Acute Chagas disease outbreaks in Colombia in 2019.

This study seeks to address the critical knowledge gap surrounding the acute phase of Chagas disease in Colombia, with a specific focus on cases reported in 2019. The acute phase of Chagas disease is a pivotal period for intervention, yet it remains poorly understood, particularly in regions where oral transmission is presumed to be a significant factor. By analyzing these recent cases, our research aims to provide a deeper understanding of the dynamics of Chagas disease during its acute phase in Colombia in 2019. This understanding is essential not only for improving disease management and treatment strategies but also for enhancing public health responses to this neglected tropical disease. In particular, our study highlights the importance of identifying and addressing the unique challenges posed by oral transmission routes, which have been increasingly recognized within Colombia's Chagas disease landscape.

Genomic Epidemiology of Severe Acute Respiratory Syndrome Coronavirus 2, Colombia.

Coronavirus disease (COVID-19) in Colombia was first diagnosed in a traveler arriving from Italy on February 26, 2020. However, limited data are available on the origins and number of introductions of COVID-19 into the country. We sequenced the causative agent of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), from 43 clinical samples we collected, along with another 79 genome sequences available from Colombia. We investigated the emergence and importation routes for SARS-CoV-2 into Colombia by using epidemiologic, historical air travel, and phylogenetic observations. Our study provides evidence of multiple introductions, mostly from Europe, and documents >12 lineages. Phylogenetic findings validate the lineage diversity, support multiple importation events, and demonstrate the evolutionary relationship of epidemiologically linked transmission chains. Our results reconstruct the early evolutionary history of SARS-CoV-2 in Colombia and highlight the advantages of genome sequencing to complement COVID-19 outbreak investigations.

First Colombian consensus on congenital Chagas and clinical approach for women of child-bearing age diagnosed with Chagas / Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas

Congenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. To generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: «Chagas disease/congenital¼, «prevention and control¼, «diagnosis¼, «therapeutics¼ and «pregnancy¼. Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-to-face discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia.

La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas con- génito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos Mes (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizo, clasifico y organizo en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.

Detection of Trypanosoma cruzi antibodies in multitransfused patients in Colombia.

INTRODUCTION: Chagas disease is a public health problem in Latin America. Even though vector-borne infection is the most important transmission mode for this disease, other modes such as transfusions require evaluation. OBJECTIVE: To describe the prevalence of T. cruzi infection in multitransfused patients. MATERIALS AND METHODS: We detected IgG antibodies against T. cruzi by two immunoassays in samples from multitransfused patients in four hospitals located in Bogotá and Medellín, Colombia. We analyzed the association with known risk factors, and we calculated the odds ratios (OR) with 95% confidence intervals using Stata 11™ statistical software. RESULTS: In total, 479 samples were tested. Overall, T. cruzi antibody prevalence was 1.88% (nine patients). Five were onco-hematological patients, two were hemodialyzed, one had thalassemia, and one had suffered acute blood loss. We found no hemophilia patients. There was no association between known risk factors for transfusion-transmitted infection (such as the number of transfusion events, number of blood units and type of blood component) and the presence of anti-T. cruzi antibodies in this study. Only the hepatitis C virus infection showed a positive association with the presence of anti-T. cruzi antibodies (OR=5.68, 95% CI: 1.36-23.63). CONCLUSIONS: The results of this study showed a low frequency of T. cruzi infection in multitransfused patients, suggesting that the risk of transfusion infection in Colombia is low. Known risk factors for transfusion-related infection were not associated with the presence of anti-T. cruzi antibodies.

Detección de anticuerpos contra Trypanosoma cruzi en pacientes multitransfundidos, Colombia / Detection of Trypanosoma cruzi antibodies in multitransfused patients in Colombia

Resumen Introducción. La enfermedad de Chagas es un problema de salud pública en Latinoamérica y, aunque la transmisión vectorial es la más importante, deben evaluarse otras formas de transmisión, como la de las transfusiones. Objetivo. Describir la prevalencia de infección con Trypanosoma cruzi en pacientes sometidos a múltiples transfusiones o multitransfundidos. Materiales y métodos. Se detectaron anticuerpos IgG contra T. cruzi mediante dos inmunoensayos en muestras tomadas de pacientes sometidos a múltiples transfusiones en cuatro hospitales de Bogotá y Medellín, Colombia. Se analizó la asociación de factores de riesgo conocidos y se calcularon las razones de momios (odds ratio, OR) con un intervalo de confianza de 95 % (IC) utilizando el programa Stata 11(tm). Resultados. Se evaluaron 479 muestras. La prevalencia de anticuerpos contra T. cruzifue de 1,88 % (nueve pacientes): cinco pacientes remitidos de oncohematología, dos de hemodiálisis, uno tenía talasemia y uno había sufrido pérdida súbita y abundante de sangre. No se halló ningún paciente con hemofilia que resultara positivo, ni relación de los factores de riesgo de infección asociados con la transfusión de componentes sanguíneos, como el número de transfusiones, la cantidad de unidades de sangre y el tipo de componente, con la presencia de anticuerpos anti-T. cruzi. Solo se encontró relación entre la infección con el virus de la hepatitis C y la presencia de anticuerpos anti-T. cruzi (OR=5,68; IC95% 1,36-23,63). Conclusión. La frecuencia de infección por T. cruzi hallada en este grupo de pacientes sugiere que el riesgo de infección por transfusiones en Colombia es bajo. No se encontró relación entre los factores de riesgo asociados con la transfusión y la presencia de anticuerpos anti-T. cruzi.

