RESUMEN
BACKGROUND: Vectorial transmission through hematophagous triatomine insects remains the primary mode of Chagas Disease contagion. These insects have become increasingly common in urban environments. Therefore, this study aimed to report an encounter of triatomines with trypanosomatid infection in a vertical residential condominium in Rio Branco, the capital of the state of Acre, in the western Brazilian Amazon. METHODS: Triatomines were collected from residents and sent to the municipality's Entomological Surveillance sector. Trypanosomatid positivity was evaluated using optical microscopy, followed by species and genotype identification using molecular biology techniques. RESULTS: Twenty-five adult triatomine specimens were collected from two of three condominium buildings invading apartments from the 2nd to 13th floors. Six specimens were identified as Rhodnius sp. and 19 as R. montenegrensis. Among these, molecular tests were conducted on seven specimens, with five testing positive for Trypanosoma cruzi, all belonging to genotype TcI. CONCLUSIONS: These findings underscore the need for further studies to better understand the invasive capacity of these insects in these environments and the mechanisms involved in this process.
Asunto(s)
Enfermedad de Chagas , Insectos Vectores , Rhodnius , Trypanosoma cruzi , Animales , Brasil , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/transmisión , Rhodnius/clasificación , Rhodnius/genética , Rhodnius/parasitología , Genotipo , Vivienda , HumanosRESUMEN
Chagas disease, caused by Trypanosoma cruzi, affects millions of people globally and is associated with significant underdiagnosis and undertreatment. Current diagnostic algorithms face challenges in remote regions. We aimed to review the potential of rapid diagnostic tests (RDTs) for screening or diagnosing chronic Chagas disease in endemic areas. An expert panel representing scientific and academic institutions from the Americas convened with the aim of discussing the use of RDTs. The study employed the nominal group technique, gathering insights from diverse experts during a 3-day meeting. Panel discussions covered RDT application, research protocols, and regulatory mechanisms. The results indicate that RDTs play a crucial role in surveillance and screening, although limitations in sensitivity and specificity exist. The expert group recommends standardized protocols, emphasizes the importance of cost-effectiveness assessments, and highlights the need to consider geographic validation. Despite these challenges, RDTs present a promising avenue for improving Chagas disease diagnosis in resource-limited settings. Future research and a collaborative approach are deemed essential for effective implementation.
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Enfermedad de Chagas , Pruebas Diagnósticas de Rutina , Trypanosoma cruzi , Enfermedad de Chagas/diagnóstico , Humanos , Pruebas Diagnósticas de Rutina/métodos , Trypanosoma cruzi/aislamiento & purificación , Enfermedad Crónica , Sensibilidad y Especificidad , Prueba de Diagnóstico RápidoRESUMEN
BACKGROUND: The Gran Chaco ecoregion is a well-known hotspot of several neglected tropical diseases (NTDs) including Chagas disease, soil-transmitted helminthiasis and multiparasitic infections. Interspecific interactions between parasite species can modify host susceptibility, pathogenesis and transmissibility through immunomodulation. Our objective was to test the association between human co-infection with intestinal parasites and host parasitaemia, infectiousness to the vector and immunological profiles in Trypanosoma cruzi-seropositive individuals residing in an endemic region of the Argentine Chaco. METHODS: We conducted a cross-sectional serological survey for T. cruzi infection along with an intestinal parasite survey in two adjacent rural villages. Each participant was tested for T. cruzi and Strongyloides stercoralis infection by serodiagnosis, and by coprological tests for intestinal parasite detection. Trypanosoma cruzi bloodstream parasite load was determined by quantitative PCR (qPCR), host infectiousness by artificial xenodiagnosis and serum human cytokine levels by flow cytometry. RESULTS: The seroprevalence for T. cruzi was 16.1% and for S. stercoralis 11.5% (n = 87). We found 25.3% of patients with Enterobius vermicularis. The most frequent protozoan parasites were Blastocystis spp. (39.1%), Giardia lamblia (6.9%) and Cryptosporidium spp. (3.4%). Multiparasitism occurred in 36.8% of the examined patients. Co-infection ranged from 6.9% to 8.1% for T. cruzi-seropositive humans simultaneously infected with at least one protozoan or helminth species, respectively. The relative odds of being positive by qPCR or xenodiagnosis (i.e. infectious) of 28 T. cruzi-seropositive patients was eight times higher in people co-infected with at least one helminth species than in patients with no such co-infection. Trypanosoma cruzi parasite load and host infectiousness were positively associated with helminth co-infection in a multiple regression analysis. Interferon-gamma (IFN-γ) response, measured in relation to interleukin (IL)-4 among humans infected with T. cruzi only, was 1.5-fold higher than for T. cruzi-seropositive patients co-infected with helminths. The median concentration of IL-4 was significantly higher in T. cruzi-seropositive patients with a positive qPCR test than in qPCR-negative patients. CONCLUSIONS: Our results show a high level of multiparasitism and suggest that co-infection with intestinal helminths increased T. cruzi parasitaemia and upregulated the Th2-type response in the study patients.
