Browsing by Autor "Faustino Torrico"

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A <i>Trypanosoma cruzi</i> Antigen and Epitope Atlas: deep characterization of antibody specificities in Chagas Disease patients across the Americas
(2022) Alejandro D. Ricci; Leonel Bracco; Janine M. Ramsey; Melissa S. Nolan; Mary K. Lynn; Jaime Altcheh; Griselda Ballering; Faustino Torrico; Norival Kesper; Juan Carlos Villar
ABSTRACT During an infection, the immune system produces pathogen-specific antibodies. With time, these antibody repertoires become specific to the history of infections and represent a rich source of diagnostic markers. However, the specificities of these antibodies are mostly unknown. Here, using high-density peptide arrays we examined the specificities of human antibody repertoires of Chagas disease patients. Chagas disease is a neglected disease caused by Trypanosoma cruzi, a protozoan parasite that evades immune mediated elimination and mounts long-lasting chronic infections. We describe here the first proteome-wide search for antigens and epitopes and their seroprevalence at the individual level and across human populations. In a first discovery screening of 2.84 million short peptides spanning two T. cruzi proteomes we found 3,868 distinct antigenic protein regions. Further analysis of repertoires from 71 individuals provided information on their seroprevalence and showed a large fraction of private epitopes of low seroprevalence (<20%), and novel high seroprevalence antigens. Using single-residue mutagenesis we found the core epitopes required for antibody binding for 232 of these epitopes. These datasets enable the study of the Chagas antibody repertoire at an unprecedented depth and granularity, while also providing a rich source of novel serological biomarkers. IMPACT STATEMENT This work reveals the diversity and extent of antibody specificities in Chagas Disease and provides a wealth of well-defined antigenic markers for diagnosis and development of serological applications for this neglected infectious disease.
A new patient registry for Chagas disease
(Public Library of Science, 2020) Peter J. Hotez; María Elena Bottazzi; Nathalie Strub‐Wourgaft; Sergio Sosa‐Estáni; Faustino Torrico; Leire Pajín; Marcelo Abril; Javier Sancho
There is urgency to establish a new and comprehensive patient registry for the millions of people who live in vulnerable social conditions with Chagas disease.
A Phase 2, Randomized, Multicenter, Placebo-Controlled, Proof-of-Concept Trial of Oral Fexinidazole in Adults With Chronic Indeterminate Chagas Disease
(Oxford University Press, 2022) Faustino Torrico; Joaquím Gascón; Lourdes Ortiz; Jimy Pinto; Gimena Rojas; Alejandro Palacios; Fabiana Barreira; Bethania Blum; Alejandro G. Schijman; Michel Vaillant
NCT02498782.
A tribute to Cecilio Romaña: Romaña’s sign in Chagas disease
(Public Library of Science, 2020) Nathan Beucler; Faustino Torrico; David Brynn Hibbert
Achievements and Challenges upon the Implementation of a Program for National Control of Congenital Chagas in Bolivia: Results 2004–2009
(Public Library of Science, 2013) Cristina Alonso‐Vega; Claire Billot; Faustino Torrico
Bolivia is one of the most endemic countries for Chagas disease. Data of 2005 shows that incidence is around 1.09‰ inhabitants and seroprevalence in children under 15 ranged from 10% in urban areas to 40% in rural areas. In this article, we report results obtained during the implementation of the congenital Chagas program, one of the biggest casuistry in congenital Chagas disease, led by National Program of Chagas and Belgian cooperation from 2004 to 2009. The program strategy was based on serological results during pregnancy and on the follow up of children born from positive mothers until one year old; if positive, treatment was done with Benznidazole, 10 mg/Kg/day/30 days with one post treatment control 6 months later. Throughout the length of the program, a total of 318,479 pregnant women were screened and 23.31% were detected positive. 42,538 children born from positive mothers were analyzed at birth by micromethod, of which 1.43% read positive. 10,120 children returned for their second micromethod control of which 2.29% read positive, 7,650 children returned for the serological control, of which 3.32% turned out positive. From the 1,093 positive children, 70% completed the 30 day-treatment and 122 returned for post treatment control with 96% showing a negative result. It has been seen that maternal-fetal transmission rates vary between 2% and 4%, with an average of 2.6% (about half of previously reported studies that reached 5%). In this work, we show that it is possible to implement, with limited resources, a National Congenital Chagas Program and to integrate it into the Bolivian health system. Keys of success are population awareness, health personnel motivation, and political commitment at all levels.