Abstract Introduction: Chagas disease is a public health problem in Latin America. Even though vector-borne infection is the most important transmission mode for this disease, other modes such as transfusions require evaluation. Objective: To describe the prevalence of T. cruzi infection in multitransfused patients. Materials and methods: We detected IgG antibodies against T. cruzi by two immunoassays in samples from multitransfused patients in four hospitals located in Bogotá and Medellín, Colombia. We analyzed the association with known risk factors, and we calculated the odds ratios (OR) with 95% confidence intervals using Stata 11(tm) statistical software. Results: In total, 479 samples were tested. Overall, T. cruzi antibody prevalence was 1.88% (nine patients). Five were onco-hematological patients, two were hemodialyzed, one had thalassemia, and one had suffered acute blood loss. We found no hemophilia patients. There was no association between known risk factors for transfusion-transmitted infection (such as the number of transfusion events, number of blood units and type of blood component) and the presence of anti-T. cruzi antibodies in this study. Only the hepatitis C virus infection showed a positive association with the presence of anti-T. cruzi antibodies (OR=5.68, 95% CI: 1.36-23.63). Conclusions: The results of this study showed a low frequency of T. cruzi infection in multitransfused patients, suggesting that the risk of transfusion infection in Colombia is low. Known risk factors for transfusion-related infection were not associated with the presence of anti-T. cruzi antibodies.

Risk factors associated with Chagas disease in pregnant women in Santander, a highly endemic Colombian area.

OBJECTIVE: To determine the prevalence and risk factors associated with Chagas disease in pregnant women in an endemic area of Santander, Colombia. METHODS: Cross-sectional study included 23 municipalities of Santander, Colombia. Serological IFAT and ELISA tests were undertaken to detect IgG anti- Trypanosoma cruzi. A questionnaire was conducted for assessing the risk factors of each participant. Newborns were evaluated at birth and followed up to 1 year of age to determine congenital infection. RESULTS: An overall prevalence of 3.2% (95% CI 2.4-4.2) among 1518 pregnant women was detected. Prevalences by provinces were as follows: Guanentina: 6.0% (95% CI 4.1-8.5), García Rovira: 2.9% (95% CI: 1.5-4.8) and Comunera: 0.4% (0.4-2.3). The main risk factors identified were age >32 years old (OR: 2.1; 95% CI: 1.1-3.9); currently having a thatched roof (OR: 11.8; CI95% 2.2-63.2) and a thatched roof during childhood (OR: 3.0; 95% CI: 1.4-6.6); having below primary school education level (OR: 4.6; 95% CI: 2.2-9.5); and a history of a close contact with the vector (triatomine bugs) at least once during their lifetime (OR: 6.9; 95% CI: 3.7-12.9). No congenital cases were detected by parasitological or serological techniques. CONCLUSIONS: Prevalence of Chagas disease in pregnant women is a potential source of infection in this Colombian endemic area. The main risk factors associated with seropositivity were related to conditions favouring the contact with the vector. The results show that it is necessary to continue an active surveillance in order to offer diagnosis and treatment to mothers and their newborns in addition to screening to pregnant women from endemic areas.

Serological response to Helicobacter pylori infection among Latin American populations with contrasting risks of gastric cancer.

