Ovis aries, Equus caballus, Bos taurus and Capra hircus with quantification cycles (Cq's) between 23 and 25. Additionally, the eIACs amplified from samples obtained from wild mammals, such as small rodents Akodon toba, Galea leucoblephara, Rattus rattus, the opossums Didelphis virginiana, D. marsupialis and Marmosa murina, the bats Tadarida brasiliensis, Promops nasutus and Desmodus rotundus, as well as in Conepatus chinga, Lagostomus maximus, Leopardus geoffroyi, Lepus europaeus, Mazama gouazoubira and Lycalopex gymnocercus, rendering Cq's between 24 and 33. CONCLUSIONS: This duplex qPCR assay provides an accurate laboratory tool for screening and quantification of T. cruzi infection in a vast repertoire of domestic and wild mammalian reservoir species, contributing to improve molecular epidemiology studies of T. cruzi transmission cycles.


Assuntos
Doença de Chagas/veterinária , Reservatórios de Doenças/parasitologia , Mamíferos/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Doença de Chagas/diagnóstico , Primers do DNA/genética , Sondas de DNA/genética , DNA de Protozoário/isolamento & purificação , DNA Satélite/isolamento & purificação , Proteínas do Olho/genética , Proteínas de Ligação ao Retinol/genética , Sensibilidade e Especificidade , Trypanosoma cruzi
12.
PLoS Negl Trop Dis ; 13(12): e0007902, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31834879

RESUMO

Trypanosoma cruzi is the causative agent of Chagas disease, a Neglected Tropical Disease affecting 8 million people in the Americas. Triatomine hematophagous vectors feed on a high diversity of vertebrate species that can be reservoirs or dead-end hosts, such as avian species refractory to T. cruzi. To understand its transmission dynamics in synanthropic and domesticated species living within villages is essential to quantify disease risk and assess the potential of zooprophylaxis. We developed a SI model of T. cruzi transmission in a multi-host community where vector reproduction and parasite transmission depend on a triatomine blood-feeding rate accounting for vector host preferences and interference while feeding. The model was parameterized to describe T. cruzi transmission in villages of the Yucatan peninsula, Mexico, using the information about Triatoma dimidiata vectors and host populations accumulated over the past 15 years. Extensive analyses of the model showed that dogs are key reservoirs and contributors to human infection, as compared to synanthropic rodents and cats, while chickens or other domesticated avian hosts dilute T. cruzi transmission despite increasing vector abundance. In this context, reducing the number of dogs or increasing avian hosts abundance decreases incidence in humans by up to 56% and 39%, respectively, while combining such changes reduces incidence by 71%. Although such effects are only reached over >10-years periods, they represent important considerations to be included in the design of cost-effective Integrated Vector Management. The concomitant reduction in T. cruzi vector prevalence estimated by simulating these zooprophylactic interventions could indeed complement the removal of colonies from the peridomiciles or the use of insect screens that lower vector indoor abundance by ~60% and ~80%. These new findings reinforce the idea that education and community empowerment to reduce basic risk factors is a cornerstone to reach and sustain the key objective of interrupting Chagas disease intra-domiciliary transmission.


Assuntos
Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Doença de Chagas/transmissão , Reservatórios de Doenças/parasitologia , Transmissão de Doença Infecciosa , Insetos Vetores/crescimento & desenvolvimento , Triatoma/crescimento & desenvolvimento , Animais , Doença de Chagas/veterinária , Simulação por Computador , Humanos , Incidência , México
13.
Ecohealth ; 16(3): 523-533, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31583491

RESUMO

Rattus spp. are reservoirs of many human zoonoses, but their role in domestic transmission cycles of human trypanosomiasis is underestimated. In this study, we report trypanosome-infected Rattus norvegicus and Rattus rattus in human dwellings in slums neighboring Maracay, a large city near Caracas, the capital of Venezuela. Blood samples of R. norvegicus and R. rattus examined by PCR and FFLB (fluorescent fragment length barcoding) revealed a prevalence of 6.3% / 31.1% for Trypanosoma lewisi (agent of rat- and flea-borne human emergent zoonosis), and 10.5% / 24.6% for Trypanosoma cruzi (agent of Chagas disease). Detection in flea guts of T. lewisi (76%) and, unexpectedly, T. cruzi (21.3%) highlighted the role of fleas as carriers and vectors of these trypanosomes. A high prevalence of rats infected with T. lewisi and T. cruzi and respective flea and triatomine vectors poses a serious risk of human trypanosomiasis in Venezuelan slums. Anthropogenic activities responsible for growing rat and triatomine populations within human dwellings drastically increased human exposure to trypanosomes. This scenario has allowed for the reemergence of Chagas disease as an urban zoonosis in Venezuela and can propitiate the emergence of atypical T. lewisi infection in humans.