AMNIOTIC FLUID IS NOT USEFUL FOR DIAGNOSIS OF CONGENITAL TRYPANOSOMA CRUZI INFECTION
(American Society of Tropical Medicine and Hygiene, 2006) Myrna Virreira; Sabrina Sales Martínez; Cristina Alonso‐Vega; Faustino Torrico; Marco Solano; Mary Cruz Torrico; Rudy Parrado; Carine Truyens; Yves Carlier; Michal Svoboda
Although Trypanosoma cruzi can be transmitted transplacentally and induce congenital infection, no data are available about the presence of this parasite in human amniotic fluid. We examined 8, 19, and 4 amniotic fluid samples (collected at delivery or by aspiration of gastric content of neonates) from control uninfected mothers (M−B−), infected mothers delivering uninfected newborns (M+B−), and mothers of confirmed congenital cases (M+B+), respectively. Polymerase chain reaction (PCR), using nuclear and kinetoplastic DNA primers (Tcz1-Tcz2 and 121–122), were negative for all control M−B− samples, but positive for 5 of 19 M+B− and 2 of 4 M+B+ samples. To determine the number of parasites in the positive samples, real-time PCR using S35/S36 kinetoplastic DNA was performed. Only one M+B+ sample presented a high parasitic DNA amount, whereas the other six PCR-positive samples displayed traces of T. cruzi DNA. In conclusion, the release of parasites in amniotic fluid is probably a rare event that cannot be helpful for the routine diagnosis of congenital Chagas disease.
Are maternal re‐infections with <i>Trypanosoma cruzi</i> associated with higher morbidity and mortality of congenital Chagas disease?
(Wiley, 2006) Faustino Torrico; Cristina Alonso Vega; Eduardo Suárez; Tatiana Tellez; Laurent Brutus; Patricia Rodríguez; Mary‐Cruz Torrico; Dominique Schneider; Carine Truyens; Yves Carlier
Frequent bites of blood sucking Reduvidae during pregnancy do not induce maternal anaemia, but, likely through multiple maternal re-infections with T. cruzi, increase maternal parasitemia and worsen congenital Chagas disease. Maternal dwelling in areas of high VD is associated with a serious increased risk of severe and mortal congenital Chagas disease.
Benznidazole in Chagas disease study: do the data justify progression to phase 3? – Authors’ reply
(Elsevier BV, 2021) Faustino Torrico; Fabiana Barreira; Nathalie Strub‐Wourgaft; Isabella Ribeiro; Sergio Sosa‐Estáni
Big is not better: Comparing two alpha-Gal-bearing glycotopes in neoglycoproteins as biomarkers for Leishmania (Viannia) braziliensis infection
(Elsevier BV, 2023) Alba L. Montoya; Eileni R. Gil; Irodiel Vinales; Igor L. Estevao; Paola Taboada; Mary Cruz Torrico; Faustino Torrico; Jorge D. Marco; Igor C. Almeida; Katja Michael
Can wild foci in Bolivia jeopardize Chagas disease control efforts?
(Elsevier BV, 2005) François Noireau; Mirko Rojas Cortez; Fernando A. Monteiro; Ana María Jansen; Faustino Torrico
Caracterización de la infestación de viviendas por Aedes aegypti en el área metropolitana de Cochabamba, Bolivia: nuevos registros altitudinales
(2016) Evelin Aquino Rojas; Mirko Rojas Cortez; Jorge Espinoza; Efraín Vallejo; Daniel Lozano; Faustino Torrico
La rapida proliferacion del vector en areas de clima calido y baja altitud, como el oriente y la amazonia boliviana, genero la necesidad de analizar la adaptabilidad del A. aegypti en zonas templadas, tal es el caso de los valles mesotermicos de la ciudad metropolitana de Cochabamba. Objetivo : l a evaluacion entomologica se realizo en una muestra de 264 viviendas seleccionadas al azar en Abril del 2016. El area de estudio abarca zonas urbanas de seis municipios (Cercado, Sacaba, Colcapirhua, Tiquipaya, Quillacollo y Vinto) del departamento de Cochabamba. El diseno para el estudio fue epidemiologico, transversal de diagnostico comunitario . Metodos : de la muestra referida, 100 viviendas se encontraron larvas de A. aegypti , que corresponde a un 38% de infestacion larvaria y un Indice Breteau de 1,0. Las llantas, turriles y recipientes desechables son un factor de riesgo para la propagacion y adaptacion del vector en nuestra region. Resultados : los hallazgos confirman la dispersion del A. aegypti con algunas regiones con mayor prevalencia (zona sud de cercado urbano, Colcapirhua y Quillacollo en el valle bajo). Tambien se evidencio por primera vez que la dispersion y colonizacion de larvas de A. aegypti en el area de estudio alcanzo una altura minima de 2 538 m/s/n/m. y una altura maxima de 2 623 m.s.n.m. Conclusiones : La prevencion y el control de A. aegypti , en la metropoli de Cochabamba va a requerir un trabajo mancomunado integral e intersectorial enfocados en una estrategia de intervencion de gestion socioambiental de corresponsabilidad y participacion comunitaria, generando como resultado un Manejo Integrado del Vector. Palabras claves : Aedes aegypti , epidemiologia, infestacion, Bolivia .