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Enfermedad de Chagas , Coinfección , Helmintiasis , Parasitosis Intestinales , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/inmunología , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Coinfección/parasitología , Coinfección/epidemiología , Coinfección/inmunología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/complicaciones , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/sangre , Enfermedad de Chagas/inmunología , Animales , Adulto , Estudios Transversales , Masculino , Femenino , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Parasitosis Intestinales/complicaciones , Parasitosis Intestinales/inmunología , Persona de Mediana Edad , Helmintiasis/complicaciones , Helmintiasis/parasitología , Helmintiasis/epidemiología , Helmintiasis/inmunología , Adulto Joven , Adolescente , Argentina/epidemiología , Estudios Seroepidemiológicos , Strongyloides stercoralis/inmunología , Strongyloides stercoralis/aislamiento & purificación , Parasitemia/parasitología , Parasitemia/epidemiología , Células Th2/inmunología , Niño , Estrongiloidiasis/epidemiología , Estrongiloidiasis/parasitología , Estrongiloidiasis/complicaciones , Estrongiloidiasis/inmunología , Estrongiloidiasis/sangre , Anciano , Citocinas/sangre , Anticuerpos Antiprotozoarios/sangreRESUMEN
Background: Chagas disease or American trypanosomiasis, caused by Trypanosoma cruzi and vectored by triatomines, affects millions of people worldwide. In endemic countries including Mexico, infections in domestic animals, such as dogs, may affect the risk of human disease when they serve as a source of infection to vectors that subsequently infect humans. Materials and Methods: We conducted a cross-sectional study of 296 dogs from two cities near the northern and southern borders of Mexico: Reynosa, Tamaulipas, and Tuxtla Gutierrez, Chiapas. Infection was measured based on testing of blood using T. cruzi quantitative PCR (qPCR) and up to three antibody detection assays. The StatPak immunochromatographic assay was used to screen samples and the indirect fluorescent antibody (IFA) and multiplex microsphere immunoassay (MIA) tests were used as secondary tests on all samples that screened positive and a subset of negatives. Serologic positivity was defined based on reactivity on at least two independent tests. Results: Of the 280 samples tested for parasite DNA, two (0.7%) were positive, one of which (0.4%) was confirmed as T. cruzi discrete typing unit TcIV. Overall, 72 (24.3%) samples were reactive for T. cruzi antibodies via StatPak of which 8 were also positive using MIA and 2 were also positive using IFA (including one of the PCR-positive dogs). Overall, nine dogs (3.4%) met study criteria of positivity based on either/both serology or PCR tests. Positive dogs were found in both regions of Mexico; five (2.7%) from Reynosa and four (3.6%) from Tuxtla Gutierrez. We found no association between infection status and state of origin, sex, age group, breed group, neighborhood, and whether other pets lived in the home. Conclusion: Our results re-emphasize dogs' utility as sentinels for T. cruzi in Mexico and underscore the need for improved veterinary diagnostic tests and parasite surveillance at the household level in endemic countries.
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Enfermedad de Chagas , Enfermedades de los Perros , Trypanosoma cruzi , Animales , Perros , Enfermedad de Chagas/veterinaria , Enfermedad de Chagas/epidemiología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Trypanosoma cruzi/aislamiento & purificación , Trypanosoma cruzi/genética , México/epidemiología , Estudios Transversales , Masculino , Femenino , Anticuerpos Antiprotozoarios/sangreRESUMEN
BACKGROUND: Vertical transmission of Trypanosoma cruzi represents approximately 20% of new Chagas disease cases. Early detection and treatment for women of childbearing age and newborns is a public health priority, but the lack of a simple and reliable diagnostic test remains a major barrier. We aimed to evaluate the performance of a point-of-care loop-mediated isothermal amplification (LAMP) assay for the detection of T cruzi. METHODS: In this proof-of-concept study, we coupled a low-cost 3D printer repurposed for sample preparation and amplification (PrintrLab) to the Eiken T cruzi-LAMP prototype to detect vertically transmitted T cruzi, which we compared with standardised PCR and with the gold-standard algorithm (microscopy at birth and 2 months and serological study several months later). We screened pregnant women from two hospitals in the Bolivian Gran Chaco province, and those who were seropositive for T cruzi were offered the opportunity for their newborns to be enrolled in the study. Newborns were tested by microscopy, LAMP, and PCR at birth and 2 months, and by serology at 8 months. FINDINGS: Between April 23 and Nov 17, 2018, 986 mothers were screened, among whom 276 were seropositive for T cruzi (28·0% prevalence, 95% CI 25·6-31·2). In total, 224 infants born to 221 seropositive mothers completed 8 months of follow-up. Congenital transmission was detected in nine of the 224 newborns (4·0% prevalence, 1·9-7·5) by direct microscopy observation, and 14 more cases were diagnosed serologically (6·3%, 3·6-10·3), accounting for an overall vertical transmission rate of 10·3% (6·6-15·0; 23 of 224). All microscopy-positive newborns were positive by PrintrLab-LAMP and by PCR, while these techniques respectively detected four and five extra positive cases among the remaining 215 microscopy-negative newborns. INTERPRETATION: The PrintrLab-LAMP yielded a higher sensitivity than microscopy-based analysis. Considering the simpler use and expected lower cost of LAMP compared with PCR, our findings encourage its evaluation in a larger study over a wider geographical area. FUNDING: Inter-American Development Bank.