Gastric cancer is a rare outcome of chronic Helicobacter pylori infection. Serologic profiles may reveal bacterial, environmental and/or host factors associated with cancer risk. We therefore compared specific anti-H. pylori antibodies among populations with at least twofold differences in gastric cancer mortality from Mexico, Colombia and Chile. Our study included 1,776 adults (mean age 42 years) from three nationally representative surveys, equally divided between residents of high- and low-risk areas. Antibodies to 15 immunogenic H. pylori antigens were measured by fluorescent bead-based multiplex assays; results were summarized to identify overall H. pylori seropositivity. We used logistic regression to model associations between antibody seroreactivity and regional cancer risk (high vs. low), adjusting for country, age and sex. Both risk areas had similar H. pylori seroprevalence. Residents in high- and low-risk areas were seroreactive to a similar number of antigens (means 8.2 vs. 7.9, respectively; adjusted odds ratio, OR: 1.02, p = 0.05). Seroreactivities to Catalase and the known virulence proteins CagA and VacA were each significantly (p < 0.05) associated with residence in high-risk areas, but ORs were moderate (1.26, 1.42 and 1.41, respectively) and their discriminatory power was low (area under the curve < 0.6). The association of Catalase was independent from effects of either CagA or VacA. Sensitivity analyses for antibody associations restricted to H. pylori-seropositive individuals generally replicated significant associations. Our findings suggest that humoral responses to H. pylori are insufficient to distinguish high and low gastric cancer risk in Latin America. Factors determining population variation of gastric cancer burden remain to be identified.

Follow-up of an asymptomatic Chagas disease population of children after treatment with nifurtimox (Lampit) in a sylvatic endemic transmission area of Colombia.

BACKGROUND: Chagas disease is an anthropozoonosis caused by Trypanosoma cruzi. Two drugs are currently used for the etiological treatment of the disease: Nifurtimox (Lampit) and Benznidazole. This study presents a quasi-experimental trial (non-control group) of sixty-two patients who were treated for Chagas disease with Nifurtimox (Lampit), and were then followed for 30 months post-treatment. The safety of Nifurtimox (Lampit) for Chagas disease in this group of children primarily between 4 and 19 years old was also evaluated. MATERIALS AND METHODS: The 62 patients included in the study were selected when resulted seropositive for two out of three fundamentally different serological tests. All children were treated during two months according to protocols established by WHO. Monitoring was performed every twenty days to evaluate treatment safety. In 43 patients, two different serological tests: ELISA and IFAT; and two parasitological tests: blood culture, and real time PCR, (qPCR) were performed to assess therapeutic response, defined as post-treatment serological negativization. PRINCIPAL FINDINGS: All patients completed the treatment successfully, and six patients abandoned the post-treatment follow-up. Adverse effects occurred in 74% of patients, but only 4.8% of cases required temporary suspension to achieve 100% adherence to the 60-day treatment, and all symptoms reverted after treatment completion. Both parasite load (measured through qPCR) and antibodies (ELISA absorbance) evidenced a significant median reduction 6 months after treatment from 6.2 to 0.2 parasite equivalents/mL, and from 0.6 to 0.2 absorbance units respectively (p<0.001). Serological negativization by ELISA was evident since 6 months post-treatment, whereas by IFAT only after 18 months. Serological negativization by the two tests (ELISA and IFAT) was 41.9% (95%CI: 26.5-57.3) after 30 months post-treatment. qPCR was positive in 88.3% of patients pre-treatment and only in 12.1% of patients after 30 months. Survival analysis indicated that only 26.3% (95%CI: 15.5-44.8) persisted with negative qPCR during the whole follow-up period. CONCLUSIONS: Nifurtimox was very well tolerated and successfully reduced parasite load and antibody titers. Re-infection, lysed parasites or a lack of anti-parasitic activity could explain these persistently positive qPCR cases.

[Reproducibility of serological tests for the diagnosis of Trypanosoma cruzi infection in pregnant women in an endemic area of Santander, Colombia]. / Reproducibilidad de pruebas serológicas para el diagnóstico de infección por Trypanosoma cruzi en mujeres embarazadas de una zona endémica de Santander, Colombia.

INTRODUCTION: The diagnosis of chronic Trypanosoma cruzi infection is supported by serological tests whose reproducibility has not been well documented. OBJECTIVE: To evaluate the reproducibility of the serological tests ELISA, IFAT and IHAT for the diagnosis of T. cruzi infection in pregnant women in an endemic zone in Santander. MATERIALS AND METHODS: Through an evaluation study of diagnostic technologies, the reproducibility of the serological tests ELISA, IFAT and IHAT was determined in serum and eluted blood from pregnant women living in an endemic area for Chagas' disease in Santander. The samples were selected by cross sectional sampling. The software Stata ™ version 10.0 was used for statistical analysis. By means of the comparison of the highest kappa coefficient of each technique, the test with the best reproducibility was determined. RESULTS: A total of 777 samples were tested. In serum, ELISA (cutoff point: 0.3), IFAT (cutoff point: 1/32) and IHAT (cutoff point: 1/16) had kappa coefficients greater than 0.8 (0.98, 95% CI: 0.93-1.00; 0.98, 95% CI: 0.92-1.00 and 0.88, 95% CI: 0.74-0.97, respectively); no statistically significant differences among the three tests were found (p> 0.05). For the blood eluates, kappa coefficients were below 0.8 (highest kappa: 0.55, 95% CI: 0.41-0.68). CONCLUSIONS: For the three serological tests using serum, the reproducibility determined by the kappa coefficient was perfect. Selecting any of them is useful for the diagnosis of T. cruzi infection. Given its simplicity and cost, the ELISA test is recommended for screening for this infection.