Assuntos
Insetos Vetores/parasitologia , Doenças dos Roedores/epidemiologia , Sifonápteros/parasitologia , Tripanossomíase/veterinária , Animais , Doença de Chagas/veterinária , DNA de Protozoário , Reservatórios de Doenças/parasitologia , Áreas de Pobreza , Ratos , Trypanosoma cruzi/genética , Trypanosoma lewisi/genética , Venezuela/epidemiologia , Zoonoses/transmissão
14.
Parasit Vectors ; 12(1): 424, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31522683

RESUMO

BACKGROUND: Trypanosoma cruzi, the protozoan agent of Chagas disease, is comprised of at least 6 genetic lineages (TcI-TcVI). Their geographical distribution, clinical associations and reservoir hosts are not fully elucidated, as genotyping is hampered due to the difficulty in isolating representative populations of organisms. Lineage-specific serological techniques may address these issues. METHODS: Trypanosoma cruzi lineage-specific serological assays were performed on human, canine, feline and armadillo sera from the Gran Chaco in northern Argentina, a region of ongoing transmission. Synthetic peptides representing lineage-specific epitopes of the trypomastigote small surface antigen (TSSA) were used in ELISA, and the TcII/V/VI shared epitope peptide (TSSApep-II/V/VI) was used in the Chagas Sero K-SeT rapid diagnostic test (RDT). RESULTS: Chagas Sero K-SeT RDT, using Protein G to detect human and canine IgG, was at least as sensitive as TSSApep-II/V/VI ELISA using specific secondary antibodies. For sera from humans TSSApep-II/V/VI seroprevalence by Chagas Sero K-SeT was 273/393 (69.5%), for dogs 48/73 (65.8%) and for armadillos 1/7 (14.3%); by ELISA for cats 5/19 (26.3%). The seroprevalence for humans was similar to that for Bolivian patients, amongst whom we previously observed an association of TSSApep-II/V/VI seropositivity with severity of cardiomyopathy. In humans, prevalence of TSSApep-II/V/VI recognition was associated with locality, and with increasing and decreasing age within the Qom and Creole populations, respectively. For dogs TSSApep-II/V/VI recognition was associated with being born before community-wide insecticide spraying (P = 0.05) and with Qom household (P < 0.001). CONCLUSIONS: We show here that Chagas Sero K-SeT RDT can replace ELISA for TSSApep-II/V/VI serology of humans and dogs; for humans there were statistically significant associations between a positive Chagas Sero K-SeT RDT and being resident in Area IV, and for dogs association with Qom household or with being born before the mass spraying campaign; we also show that with cats the TcII/V/VI epitope can be detected by ELISA. We assessed the lineage distribution in an unprecedented 83% of the human T. cruzi-seropositive population. These results form the basis for more detailed studies, enabling rapid in-the-field surveillance of the distribution and clustering of these lineages among humans and mammalian reservoirs of T. cruzi infection.


Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Testes Diagnósticos de Rotina/métodos , Sorogrupo , Testes Sorológicos/métodos , Trypanosoma cruzi/classificação , Animais , Argentina/epidemiologia , Tatus , Gatos , Doença de Chagas/parasitologia , Estudos Transversais , Cães , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Estudos Soroepidemiológicos , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação
15.
ACS Infect Dis ; 5(11): 1813-1819, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31538468

RESUMO

trans-Sialidase and cruzipain are important virulence factors from Trypanosoma cruzi, the etiological agent of Chagas disease, that have highly antigenic domains in their structure and were reported as potential tools for diagnosis of the illness. The aim of the present study is to assess the possibility of using cruzipain and the catalytic domain of trans-sialidase in a Surface Plasmon Resonance-based immunosensor for the diagnosis of chronic Chagas disease. Immunoassays carried out with canine sera verified that cruzipain allows the detection of anti-Trypanosoma cruzi antibodies whereas recombinant trans-sialidase did not yield specific detections, due to the high dilutions of serum used in the immunoassays that hinder the possibility to sense the specific low titer antibodies. The developed cruzipain-based biosensor, whose price per assay is comparable to a commercial enzyme-linked immunosorbent assay (ELISA), was successfully applied for the rapid quantification of specific antibodies against Trypanosoma cruzi in fresh human sera showing an excellent agreement with ELISA.


Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/diagnóstico , Doença de Chagas/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Trypanosoma cruzi/isolamento & purificação , Animais , Doença de Chagas/sangue , Doença de Chagas/parasitologia , Cisteína Endopeptidases/análise , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/imunologia , Doenças do Cão/sangue , Doenças do Cão/diagnóstico , Doenças do Cão/parasitologia , Cães , Glicoproteínas/análise , Glicoproteínas/genética , Glicoproteínas/imunologia , Humanos , Neuraminidase/análise , Neuraminidase/genética , Neuraminidase/imunologia , Proteínas de Protozoários/análise , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia , Fatores de Virulência/sangue , Fatores de Virulência/genética , Fatores de Virulência/imunologia
16.
Am J Trop Med Hyg ; 101(5): 1126-1134, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31549619

RESUMO

Surveillance of Chagas in the United States show more is known about prevalence in animals and vectors than in humans. Leveraging health information technology (HIT) may augment surveillance efforts for Chagas disease (CD), given its ability to disseminate information through health information exchanges (HIE) and geographical information systems (GISs). This systematic review seeks to determine whether technological tracking of Trypanosoma cruzi-infected domestic and/or sylvatic animals as sentinels can serve as a potential surveillance resource to manage CD in the southern United States. A Boolean search string was used in PubMed and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). Relevance of results was established and analysis of articles was performed by multiple reviewers. The overall Cohen statistic was 0.73, demonstrating moderate agreement among the study team. Four major themes were derived for this systematic review (n = 41): animals act as reservoir hosts to perpetuate CD, transmission to humans could be dependent on cohabitation proximity, variations in T. cruzi genotypes could lead to different clinical manifestations, and leveraging technology to track T. cruzi in domestic animals could reveal prevalent areas or "danger zones." Overall, our systematic review identified that HIT can serve as a surveillance tool to manage CD. Health information technology can serve as a surveillance tool to manage CD. This can be accomplished by tracking domestic and/or sylvatic animals as sentinels within a GIS. Information can be disseminated through HIE for use by clinicians and public health officials to reach at-risk populations.


Assuntos
Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Doença de Chagas/prevenção & controle , Doença de Chagas/veterinária , Vigilância de Evento Sentinela/veterinária , Animais , Doença de Chagas/epidemiologia , Humanos
17.
Ecohealth ; 16(3): 512-522, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31414319

RESUMO

Indigenous Mayangna and Miskitu inhabit Nicaragua's remote Bosawás Biosphere Reserve, located in the North Caribbean Coast Autonomous Region. They are sedentary horticulturists who supplement their diet with wild game, hunting with the assistance of dogs. To test whether hunting dogs increased the risk of human exposure to protozoal zoonotic neglected tropical diseases (NTDs), we sampled dogs from three communities varying in population size and level of contact with other communities. We screened dog feces (n = 58) for Giardia and Cryptosporidium DNA and sera (n = 78) for Trypanosoma cruzi antibodies and DNA. Giardia DNA was detected in 22% (13/58) of samples; sequencing revealed the presence of both zoonotic genotypes (assemblages A and B) and dog-specific genotypes (assemblages C and D). Giardia shedding was associated with community and age. Older dogs and those in the two, more accessible communities had greater odds of shedding parasites. Seroprevalence of T. cruzi antibodies, indicating prior exposure, was 9% (7/78). These results contribute to the limited literature on NTDs in indigenous populations, and suggest hunting dogs can both serve as sentinels of environmental NTDs and pose zoonotic risk for their owners and communities.


Assuntos
Doenças do Cão/epidemiologia , Cães/parasitologia , Animais de Estimação/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Fatores Etários , Animais , Doença de Chagas/veterinária , Criptosporidiose/epidemiologia , Cryptosporidium/genética , DNA de Protozoário , Fezes/parasitologia , Feminino , Giardia/genética , Giardíase/veterinária , Masculino , Nicarágua/epidemiologia , Estudos Soroepidemiológicos , Trypanosoma cruzi/genética
18.
J Am Vet Med Assoc ; 255(3): 317-329, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31298647