Asunto(s)
Enfermedad de Chagas , Transmisión Vertical de Enfermedad Infecciosa , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Trypanosoma cruzi , Humanos , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/parasitología , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Recién Nacido , Bolivia/epidemiología , Femenino , Embarazo , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular/métodos , Prueba de Estudio Conceptual , Sensibilidad y Especificidad , AdultoRESUMEN
BACKGROUND: It is unknown whether lymphopenia is a risk factor for the reactivation of Chagas disease in heart transplantation (HTx), as recently described in the reactivation of cytomegalovirus in transplant patients. OBJECTIVE: To evaluate whether lymphopenia in the perioperative period of heart transplantation is related to early Trypanosoma cruzi parasitemia. METHODS: This observational, retrospective study analyzed a sample from January 2014 to January 2023). Parasitemia was evaluated in the first 3 months after HTx using serum polymerase chain reaction (PCR) and compared with the total lymphocyte count in the perioperative period of HTx using receiver operating characteristic curves. Baseline characteristics were compared with PCR for Chagas using independent Cox proportional hazards models. A significance level of 5% was adopted. RESULTS: The sample (n = 35) had a mean age of 52.5 ± 8.1 years, and 22 patients (62.8%) had positive PCR for Chagas. The mean lowest lymphocyte values in the first 14 days after HTx were 398 ± 189 and 755 ± 303 cells/mm3 in patients with and without parasitemia, respectively, within 3 months after HTx (area under the curve = 0.857; 95% confidence interval: 0.996 to 0.718, sensitivity and specificity of 83.3% and 86.4%). A cutoff value of less than 550 lymphocytes/mm3 was determined as a risk factor for the presence of parasitemia. Patients with lymphocytes < 550 units/mm3 in the first 14 days after HTx presented positive PCR in 80% of cases. For every increase of 100 lymphocytes/mm3, the risk of PCR positivity was reduced by 26% (hazard rate ratio = 0.74; 95% confidence interval: 0.59 to 0.93, p = 0.009). CONCLUSION: There was an association between lymphopenia in the perioperative period of HTx and early T. cruzi parasitemia detected by PCR.
FUNDAMENTO: É desconhecido se a linfopenia é fator de risco para a reativação da doença de Chagas no transplante cardíaco (TxC), como recentemente descrito na reativação de citomegalovírus em pacientes transplantados. OBJETIVO: Avaliar se a linfopenia no perioperatório do TxC está relacionada à parasitemia precoce pelo Trypanosoma cruzi. MÉTODOS: Amostra analisada (janeiro de 2014 a janeiro de 2023) em estudo observacional e retrospectivo. A parasitemia foi avaliada nos primeiros 3 meses após o TxC por meio da reação em cadeia da polimerase sérica (PCR) e comparada com a contagem total de linfócitos no perioperatório do TxC por curvas ROC. Comparadas características de base com a PCR Chagas por modelos de risco proporcionais de Cox independentes. Nível de significância adotado de 5%. RESULTADOS: Amostra (n = 35) apresentou idade média de 52,5 ± 8,1 anos e PCR Chagas positiva em 22 pacientes (62,8%). As médias dos menores valores de linfócitos nos primeiros 14 dias do TxC foram 398 ± 189 e 755 ± 303 células/mm3 em pacientes com e sem parasitemia nos 3 meses após o TxC, respectivamente (área sob a curva = 0,857; intervalo de confiança de 95%: 0,996 a 0,718, sensibilidade e especificidade de 83,3% e 86,4%). Determinado valor de corte inferior a 550 linfócitos/mm3 como fator de risco para presença de parasitemia. Pacientes com linfócitos < 550 unidades/mm3 nos primeiros 14 dias do pós-TxC apresentaram PCR positiva em 80% dos casos. Para cada aumento de 100 linfócitos/mm3, o risco de positividade da PCR é reduzido em 26% (razão de riscos = 0,74; intervalo de confiança de 95%: 0,59 a 0,93, p = 0,009). CONCLUSÃO: Houve associação entre a linfopenia no perioperatório do TxC com a parasitemia precoce pelo T. cruzi detectada por PCR.
Asunto(s)
Enfermedad de Chagas , Trasplante de Corazón , Linfopenia , Parasitemia , Reacción en Cadena de la Polimerasa , Trypanosoma cruzi , Humanos , Trasplante de Corazón/efectos adversos , Masculino , Persona de Mediana Edad , Femenino , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Estudios Retrospectivos , Recuento de Linfocitos , Enfermedad de Chagas/complicaciones , Reacción en Cadena de la Polimerasa/métodos , Adulto , Factores de Riesgo , Factores de Tiempo , Valor Predictivo de las Pruebas , Cardiomiopatía Chagásica/cirugía , Cardiomiopatía Chagásica/sangre , Curva ROCRESUMEN
INTRODUCTION: Chagas disease caused by Trypanosoma cruzi (T cruzi) found in the Americas is often missed during the early stage of infection due to lack of sensitive diagnostic tests. The classic immunological and parasitological tests often fail in the acute phase due to the nonspecific and low antibody level nature of the infection and in the chronic phase due to low levels of trypanosomes in the blood. For successful control strategies, there must be a sensitive and specific diagnostic test. OBJECTIVE/METHODS: We have demonstrated the possibility (proof of concept) of detecting T cruzi-specific repeat DNA via polymerase chain reaction (PCR) by (1) spiking 15 urine samples collected from volunteers free of prior infection with 3 different concentrations of T cruzi (3 strains), Trypanosoma brucei, and Trypanosoma rhodesiense (African strain) genomic DNA and (2) from filtered collected clinical samples from Argentina. Three sets of primers were used. RESULTS: Our approach detected repeat DNA specific for T cruzi strains from 1 clinical sample by 2 sets of primer and from spiked urine by all 3 sets of primer but not the African species. A serial dilution (spiking) also was performed on T cruzi strains to detect sensitivities of the assay. One set of primers constantly detected satellite DNA for all T cruzi strains from 70 pg/µl to 175 fg/µl. CONCLUSIONS: We were able to demonstrate the feasibility of detecting T cruzi-specific DNA from filtered urine samples by sensitive and specific PCR assay. Besides the evident increased sensitivity and specificity of primers, our approach can be used to explore Chagas prevalence in endemic areas - especially in congenital Chagas newborn screening - and in the acute phase.