Characterization of digestive disorders of patients with chronic Chagas disease in Cochabamba, Bolivia
(Elsevier BV, 2019) Jimy-Jose Pinto; María‐Jesús Pinazo; Jaime Saravia; Ingrid Gainsborg; Helmut-Ramon Magne; Míriam Cuatrecasas; Núria Cortes-Serra; Daniel-Franz Lozano; Joaquím Gascón; Faustino Torrico
Clinical and immunological characteristics of tegumentary leishmaniasis cases in Bolivia
(Public Library of Science, 2021) Cristina Ballart; Mary Cruz Torrico; Gisela Vidal; Faustino Torrico; Daniel Lozano; Montserrat Gállego; Lilian Pinto; Ernesto Rojas; Ruth Aguilar; Carlota Dobaño
In Bolivia, parasitological diagnosis remains the reference standard in diagnosis of leishmaniasis because of its high specificity, whereas the sensitivity varies over a wide range leading to loss of cases. Until more accurate tools are implemented, all patients should be tested by both smears and culture of lesion aspirates to minimize the risk of false negatives. Our results showed higher concentrations of several cytokines in MCL compared to CL, but no differences were observed between CL and no-cases. In addition, none of the cytokines differed between primary and secondary infections. These results highlight the need of further research to identify biomarkers of susceptibility and disease progression, in addition to looking at the local cellular immune responses in the lesions.
Co-infección por Trypanosoma Cruzi y VIH: reporte de un caso de meningoencefalitis chagásica en Cochabamba, Bolivia
(Universidad Internacional de La Rioja, 2013) Faustino Torrico; María del Rosario Castro Soto
The co-infection of Chagas disease with HIV can be a common in countries where both diseases are endemic, 70% of cases of chronic Chagas reactivated in HIV-infected patients with less than 200 CD4 / ul of blood giving more frequently CNS lesions with meningoencephalitis. The treatment of these cases of reactivation of infection by T. cruzi is an urgency to reduce the high risk of mortality due to the\nassociation of the two diseases. We report on a male patient, a case of reactivation of chronic Chagas infection, which is presented as a picture of meningoencephalitis and confirmed by demonstration of the parasite in CSF and peripheral blood, four months after specific treatment, we observed a relapse of the T. cruzi infection with a new picture of meningoencephalitis.
Co-Infection of Leishmania (Viannia) braziliensis and HIV: Report of a Case of Mucosal Leishmaniasis in Cochabamba, Bolivia
(American Society of Tropical Medicine and Hygiene, 2009) Faustino Torrico; Rudy Parrado; Rosario Castro; Carla Jimena Marquez; Mary Cruz Torrico; Marco Solano; Richard Reithinger; Ana Lineth García
We describe the first case of Leishmania/HIV co-infection reported in Bolivia. Initially hospitalized with a diagnosis of pneumonia and bronchitis, the patient had numerous cutaneous and mucosal lesions caused by Leishmania (Viannia) braziliensis. The patient was also diagnosed as severely immunocompromised because of HIV infection.
COMPARISON OF POLYMERASE CHAIN REACTION METHODS FOR RELIABLE AND EASY DETECTION OF CONGENITAL TRYPANOSOMA CRUZI INFECTION
(American Society of Tropical Medicine and Hygiene, 2003) Myrna Virreira; Faustino Torrico; Carine Truyens; Cristina Alonso‐Vega; Marco Solano; Yves Carlier; Michal Svoboda
The polymerase chain reaction (PCR) is a potentially interesting diagnostic tool for detecting congenital Trypanosoma cruzi infection at birth. We have compared the sensitivity and capacity of a group of T. cruzi PCR primers in detecting the complete spectrum of known T. cruzi lineages, and to improve and simplify the detection of infection in neonatal blood. We found that the two primers, Tcz1/Tcz2 and Diaz1/Diaz2, which target the 195-basepair satellite repeat, detected all parasitic lineages with the same sensitivity. However, the intensity of the amplicon was somewhat higher with Tcz1/Tcz2. For other tested primers (nuclear DNA primers BP1/BP2, O1/O2, Pon1/Pon2, and Tca1/Tca2 and kinetoplast DNA primers S35'/S36' and 121/122), either the intensity of amplicons varied according to T. cruzi lineages or the PCR assay was less sensitive. The use of the Tcz1/Tcz2 primers, which target a tandem repetitive sequence, requires a careful determination of the appropriate amount of Taq polymerase to avoid the formation of smears and multiple amplicon bands. The Tcz1/Tcz2 primers resulted in an intense 200-basepair amplicon with DNA extracted from blood equivalent to 0.02 parasites per assay when used with a simple DNA extraction method and of a low amount of Taq polymerase from a standard PCR kit. To better assess such PCR protocol, we assayed 311 samples of neonatal blood previously tested by parasitologic methods. The reliability of our PCR test was demonstrated, since all the 18 blood samples from newborns with congenital T. cruzi infection were positive, whereas the remaining samples (30 from control newborns of uninfected mothers and 262 of 263 from babies born to infected mothers) were negative. Since our PCR method is simple, reliable, robust, and inexpensive, it appears suitable for the detection of T. cruzi infection in neonatal blood, even in laboratories that are not equipped for performing the PCR.