[Preliminary evaluation of the commercial kit Chagas ( Trypanosoma cruzi ) IgG-ELISA ® in Colombian individuals]. / Evaluación preliminar de la prueba comercial Chagas ( Trypanosoma cruzi ) IgG-ELISA ® en individuos colombianos.

INTRODUCTION: The diagnosis of Chagas' disease is essential to provide early treatment and improve patients' prognosis . The discriminatory efficiency of the serological tests varies according to the disease prevalence and the test- antigen used . OBJECTIVE: To evaluate the discriminatory efficiency of the commercial kit Chagas ( Trypanosoma cruzi ) IgG-ELISA ® (Nova Tec Immunodiagnostica GmbBH) in a group of Colombian individuals, using indirect immunofluorescence antibody testing (IFAT) and enzyme immunoassay (ELISA) tests as references. MATERIALS AND METHODS: Seventy-eight samples from chronic chagasic patients (36 asymptomatic and 42 symptomatic) and 21 healthy controls were included. Seventeen samples from non-infected people with Chagas' disease epidemiological risk, seven with leishmaniasis and nine with non-chagasic cardiomyopathy were also analyzed. Real time PCR was performed on four individuals whose results differed among tests. RESULTS: Significant differences at 450 nm optical absorbance were found (p<0.0001) when the median absorbance values of healthy controls (0.143), asymptomatic (2.401) and symptomatic (2.776) chagasic patients were compared, as well as when asymptomatic and symptomatic patients (p=0.0408) and seronegative people with epidemiological risk (0.232), cardiomyopathy (0.367) or leishmaniasis (0.337) were compared with chagasic patients (p<0.0001). Finally, there were differences among healthy controls and non-infected people with epidemiological risk (p=0.0264), patients with non-chagasic cardiomyopathy (p=0.0015) and patients with leishmaniasis (p=0.002). Real-time PCR was positive in three out of four analyzed cases. CONCLUSIONS: The commercial ELISA test allowed us to discriminate the chagasic patients from the controls. A phase II study of diagnostic tests for determining field reliability of this test is required.

Reproducibilidad de pruebas serológicas para el diagnóstico de infección por Trypanosoma cruzi en mujeres embarazadas de una zona endémica de Santander, Colombia / Reproducibility of serological tests for the diagnosis of Trypanosoma cruzi infection in pregnant women in an endemic area of Santander, Colombia

Introducción. El diagnóstico de infección por Trypanosoma cruzi en fase crónica se hace por medio de pruebas serológicas cuya reproducibilidad no está muy documentada. Objetivo. Evaluar la reproducibilidad de las pruebas serológicas ELISA, IFI y HAI para el diagnóstico de infección por T. cruzi en mujeres embarazadas de una zona endémica de Santander. Materiales y métodos. Mediante la evaluación de la tecnología diagnóstica se determinó la reproducibilidad de las pruebas serológicas ELISA, IFI y HAI en muestras de suero y elución sanguínea, seleccionadas mediante muestreo de corte transversal y pertenecientes a mujeres embarazadas de una zona endémica para enfermedad de Chagas en Santander. Se usó el software Stata, versión 10.0, para los análisis estadísticos. La prueba con la mejor reproducibilidad se determinó por medio de la comparación de los índices kappa más altos de cada técnica. Resultados. Se evaluaron 777 sueros y elución sanguíneas. En suero, la prueba ELISA (punto de corte=0,3), la IFI (punto de corte=1/32) y la HAI (punto de corte=1/16) presentaron índices kappa mayores de 0,8 (0,98, IC 95% : 0,93-1,00; 0,98, IC 95% : 0,92-1,00 y 0,88, IC 95% : 0,74-0,97, respectivamente); no se observaron diferencias estadísticamente significativas entre las tres pruebas evaluadas (p>0,05). Para la elución sanguínea, el índice kappa estuvo por debajo de 0,8 (valor kappa más alto: 0,55, IC 95% : 0,41-0,68). Conclusiones. Las tres pruebas serológicas presentaron reproducibilidad perfecta en suero, determinada mediante el índice kappa, por lo que cualquiera de ellas sería útil para establecer el diagnóstico de infección por T. cruzi . Por su simplicidad y su costo, la prueba ELISA se recomienda como prueba de elección para los programas de tamización de esta infección.