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Enfermedad de Chagas , ADN Protozoario , Reacción en Cadena de la Polimerasa , Trypanosoma cruzi , Humanos , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/orina , ADN Protozoario/orina , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Sensibilidad y Especificidad , Argentina/epidemiología , Especificidad de la EspecieRESUMEN
BACKGROUND: Habitat modification and land use changes impact ecological interactions and alter the relationships between humans and nature. Mexico has experienced significant landscape modifications at the local and regional scales, with negative effects on forest cover and biological biodiversity, especially in the Yucatan peninsula in southeastern Mexico. Given the close relationship between landscape modification and the transmission of zoonotic and vector-borne diseases, it is essential to develop criteria for identifying priority zoonoses in the south of the country. METHODOLOGY/PRINCIPAL FINDINGS: We reviewed 165 published studies on zoonotic and vector-borne diseases in the region (2015-2024). We identified the most frequent vectors, reservoirs, and hosts, the most prevalent infections, and the factors associated with transmission risk and the anthropogenic landscape modification in urban, rural, ecotone, and sylvatic habitats. The most relevant pathogens of zoonotic risk included Trypanosoma cruzi, arboviruses, Leishmania, Rickettsia, Leptospira, and Toxoplasma gondii. Trypanosoma cruzi was the vector-borne agent with the largest number of infected vertebrate species across habitats, while Leishmania and arboviruses were the ones that affected the greatest number of people. Dogs, cats, backyard animals, and their hematophagous ectoparasites are the most likely species maintaining the transmission cycles in human settlements, while rodents, opossums, bats, and other synanthropic animals facilitate connection and transmission cycles between forested habitats with human-modified landscapes. Pathogens displayed different prevalences between the landscapes, T. cruzi, arbovirus, and Leptospira infections were the most prevalent in urban and rural settlements, whereas Leishmania and Rickettsia had similar prevalence across habitats, likely due to the diversity and abundance of the infected vectors involved. The prevalence of T. gondii and Leptospira spp. may reflect poor hygiene conditions. Additionally, results suggest that prevalence of zoonotic and vector-borne diseases is higher in deforested areas and agricultural aggregates, and in sites with precarious health and infrastructure services. CONCLUSIONS: Some hosts, vectors, and transmission trends of zoonotic and vector-borne diseases in the YP are well known but others remain poorly recognized. It is imperative to reinforce practices aimed at increasing the knowledge, monitoring, prevention, and control of these diseases at the regional level. We also emphasize the need to perform studies on a larger spatio-temporal scale under the socio-ecosystem perspective, to better elucidate the interactions between pathogens, hosts, vectors, environment, and sociocultural and economic aspects in this and many other tropical regions.
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Enfermedades Transmitidas por Vectores , Zoonosis , Animales , Humanos , Zoonosis/transmisión , Zoonosis/epidemiología , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/epidemiología , Prevalencia , México/epidemiología , Ecosistema , Trypanosoma cruzi/aislamiento & purificación , Vectores de Enfermedades , Reservorios de Enfermedades/microbiología , Leptospira/aislamiento & purificación , Leptospira/genética , Leptospira/clasificación , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/epidemiología , Toxoplasma , Arbovirus/fisiología , Leishmania/aislamiento & purificación , Leishmaniasis/transmisión , Leishmaniasis/epidemiologíaRESUMEN
Triatomine bugs are vectors of Trypanosoma cruzi, the etiologic agent of Chagas disease in the American continent. Here, we have tested a loop-mediated isothermal amplification (LAMP) test for a direct detection of T. cruzi in feces of Triatoma infestans, the main vector of this parasite in the Southern Cone of America. The analytical evaluation showed positive results with samples of triatomine feces artificially inoculated with DNA from strains of T. cruzi corresponding to each Discrete Typing Units (I-VI), with a sensitivity of up to one parasite per reaction. Conversely, the reaction yielded negative results when tested with DNA from Trypanosoma rangeli and other phylogenetically related and unrelated organisms. In triatomines captured under real field conditions (from urban households), and defined as positive or negative for T. cruzi using the reference microscopy technique, the LAMP test achieved a concordance of 100 %. Our results demonstrate that this LAMP reaction exhibits excellent analytical specificity and sensitivity without interference from the fecal matrix, since all the reactions were conducted without purification steps. This simple molecular diagnostic technique can be easily used by vector control agencies under field conditions.
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Enfermedad de Chagas , Heces , Insectos Vectores , Técnicas de Amplificación de Ácido Nucleico , Triatoma , Trypanosoma cruzi , Animales , Heces/parasitología , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/diagnóstico , Triatoma/parasitología , Técnicas de Amplificación de Ácido Nucleico/métodos , Insectos Vectores/parasitología , Sensibilidad y Especificidad , Técnicas de Diagnóstico MolecularRESUMEN
The presence of Trypanosoma cruzi vectors in urban areas has been frequent, with colonization of homes and associated with reservoir animals that increase risk to humans, with simultaneous circulation of vectors and T. cruzi. The study aimed to describe the circulation of triatomines and T. cruzi in the Metropolitan Region of São Paulo, as well as evaluate risk situations. For analysis purposes, the triatomine notification information from January 2016 to July 2023 was used. While for Didelphis sp. collection with the aid of traps, notification information used was from 2019 to 2023. Information about triatomines came from spontaneous demand by the population and notification services were carried out by state field teams following defined protocols. 202 notifications were received with the capture of 448 triatomines. The positivity for T. cruzi observed was 60.5%. Regarding Didelphis sp., 416 animals were collected, 5.3% of which were positive for T. cruzi. There was overlapping areas of presence of infected triatomines and Didelphis sp., whose Discrete Typing Unit (DTU) was T. cruzi I. This work indicates the presence of infected vectors in urban areas, and the presence of a wild cycle of T. cruzi in didelphiids, reaffirming the need for and importance of vector surveillance work, through actions that can prevent the transmission of Chagas disease.