Conducta sexual y reproductiva durante la adolescencia de los estudiantes de la Universidad Mayor de San Simón
(2019) Norah Velásquez Garcia; Gimena Rojas; Liz Guisela Rojas Delgadillo; Daniel Franz Lozano Beltrán; Faustino Torrico
Objetivos: analizar los factores relacionados con la conducta sexual de riesgo, durante la adolescencia de los estudiantes de la Universidad Mayor de San Simón, gestión 2018. Métodos: estudio retrospectivo, de cohorte, el muestreó fue no probabilístico con criterios de inclusión y exclusión. Se aplicó una encuesta auto administrada en cuatro sitios diferentes de la universidad. El análisis de los datos se realizó con el programa Epi-info v.7.2, empleando análisis uni y bivariado, como medidas de asociación OR, chi2 con un valor de p significante menor o igual a 0,05. Resultados: la proporción de participantes que iniciaron su vida sexual activa durante la adolescencia fue del 50%, de estos el 31% no utiliza ningún método anticonceptivo y el 69% si utiliza algún método de anticoncepción, de los cuales el 46% prefiere utilizar el preservativo masculino o la píldora del día siguiente. Se encontró una relación significativa del inicio de vida sexual precoz (antes de los 16 años) con las variables: ser varón, provenir de una familia disfuncional, poco acceso a fuentes de información sobre sexualidad, consumo de sustancias psicoactivas antes de la relación sexual y el haber tenido una pareja sexual informal o casual. Conclusión: una conducta sexual adecuada en el adolescente depende en gran medida de un entorno familiar funcional y del acceso adecuado a información sobre sexualidad y reproducción. La prevención de embarazos no deseados y de infecciones de transmisión sexual en adolescentes debe centrarse también en el entorno familiar y de la sociedad del adolescente.
CONGENITAL CHAGAS DISEASE IN BOLIVIA IS NOT ASSOCIATED WITH DNA POLYMORPHISM OF TRYPANOSOMA CRUZI
(American Society of Tropical Medicine and Hygiene, 2006) Myrna Virreira; Cristina Alonso‐Vega; Marco Solano; Juan Jijena; Laurent Brutus; Zulema Bustamante; Carine Truyens; Dominique Schneider; Faustino Torrico; Yves Carlier
This study aims to typify the Trypanosoma cruzi (sub)lineage(s) in umbilical cord blood of congenitally infected Bolivian newborns, using PCR amplifications of "Region Markers", mini-exon or kDNA fragments followed by hybridization or sequencing. New probes were also designed to distinguish three variants within the TcIId sublineage. The IIb, IId, or IIe T. cruzi sublineages, as well as different variants of the IId sublineage, were detected in infected neonates, whereas mixed infections were not found. The frequencies of the IId sublineage were similar in neonates (95.1%) and adults of the same area (94.1%). The IId-infected newborns displayed either asymptomatic, or severe and fatal clinical forms of congenital Chagas disease, as well as low or high parasitemia. Altogether these data show that T. cruzi DNA polymorphism, based on the presently available markers, is not associated with the occurrence of congenital infection or the development of severe clinical forms of congenital Chagas disease.
Congenital Chagas Disease: Recommendations for Diagnosis, Treatment and Control of Newborns, Siblings and Pregnant Women
(Public Library of Science, 2011) Yves Carlier; Faustino Torrico; Sergio Sosa‐Estáni; Graciela Russomando; Alejandro O. Luquetti; Héctor Freilij; Pedro Albajar-Viñas
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Congenital infection with Trypanosoma cruzi: from mechanisms of transmission to strategies for diagnosis and control
(Brazilian Society of Tropical Medicine, 2003) Yves Carlier; Faustino Torrico