Introduction: The diagnosis of chronic Trypanosoma cruzi infection is supported by serological tests whose reproducibility has not been well documented. Objective: To evaluate the reproducibility of the serological tests ELISA, IFAT and IHAT for the diagnosis of T. cruzi infection in pregnant women in an endemic zone in Santander. Materials and methods: Through an evaluation study of diagnostic technologies, the reproducibility of the serological tests ELISA, IFAT and IHAT was determined in serum and eluted blood from pregnant women living in an endemic area for Chagas´ disease in Santander. The samples were selected by cross sectional sampling. The software Stata ™ version 10.0 was used for statistical analysis. By means of the comparison of the highest kappa coefficient of each technique, the test with the best reproducibility was determined. Results: A total of 777 samples were tested. In serum, ELISA (cutoff point: 0.3), IFAT (cutoff point: 1/32) and IHAT (cutoff point: 1/16) had kappa coefficients greater than 0.8 (0.98, 95% CI: 0.93-1.00; 0.98, 95% CI: 0.92-1.00 and 0.88, 95% CI: 0.74-0.97, respectively); no statistically significant differences among the three tests were found (p> 0.05). For the blood eluates, kappa coefficients were below 0.8 (highest kappa: 0.55, 95% CI: 0.41-0.68). Conclusions: For the three serological tests using serum, the reproducibility determined by the kappa coefficient was perfect. Selecting any of them is useful for the diagnosis of T. cruzi infection. Given its simplicity and cost, the ELISA test is recommended for screening for this infection.

Evaluación preliminar de la prueba comercial Chagas ( Trypanosoma cruzi ) IgG-ELISA ® en individuos colombianos / Preliminary evaluation of the commercial kit Chagas ( Trypanosoma cruzi ) IgG-ELISA ® in Colombian individuals

Introducción. El diagnóstico de la enfermedad de Chagas es fundamental para brindar un tratamiento oportuno y mejorar el pronóstico del paciente. La capacidad discriminatoria de las pruebas serológicas para el diagnóstico varía de acuerdo con la prevalencia de la enfermedad y el antígeno utilizado en la prueba. Objetivo. Evaluar la capacidad discriminatoria de la prueba comercial Chagas ( Trypanosoma cruzi ) IgG-ELISA ® (NovaTec Immunodiagnostica GmbH) en un grupo de individuos colombianos utilizando la prueba de inmunofluorescencia indirecta (IFI) y el ensayo de inmunoabsorción enzimática (ELISA) como referencia. Materiales y métodos. Se incluyeron 78 muestras de pacientes crónicos (36 asintomáticos y 42 sintomáticos) y 21 de controles sanos. También se analizaron 17 individuos no infectados con riesgo epidemiológico para la enfermedad de Chagas, siete con leishmaniasis y nueve con enfermedad cardiaca. Se evaluaron por PCR en tiempo real cuatro individuos cuyos resultados variaron entre pruebas. Resultados. Se encontraron diferencias significativas a una densidad óptica de 450 nm (p<0,0001) al comparar la mediana de la absorbancia entre los controles sanos (0,143) y los asintomáticos (2,401) o sintomáticos (2,776), entre los asintomáticos y sintomáticos (p=0,0408), entre los seronegativos con riesgo (0,232), individuos con enfermedades cardiacas (0,367) o con leishmaniasis (0,337) y los pacientes con enfermedad de Chagas (p<0,0001), y entre los controles sanos y los pacientes seronegativos con riesgo (p=0,0264), con enfermedades cardiacas (p=0,0015) o con leishmaniasis (p=0,002). La PCR en tiempo real fue positiva en tres de los cuatro casos. Conclusiones. Esta prueba comercial de ELISA permitió discriminar a los pacientes con Chagas de los controles. Se requieren estudios de fase II para determinar las características operativas de la prueba.

Introduction: The diagnosis of Chagas´ disease is essential to provide early treatment and improve patients´ prognosis . The discriminatory efficiency of the serological tests varies according to the disease prevalence and the test- antigen used . Objective: To evaluate the discriminatory efficiency of the commercial kit Chagas ( Trypanosoma cruzi ) IgG-ELISA ® (Nova Tec Immunodiagnostica GmbBH) in a group of Colombian individuals, using indirect immunofluorescence antibody testing (IFAT) and enzyme immunoassay (ELISA) tests as references. Materials and methods: Seventy-eight samples from chronic chagasic patients (36 asymptomatic and 42 symptomatic) and 21 healthy controls were included. Seventeen samples from non-infected people with Chagas´ disease epidemiological risk, seven with leishmaniasis and nine with non-chagasic cardiomyopathy were also analyzed. Real time PCR was performed on four individuals whose results differed among tests. Results: Significant differences at 450 nm optical absorbance were found (p<0.0001) when the median absorbance values of healthy controls (0.143), asymptomatic (2.401) and symptomatic (2.776) chagasic patients were compared, as well as when asymptomatic and symptomatic patients (p=0.0408) and seronegative people with epidemiological risk (0.232), cardiomyopathy (0.367) or leishmaniasis (0.337) were compared with chagasic patients (p<0.0001). Finally, there were differences among healthy controls and non-infected people with epidemiological risk (p=0.0264), patients with non-chagasic cardiomyopathy (p=0.0015) and patients with leishmaniasis (p=0.002). Real-time PCR was positive in three out of four analyzed cases. Conclusions: The commercial ELISA test allowed us to discriminate the chagasic patients from the controls. A phase II study of diagnostic tests for determining field reliability of this test is required.