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Enfermedad de Chagas , Didelphis , Insectos Vectores , Trypanosoma cruzi , Animales , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/veterinaria , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/parasitología , Brasil/epidemiología , Insectos Vectores/parasitología , Medición de Riesgo , Didelphis/parasitología , Triatominae/parasitología , Ciudades , HumanosRESUMEN
We aimed to measure the association between Trypanosoma cruzi infection in pregnancy and reduced fetal growth in the absence of T. cruzi congenital transmission. We conducted a cross-sectional study of secondary data of all singleton live births between 2011 and 2013 in five hospitals from Argentina, Honduras, and Mexico. We excluded newborns with T. cruzi infection. Noninfected pregnant people were those without any positive rapid tests. The main study outcomes were birth weight, head circumference, and length for gestational age and sex. Logistic regression models were adjusted for country, age, education level, and obstetric history. Of the 26,544 deliveries, 459 (1.7%) pregnant people were found by rapid tests to be positive for T. cruzi. Of these, 320 were positive by enzyme-linked immunosorbent assay and 231 had a positive polymerase chain reaction (PCR) test. Uninfected newborns from T. cruzi-infected pregnant people were more likely to have birth weights below the 5th and 10th percentiles and head circumferences below the 3rd and 10th percentiles. Among T. cruzi-infected pregnant people diagnosed by PCR, the odds ratios were 1.58 for birth weight below the 10th percentile (95% CI, 1.12-2.23) and 1.57 for birth weight below the 5th percentile (95% CI, 1.02-2.42). Higher T. cruzi parasitic loads in pregnancy had a stronger association with reduced fetal growth (both in birth weight and head circumference), with an odds ratio of 2.31 (95% CI, 1.36-3.91) for a birth weight below the 5th percentile. The association shows, irrespective of causality, that newborns of pregnancies with T. cruzi have an increased risk of reduced fetal growth. We recommend further studies to assess other potential confounders and the causality of these associations.
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Peso al Nacer , Enfermedad de Chagas , Trypanosoma cruzi , Humanos , Femenino , Embarazo , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/congénito , Estudios Transversales , Honduras/epidemiología , Argentina/epidemiología , Trypanosoma cruzi/aislamiento & purificación , Adulto , México/epidemiología , Recién Nacido , Complicaciones Parasitarias del Embarazo/epidemiología , Masculino , Adulto Joven , Retardo del Crecimiento Fetal/epidemiología , Retardo del Crecimiento Fetal/parasitología , Desarrollo FetalRESUMEN
Background: Marsupials and rodents are the most important wild and synanthropic hosts of Trypanosoma cruzi due to the high frequency of infection, maintenance of diverse genetic populations of the parasite, and their close proximity to interact with both transmission cycles, sylvatic and peridomestic. Our aim was to identify the discrete typing units (DTU) of T. cruzi from different wild and synanthropic hosts in two regions of Mexico and to carry out a review of historical data focusing on current knowledge on the diversity and T. cruzi DTUs of host species. Materials and Methods: One hundred fifteen samples were obtained from two areas in Tabasco and Nayarit state. The presence of T. cruzi was evaluated by PCR. Results: The 12.6% (12/95) of samples from Tabasco and 65% (13/20) from Nayarit were found to be positive for parasite DNA. All the sequences analyzed were grouped in T. cruzi DTU I; low nucleotide diversity was observed in Tabasco (π = 0.00566, and Ï´ = 0.00632), while high genetic diversity was observed in Nayarit sequences, up to 8.63 (π) to 11.10 (Ï´) times greater than Tabasco sequences. Genetic flow and migration between Tabasco, and Nayarit were scarce (FST = 0.37329 and Nm = 0.42), and genetic exchange was observed only between nearby areas. The bibliographic review of hosts in Mexico, together with our data, shows a heterogeneous T. cruzi prevalence in Chiroptera and domestic animals. For Atelidae and Canids, prevalence is generally below 25%. However, a high prevalence, greater than 25% and up to 100%, was recorded in Didelphimorphia, and Rodentia. Few studies in regions of Mexico have been described as infected with the parasite; in these, the genetic group with the highest prevalence is the DTU I. Conclusion: Marsupials and rodents are important reservoirs of T. cruzi; DTU I was frequently reported; however, recent genetic and reservoir studies have demonstrated the presence of greater diversity of genetic groups.
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Enfermedad de Chagas , Trypanosoma cruzi , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Trypanosoma cruzi/clasificación , Animales , México/epidemiología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/veterinaria , Enfermedad de Chagas/transmisión , Animales Salvajes/parasitología , Mamíferos/parasitología , Variación Genética , Roedores/parasitologíaRESUMEN
The Mexican free-tailed bat (Tadarida brasiliensis) is one of the most abundant mammals in North America. Mexican free-tailed bats have a wide geographic range stretching from northern South America to the western United States. Bats are theorized to be the original hosts for Trypanosoma cruzi -the causative agent of Chagas disease- and can serve as a source of infection to triatomine insect vectors that feed upon them. Chagas disease is a neglected tropical disease across the Americas where triatomines are present, including the southern United States, where Texas reports this highest number of locally-acquired human cases. To learn more about the role of bats in the ecology of Chagas disease in Texas, we surveyed a colony of Mexican free-tailed bats from Brazos County, Texas, for T. cruzi using carcasses salvaged after an extreme weather event. A total of 283 Mexican free-tailed bats collected in February 2021 were dissected and DNA from the hearts and kidneys was used for T. cruzi detection via qPCR. None of the bat hearts or kidneys tested positive for T. cruzi; this sample size affords 95% confidence that the true prevalence of T. cruzi in this population does not exceed 1%. Future sampling of multiple bat species as well as migrant and resident colonies of Mexican free-tailed bats across different times of the year over a broader geographic range would be useful in learning more about the role of bats in the ecology of Chagas disease in Texas.