RESUMO

OBJECTIVE: To evaluate clinical, serologic, parasitological, and histologic outcomes of dogs with naturally occurring Trypanosoma cruzi infection treated for 12 months with amiodarone and itraconazole. ANIMALS: 121 dogs from southern Texas and southern Louisiana. PROCEDURES: Treatment group dogs (n = 105) received a combination of amiodarone hydrochloride (approx 7.5 mg/kg [3.4 mg/lb], PO, q 24 h, with or without a loading dosage protocol) and itraconazole (approx 10 mg/kg [4.5 mg/lb], PO, q 24 h, adjusted to maintain a plasma concentration of 1 to 2 µg/mL) for 12 months. Control group dogs (n = 16) received no antitrypanosomal medications. Serologic assays for anti-T cruzi antibodies, PCR assays for T cruzi DNA in blood, and physical evaluations were performed 1, 6, 9, 12, and 24 months after study initiation. Adverse events were recorded. Outcomes of interest were recorded and compared between groups. RESULTS: 86 of 105 treatment group dogs and 8 of 16 control group dogs survived and completed the study (5/19 and 6/7 deaths of treatment and control group dogs, respectively, were attributed to T cruzi infection). Mean survival time until death attributed to T cruzi was longer (23.19 vs 15.64 months) for the treatment group. Results of PCR assays were negative for all (n = 92) tested treatment group dogs (except for 1 dog at 1 time point) from 6 to 24 months after study initiation. Clinical improvement in ≥ 1 clinical sign was observed in 53 of 54 and 0 of 10 treatment and control group dogs, respectively; adverse drug events were minor and reversible. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested efficacy of this trypanocidal drug combination for the treatment of T cruzi infection in dogs.


Assuntos
Amiodarona , Doença de Chagas/veterinária , Doenças do Cão , Trypanosoma cruzi , Animais , Cães , Itraconazol , Louisiana , Texas
19.
J Vet Diagn Invest ; 31(5): 752-755, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31342874

RESUMO

A 9-y-old, zoo-housed, male red panda (Ailurus fulgens) became progressively lethargic and inappetent over a 1-wk period. Physical examination was unremarkable. A complete blood count showed mild normocytic, normochromic, non-regenerative anemia with the presence of trypomastigote organisms, consistent with a Trypanosoma sp. The organism was confirmed later as Trypanosoma cruzi lineage TcI via PCR and genome sequencing. The panda was initially treated supportively; however, its clinical status within 24 h from presentation deteriorated, and euthanasia was elected. Autopsy showed severe systemic T. cruzi infection with the presence of amastigotes in the heart, brain, peripheral nerves, skeletal muscles, tongue, liver, and testes. We used genome sequencing and serology in identifying the agent.


Assuntos
Ailuridae , Doença de Chagas/veterinária , Trypanosoma cruzi/isolamento & purificação , Animais , Animais de Zoológico , Doença de Chagas/diagnóstico , Doença de Chagas/parasitologia , Kansas , Masculino
20.
Vet Parasitol Reg Stud Reports ; 17: 100307, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31303214

RESUMO

A cross-sectional study was conducted to determine the prevalence of canine trypanosomiasis in an endemic community of Costa Rica. The indirect hemagglutination and indirect immunofluorescence assay yielded positive results in 6.4% (20/314) of canine samples analyzed; polymerase chain reaction (PCR) and light microscopy yielded positive results in one dog. Subsequently, a longitudinal study was carried out with 55 negative T. cruzi canines in the cross-sectional study. These dogs were divided into two groups: Group 1, which consisted of 25 individuals that lived in dwellings where triatomines were found in their homes; and Group 2, which consisted of 30 dogs that lived in dwellings where triatomines were not found during the previous study in their homes. Seroconversion occurred in six dogs (10.9%) in Group 1 in the first months of the year (dry season); these dogs remained seropositive until the end of the study. Only one of the six seropositive canines was also found positive once in T. cruzi PCR. The analysis of the amplified T. cruzi sequences of dogs and triatomines showed that all of them belonged to the TcI lineage. It is recommended that residents be made aware of the need to eliminate vectors in their homes and their surroundings.


Assuntos
Doença de Chagas/veterinária , Doenças do Cão/parasitologia , Doenças Endêmicas/veterinária , Insetos Vetores/parasitologia , Triatominae/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Costa Rica/epidemiologia , Estudos Transversais , DNA de Protozoário/sangue , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Cães , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Testes de Hemaglutinação/veterinária , Habitação/normas , Incidência , Estudos Longitudinais , Masculino , Microscopia de Fluorescência/veterinária , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Estações do Ano , Análise Espacial , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação , Zoonoses/parasitologia
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