Primer consenso colombiano sobre Chagas congénito y orientación clínica a mujeres en edad fértil con diagnóstico de Chagas / First Colombian consensus on congenital Chagas and clinical approach to women of fertile age diagnosed with Chagas

La transmisión congénita de la enfermedad de Chagas ha sido poco estudiada en Colombia y existen pocos procedimientos rutinarios en el sistema de salud para el manejo de esta enfermedad. Por ello se desarrolló un consenso de expertos dirigido a generar recomendaciones de diagnóstico y tratamiento de Chagas congénito y orientación a mujeres en edad fértil. Con ese propósito se realizó una búsqueda extensiva de la literatura, empleando una combinación de términos MeSH (Chagas, Chagas congénito, prevención, control, diagnóstico, tratamiento y embarazo) para reflejar el estado del arte en cada tema de interés. Después de ello, se leyeron los resúmenes y aquellos seleccionados para análisis del texto completo. La literatura relevante se sintetizó, clasificó y organizó en tablas y se presentó al panel de expertos, el cual estaba constituido por 30 profesionales en diferentes áreas. Mediante la metodología Delphi se realizaron 2 rondas de cuestionarios virtuales y una reunión presencial en los cuales se evaluaron los niveles de acuerdo entre los participantes. Los puntos con falta de consenso durante las 2 rondas virtuales se expusieron durante las mesas de discusión en la ronda presencial. La evidencia utilizada se adaptó a las particularidades nacionales según el caso y se aprobó el contenido del documento final. Se propone que estas recomendaciones sean usadas por profesionales de la salud en Colombia.

Congenital transmission of Chagas disease has not been extensively studied in Colombia, and there are no standardized processes in the health system regarding the specific diagnosis, treatment and follow-up of this disease. In order to generate recommendations on congenital Chagas disease and Chagas in women of childbearing age in Colombia, a consensus of experts was developed. An extensive literature search through the Medline database was carried out using the MeSH terms: " Chagas disease/congenital " , " prevention and control " , " diagnosis " , " therapeutics " and " pregnancy " . Appropriate abstracts were selected and the full texts were analyzed. The relevant information was synthesized, classified, and organized into tables and figures and was presented to a panel of experts, which was composed of 30 professionals from various fields. Based on the Delphi methodology, three rounds of consultation were conducted. The first and second rounds were based on electronic questionnaires that measured the level of consensus of each question among the participants. The third round was based on a face-toface discussion focusing on those questions without consensus in the previous consultations. The evidence was adapted to national circumstances on a case-by-case basis, and the content the final document was approved. These recommendations are proposed for use in routine medical practice by health professionals in Colombia.

Blastocystis subtypes detected in humans and animals from Colombia.

Blastocystis is a common enteric protist colonizing probably more than 1 billion people along with a large variety of non-human hosts. This protist has been linked to symptoms and diseases such as abdominal pain, constipation, diarrhea, flatulence and irritable bowel syndrome (IBS). Remarkable genetic diversity has been observed, leading to the subdivision of the genus into multiple subtypes (ST), some of which are exclusively found in non-human hosts. The aim of this study was to determine the distribution of Blastocystis STs in different Colombian hosts. We obtained fecal samples positive for Blastocystis by microscopy from 277 humans, 52 birds, and 117 mammals (25 cattle, 40 opossums, 40 dogs, 10 rats and 2 howler monkeys). The samples were submitted to DNA extraction, PCR and sequencing using primers targeting the small subunit rRNA gene, and ST identification was performed according to DNA barcoding. We observed the occurrence of ST1 (34%) and ST2 (23%) and lower proportions of STs 3 (11.4%), 4 (0.8%), 6 (19.8%) and 8 (10.5%). Domesticated mammals shared the same STs as those usually seen in humans (ST1, ST2, ST3), while birds and marsupials had STs, which are usually rare in humans (ST6, ST8). Further studies implementing high-resolution molecular markers are necessary to understand the phylodynamics of Blastocystis transmission and the role of this stramenopile in health and disease in Colombian populations, and to expand on the phylogeographic differences observed so far with a view to exploring and understanding host-parasite co-evolution.