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Enfermedad de Chagas , Quirópteros , Trypanosoma cruzi , Animales , Quirópteros/parasitología , Texas/epidemiología , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/veterinaria , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/parasitología , Masculino , FemeninoRESUMEN
Currently, approximately 70% of new cases of Chagas disease (CD) in Brazil are attributed to oral transmission, particularly through foods such as açaí, bacaba, and sugarcane juice, primarily in the northern and northeastern regions of the country. This underscores the imperative need to control the spread of the disease. The methods utilized to conduct quality control for food associated with outbreaks and to assess the potential for the oral transmission of CD through consuming açaí primarily rely on isolating the parasite or inoculating food into experimental animals, restricting the analyses to major research centers. While there are existing studies in the literature on the detection and quantification of T. cruzi DNA in açaí, the evaluation of parasites' viability using molecular methods in this type of sample and differentiating between live and dead parasites in açaí pulp remain challenging. Consequently, we developed a molecular methodology based on RT-qPCR for detecting and quantifying viable T. cruzi in açaí pulp samples. This protocol enables the stabilization and preservation of nucleic acids in açaí, along with incorporating an exogenous internal amplification control. The standardization of the RNA extraction method involved a simple and reproducible approach, coupled with a one-step RT-qPCR assay. The assay underwent validation with various T. cruzi DTUs and demonstrated sensitivity in detecting up to 0.1 viable parasite equivalents/mL in açaí samples. Furthermore, we investigated the effectiveness of a bleaching method in eliminating viable parasites in açaí samples contaminated with T. cruzi by comparing the detection of DNA versus RNA. Finally, we validated this methodology using açaí pulp samples positive for T. cruzi DNA, which were collected in a municipality with a history of oral CD outbreaks (Coari-AM). This validation involved comparing the detection and quantification of total versus viable T. cruzi. Collectively, our findings demonstrate the feasibility of this methodology in detecting viable forms of T. cruzi in açaí pulp samples, emerging as a crucial tool for monitoring oral outbreaks of Chagas disease resulting from açaí consumption.
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Enfermedad de Chagas , Trypanosoma cruzi , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/diagnóstico , Animales , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Euterpe , Brasil/epidemiología , Humanos , ADN Protozoario/genéticaRESUMEN
In July and October 2023, two live triatomine bugs were found inside a home in New Castle County, Delaware. The bugs were identified as Triatoma sanguisuga, the most widespread triatomine bug species in the United States. Triatoma sanguisuga is a competent vector of Trypanosoma cruzi, the causative agent of Chagas disease. The two specimens were tested via real-time PCR (qPCR) for infection with T. cruzi, and one of the specimens was positive. Despite T. sanguisuga being endemic to the area, attainment of accurate species identification and T. cruzi testing of the bugs required multiple calls to federal, state, private, and academic institutions over several months. This constitutes the first report of T. sanguisuga infected with T. cruzi in Delaware. In addition, this is the first published report of T. sanguisuga in New Castle County, the northernmost and most densely populated county in Delaware. New Castle County still conforms to the described geographic range of T. sanguisuga, which spans from Texas to the East Coast of the United States. The T. cruzi infection prevalence of the species has not been studied in the northeastern United States, but collections in southern states have found prevalences as high as 60%. The Delaware homeowner's lengthy pursuit of accurate information about the vector highlights the need for more research on this important disease vector in Delaware.
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Enfermedad de Chagas , Insectos Vectores , Triatoma , Trypanosoma cruzi , Animales , Triatoma/parasitología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/transmisión , Delaware/epidemiología , Trypanosoma cruzi/aislamiento & purificación , Trypanosoma cruzi/genética , Insectos Vectores/parasitología , HumanosRESUMEN
Background: Different pathogens can cause dilated cardiomyopathy, one of them is Trypanosoma cruzi protozoan. T.cruzi-chronic infection causes chronic Chagasic cardiomyopathy and affects the sinus node and the conduction systembelow the bundle of His; besides, it shows excellent arrhythmogenic potential because of ventricular arrhythmias. Knowingthe clinical characteristics and performing serological tests to diagnose chronic Chagasic cardiomyopathy is essential. The serological diagnosis for searching the antibodies is based on the phase, which can be a predictor for the development of dilated cardiomyopathy. Objectives: In this work, the objective was to describe the frequency of dilated cardiomyopathy in patients with T. cruzi positive serology. Method: A total of 961 patients who were medically and clinically diagnosed with dilated cardiomyopathy were studied. Of these, 128 were diagnosed with chronic Chagasic cardiomyopathy and had positive serology for T. cruzi with two serological tests. Results: The clinical findings were obtained from the results of the electrocardiograms and were taken from the patient's clinical histories. Conclusion: In conclusion, complete blockage of the right branch of the bundle of His (44.2%) is one of the primary conduction disorders in the patients studied. Regarding seroprevalence, 14% of patients diagnosed with dilated cardiomyopathy had anti-T. cruzi antibodies.
Antecedentes: La cardiomiopatía dilatada puede ser causada por diferentes patógenos y uno de ellos es el protozoario Trypanosoma cruzi. La infección crónica causa la cardiomiopatía chagásica crónica, que afecta el nódulo sinusal y el sistema de conducción a nivel del haz de His; además, muestra gran potencial arritmogénico, ya que frecuentemente se presentan arritmias ventriculares. Para diagnosticar la cardiomiopatía chagásica crónica es indispensable conocer las características clínicas y realizar los ensayos serológicos. El diagnóstico serológico para la búsqueda de anticuerpos se basa en la fase de la enfermedad en la que se encuentre el individuo, los cuales pueden ser un predictor para el desarrollo de la cardiomiopatía dilatada. Objetivo: El objetivo de nuestro trabajo fue describir la frecuencia de cardiomiopatía dilatada en pacientes con serología positiva a T. cruzi en el Instituto Nacional de Cardiología Ignacio Chávez. Método: Se estudiaron 961 pacientes que fueron diagnosticados médica y clínicamente con cardiomiopatía dilatada y, de estos, 128 fueron diagnosticados con cardiomiopatía chagásica crónica, los cuales presentaban serología positiva a T. cruzi con dos pruebas serológicas. Resultados: Los hallazgos clínicos se obtuvieron de los resultados de los electrocardiogramas y fueron tomados de las historias clínicas de los pacientes. Conclusiones: En conclusión, el bloqueo completo de la rama derecha del haz de His (44.2%) es una de las principales alteraciones de la conducción en los pacientes estudiados. Con respecto a la seroprevalencia, el 14% de los pacientes con diagnóstico de cardiomiopatía dilatada tuvieron anticuerpos anti-T. cruzi.
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Academias e Institutos , Cardiomiopatía Chagásica , Humanos , Masculino , Femenino , Persona de Mediana Edad , Cardiomiopatía Chagásica/epidemiología , Cardiomiopatía Chagásica/diagnóstico , Estudios Seroepidemiológicos , México/epidemiología , Adulto , Factores de Tiempo , Anciano , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/diagnóstico , Cardiomiopatía Dilatada/epidemiología , Trypanosoma cruzi/inmunología , Trypanosoma cruzi/aislamiento & purificación , Adulto JovenRESUMEN
PURPOSE: Trypanosoma cruzi and Leishmania spp. coexist in several endemic areas, and there are few studies of Chagas disease and leishmaniasis coinfection worldwide; for this reason, the objective of this work was to determine the Chagas disease and leishmaniasis coinfection in several rural communities co-endemic for these diseases. METHODS: A total of 1107 human samples from six co-endemic rural communities of Cojedes state, Venezuela, were analyzed. Serum samples were evaluated by ELISA, indirect hemagglutination, and indirect immunofluorescence for Chagas disease diagnosis, and individuals were evaluated for leishmaniasis by leishmanin skin test (LST). Approximately, 30% of the individuals were also analyzed by PCR (blood clot samples) for T. cruzi and for Leishmania spp. RESULTS: The 14.7% of the individuals were positive to Trypanosoma cruzi infection by serology, and 25.8% were positive to Leishmania spp. current or past infection by LST. Among the group with PCR results, 7.8% were positive for T. cruzi, and 9.4% for Leishmania spp. The coinfection T. cruzi/Leishmania spp. was 6.5%. The T. cruzi DTUs of the positive blood clot samples were TcI, revealed using the molecular markers: (i) intergenic region of the miniexon, (ii) D7 divergent domain of the 24Sα rDNA, (iii) size-variable domain of the 18S rDNA, and (iv) hsp60-PCR-RFLP (EcoRV). The Leishmania species identified were L. (Leishmania) mexicana and L. (Viannia) braziliensis. CONCLUSION: A high prevalence was found for T. cruzi and Leishmania spp. single and coinfections in almost all communities studied, being these results of relevance for the implementation of control programs in co-endemic areas.
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Enfermedad de Chagas , Coinfección , Leishmania , Leishmaniasis , Población Rural , Trypanosoma cruzi , Humanos , Venezuela/epidemiología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/parasitología , Coinfección/parasitología , Coinfección/epidemiología , Leishmaniasis/epidemiología , Leishmaniasis/parasitología , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Adulto , Adolescente , Masculino , Niño , Femenino , Persona de Mediana Edad , Adulto Joven , Animales , Leishmania/genética , Leishmania/aislamiento & purificación , Leishmania/clasificación , Preescolar , Zoonosis/parasitología , Zoonosis/epidemiología , Anciano , Reacción en Cadena de la Polimerasa , Anticuerpos Antiprotozoarios/sangre , Lactante , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
Trypanosoma cruzi is a digenetic unicellular parasite that alternates between a blood-sucking insect and a mammalian, host causing Chagas disease or American trypanosomiasis. In the insect gut, the parasite differentiates from the non-replicative trypomastigote forms that arrive upon blood ingestion to the non-infective replicative epimastigote forms. Epimastigotes develop into infective non-replicative metacyclic trypomastigotes in the rectum and are delivered via the feces. In addition to these parasite stages, transitional forms have been reported. The insect-feeding behavior, characterized by few meals of large blood amounts followed by long periods of starvation, impacts the parasite population density and differentiation, increasing the transitional forms while diminishing both epimastigotes and metacyclic trypomastigotes. To understand the molecular changes caused by nutritional restrictions in the insect host, mid-exponentially growing axenic epimastigotes were cultured for more than 30 days without nutrient supplementation (prolonged starvation). We found that the parasite population in the stationary phase maintains a long period characterized by a total RNA content three times smaller than that of exponentially growing epimastigotes and a distinctive transcriptomic profile. Among the transcriptomic changes induced by nutrient restriction, we found differentially expressed genes related to managing protein quality or content, the reported switch from glucose to amino acid consumption, redox challenge, and surface proteins. The contractile vacuole and reservosomes appeared as cellular components enriched when ontology term overrepresentation analysis was carried out, highlighting the roles of these organelles in starving conditions possibly related to their functions in regulating cell volume and osmoregulation as well as metabolic homeostasis. Consistent with the quiescent status derived from nutrient restriction, genes related to DNA metabolism are regulated during the stationary phase. In addition, we observed differentially expressed genes related to the unique parasite mitochondria. Finally, our study identifies gene expression changes that characterize transitional parasite forms enriched by nutrient restriction. The analysis of the here-disclosed regulated genes and metabolic pathways aims to contribute to the understanding of the molecular changes that this unicellular parasite undergoes in the insect vector.