Productivity in physical and chemical science predicts the future economic growth of developing countries better than other popular indices.

Scientific productivity of middle income countries correlates stronger with present and future wealth than indices reflecting its financial, social, economic or technological sophistication. We identify the contribution of the relative productivity of different scientific disciplines in predicting the future economic growth of a nation. Results show that rich and poor countries differ in the relative proportion of their scientific output in the different disciplines: countries with higher relative productivity in basic sciences such as physics and chemistry had the highest economic growth in the following five years compared to countries with a higher relative productivity in applied sciences such as medicine and pharmacy. Results suggest that the economies of middle income countries that focus their academic efforts in selected areas of applied knowledge grow slower than countries which invest in general basic sciences.

Molecular epidemiology of human oral Chagas disease outbreaks in Colombia.

BACKGROUND: Trypanosoma cruzi, the causative agent of Chagas disease, displays significant genetic variability revealed by six Discrete Typing Units (TcI-TcVI). In this pathology, oral transmission represents an emerging epidemiological scenario where different outbreaks associated to food/beverages consumption have been reported in Argentina, Bolivia, Brazil, Ecuador and Venezuela. In Colombia, six human oral outbreaks have been reported corroborating the importance of this transmission route. Molecular epidemiology of oral outbreaks is barely known observing the incrimination of TcI, TcII, TcIV and TcV genotypes. METHODOLOGY AND PRINCIPAL FINDINGS: High-throughput molecular characterization was conducted performing MLMT (Multilocus Microsatellite Typing) and mtMLST (mitochondrial Multilocus Sequence Typing) strategies on 50 clones from ten isolates. Results allowed observing the occurrence of TcI, TcIV and mixed infection of distinct TcI genotypes. Thus, a majority of specific mitochondrial haplotypes and allelic multilocus genotypes associated to the sylvatic cycle of transmission were detected in the dataset with the foreseen presence of mitochondrial haplotypes and allelic multilocus genotypes associated to the domestic cycle of transmission. CONCLUSIONS: These findings suggest the incrimination of sylvatic genotypes in the oral outbreaks occurred in Colombia. We observed patterns of super-infection and/or co-infection with a tailored association with the severe forms of myocarditis in the acute phase of the disease. The transmission dynamics of this infection route based on molecular epidemiology evidence was unraveled and the clinical and biological implications are discussed.

Prevalence and risk factors for Chagas disease in pregnant women in Casanare, Colombia.

Knowledge of the prevalence and risk factors associated with maternal infection is the first step to develop a surveillance system for congenital transmission of Chagas disease. We conducted a cross-sectional study in Casanare, a disease-endemic area in Colombia. A total of 982 patients were enrolled in the study. A global prevalence of Trypanosoma cruzi infection of 4.0% (95% confidence interval [CI] = 2.8-5.3%) was found. Multivariate analysis showed that the most important risk-associated factors were age > 29 years (adjusted odds ratio [aOR] = 3.4, 95% CI = 0.9-12.4), rural residency (aOR = 2.2, 95% CI = 1.0-4.6), low education level (aOR = 10.2, 95% CI = 1.6-82.7), and previous knowledge of the vector (aOR = 2.2, 95% CI = 1.0-4.9). Relatives and siblings of infected mothers showed a prevalence of 9.3%. These findings may help physicians to investigate congenital cases, screen Chagas disease in siblings and relatives, and provide early treatment to prevent the chronic complications of Chagas disease.

Cisticercosis en Boyacá, Colombia: estudio de seroprevalencia / Cisticercosis in Boyacá, Colombia: seroprevalence study

Introducción. La cisticercosis humana es una infección producida por la forma larval de la Taenia solium, quepresenta múltiples manifestaciones clínicas de acuerdo a los órganos y tejidos que afecte, la neurocisticercosis(NC) es la forma más grave. En Colombia se desconoce la prevalencia de la cisticercosis en la población general.Objetivo. Estimar la prevalencia de la cisticercosis en el departamento de Boyacá en población general, a travésde pruebas serológicas.Materiales y Métodos. La metodología utilizada, teniendo en cuenta que se trata de una encuesta departamentalcon proyección nacional, se basó en tres fases, una primera correspondiente a su diseño estadístico y planteamiento metodológico, una segunda etapa dada por la ejecución en campo para obtener información a través de instrumentosde recolección de datos, toma de muestras de sangre y procesamiento de las mismas en el Laboratorio de Parasitología del Instituto Nacional de Salud mediante la técnica de Elisa y una última fase de consolidación, análisisy divulgación de los resultados. El diseño muestral fue probabilístico, trietápico, de conglomerados y estratificado. Resultados. La prevalencia general de anticuerpos anti-cisticerco en el departamento de Boyacá fue de 4,02%.Entre hábitos de aseo no realizar el lavado de manos después de ir al sanitario configura un riesgo muy importante(RP=4,63 I.C 95% 4,50 – 4,76 p <0,05) junto con otros hábitos como la eliminación de excretas al aire libre o enletrina sin pozo (RP=1,27 I.C 1,24 – 1,31) p <0,05.Conclusiones. Se logró conocer la seroprevalencia de la cisticercosis determinada en población general deldepartamento de Boyacá y algunos factores epidemiológicos determinantes de esta patología, todo ello puedeestablecerse como una línea base para dar inicio al proceso de la vigilancia epidemiológica, control y prevenciónde esta patología.