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Adaptación Fisiológica , Enfermedad de Chagas , Insectos , Estadios del Ciclo de Vida , Inanición , Trypanosoma cruzi , Animales , Diferenciación Celular , Enfermedad de Chagas/genética , Enfermedad de Chagas/metabolismo , Enfermedad de Chagas/parasitología , Insectos/metabolismo , Insectos/parasitología , Insectos/fisiología , Mamíferos/parasitología , Transcriptoma/genética , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Trypanosoma cruzi/metabolismo , Trypanosoma cruzi/fisiología , Inanición/genética , Inanición/parasitología , Inanición/fisiopatología , Adaptación Fisiológica/genética , Adaptación Fisiológica/fisiología , Estadios del Ciclo de Vida/genética , Estadios del Ciclo de Vida/fisiologíaRESUMEN
Abstract Chagas disease is a neglected parasitic disease caused by Trypanosoma cruzi, whose treatment has remained unsatisfactory for over 50 years, given that it is limited to two drugs. Benznidazole (BZN) is an efficient antichagasic drug used as the first choice, although its poor water-solubility, irregular oral absorption, low efficacy in the chronic phase, and various associated adverse effects are limiting factors for treatment. Incorporating drugs with such characteristics into nanostructured lipid carriers (NLC) is a promising alternative to overcome these limiting obstacles, enhancing drug efficacy and bioavailability while reducing toxicity. Therefore, this study proposed NLC-BZN formulations in different compositions prepared by hot-melt homogenization followed by ultrasound, and the optimized formulation was characterized by FTIR, DRX, DSC, and thermogravimetry. Biological activities included in vitro membrane toxicity (red blood cells), fibroblast cell cytotoxicity, and trypanocidal activity against epimastigotes of the Colombian strain of T. cruzi. The optimized NLC-BZN had a small size (110 nm), negative zeta potential (-18.0 mV), and high encapsulation (1.64% of drug loading), as shown by infrared spectroscopy, X-ray diffraction, and thermal analysis. The NLC-BZN also promoted lower in vitro membrane toxicity (<3% hemolysis), and 50% cytotoxic concentration (CC50) for NLC-BZN in L929 fibroblast cells (110.7 µg/mL) was twice the value as the free BZN (51.3 µg/mL). Our findings showed that the NLC-BZN had higher trypanocidal activity than free BZN against the epimastigotes of the resistant Colombian strain, and this novel NLC-BZN formulation proved to be a promising tool in treating Chagas disease and considered suitable for oral and parenteral administration
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Trypanosoma cruzi/aislamiento & purificación , Difracción de Rayos X/instrumentación , Enfermedad de Chagas/patología , Enfermedades Desatendidas/clasificación , Enfermedades Parasitarias/patología , Análisis Espectral/instrumentación , Esguinces y Distensiones/clasificación , Termogravimetría/métodos , Técnicas In Vitro/métodos , Preparaciones Farmacéuticas/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodosRESUMEN
BACKGROUND: Strongyloidiasis and Chagas disease are endemic in northern Argentina. In this study we evaluate the association between S. stercoralis and T. cruzi infections in villages with diverse prevalence levels for these parasites. Further understanding in the relationship between these Neglected Tropical Diseases of South America is relevant for the design of integrated control measures as well as exploring potential biologic interactions. METHODOLOGY: Community based cross-sectional studies were carried in different villages of the Chaco and Yungas regions in Argentina. Individuals were diagnosed by serology for S. stercoralis and T. cruzi. The association between S. stercoralis and T. cruzi, and between anemia and the two parasites was evaluated using two approaches: marginal (Ma) and multilevel regression (Mu). RESULTS: A total of 706 individuals from six villages of northern Argentina were included. A total of 37% were positive for S. stercoralis, 14% were positive for T. cruzi and 5% were positive for both. No association was found between infection with S. stercoralis and T. cruzi in any of the models, but we found a negative correlation between the prevalence of these species in the different villages (r = -0.91). Adults (> 15 years) presented association with S. stercoralis (Ma OR = 2.72; Mu OR = 2.84) and T. cruzi (Ma OR = 5.12; Mu OR = 5.48). Also, 12% and 2% of the variance of infection with S. stercoralis and T. cruzi, respectively, could be explained by differences among villages. On the other hand, anemia was associated with infection with S. stercoralis (Ma OR = 1.73; Mu OR = 1.78) and was more prevalent in adults (Ma OR = 2.59; Mu OR = 2.69). CONCLUSION: We found that coinfection between S. stercoralis and T. cruzi is not more frequent than chance in endemic areas. However, the high prevalence for both parasites, raises the need for an integrated strategy for the control of STH and Chagas disease.