Introduction. Human cysticercosis is an infection caused by the larval form of Taenia solium, which has many clinicalmanifestations according to the organs and tissues affected, being the neurocysticercosis (NC) the most severe form. In Colombia, the prevalence of cysticercosis is unknown in the general population and habits exist in our population. Objective. To estimate the prevalence of the cysticercosis in Boyaca Department in general population through serologicaltests. Materials and Methods. The methodology used, taking into account that this is a survey at the departmental level with national projection was based on three phases, an initial design for statistical and methodological approach, a second stage performance given by its field to obtain information through data collection instruments, blood sampling and processing them in the Laboratory of Parasitology, National Institute of Health by ELISA and a final phase of consolidation, analysis and dissemination of results. The sample design was probabilistic, three-stage, stratified cluster. Results. The overall prevalence of anti-cysticercus antibodies in the department of Boyacá was 4.02%. Hygiene habitswere a group of factors which are found not to hand washing after using the bathroom set up a very significant risk (RP = 4.63 CI 4.50 to 4.76) p <0.05 with other habits, such as excreta or in outdoor pit latrine without (RP = 1.27 CI 1.24 to 1.31) p <0.05. Conclusions. Understanding was reached on the status of cysticercosis seroprevalence determined by the general populationof the department of Boyacá and some determinants of this disease, constituting a baseline you can start the process of epidemiological surveillance, control and prevention of this disease in this department.

Caracterización molecular de los genes histona H2A y ARNsno-Cl de Trypanosoma rangeli: aplicación en pruebas diagnósticas / Molecular characterization of histone H2A and snoRNA-Cl genes of Trypanosoma rangeli: application in diagnostic tests

La aplicación de la reacción en cadena de la polimerasa (PCR) para detectar e identificar Trypanosoma rangeli y Trypanosoma rangeli presenta a menudo dificultades de interpretación. Así, algunas pruebas generan la amplificación de bandas similares provenientes de uno de los dos parásitos, fragmentos polimórficos de un mismo parásito, o la prevalencia en la detección de T. cruzi en infecciones mixtas. En este estudio se presentan y analizan los trabajos de investigación básica realizados con el objeto de diseñar y estandarizar pruebas de PCR específicas de cada parásito. Los iniciadores TcH2AF/R se diseñaron sobre la base de la región diferencial observada entre las unidades génicas que contienen los genes h2a en estos tripanosomas. Esta pareja de iniciadores amplifican un fragmento de 234 pb específico para T. cruzi (cepas I y II). Los iniciadores TrF/R2 anillan en las regiones intergénicas del fragmento génico de 801 pb codificante para seis transcritos que forman la agrupación ARNsno-Cl en T. rangeli. Estos iniciadores amplifican un fragmento de 620 pb exclusivo de las cepas KP1(-) y KP1(+) de este parásito. La aplicación de estas PCR en vectores infectados y en pacientes con enfermedad de Chagas muestra que ambas pruebas constituyen herramientas útiles para el diagnóstico y la identificación diferencial de estos tripanosomátidos.

The application of polymerase chain reaction (PCR) to detect Trypanosoma rangeli and Trypanosoma rangeli often presents interpretation challenges. For example, some tests yield the amplification of similar bands from either parasite, polymorphic fragments of the same parasite, or present deviation towards T. cruzi in mixed infections. In this study, the basic researching needed for designing and standardizating specific PCR tests for each parasite species PCR are shown and analyzed. The TcH2AF/R primers were designed on the basis of the differential gene region observed between the histone h2a genic units of these parasites. These primers amplify a specific 234 bp fragment in T. cruzi (T. cruzi I and II strains). The TrF/R2 primers anneal to the intergenic regions of an 801 bp gene fragment encoding for six transcripts that conform the snoRNA-Cl cluster in T. rangeli. These primers amplify a fragment of 620 bp exclusively in KP1(-) and KP1(+) strains of the parasite. The application of these PCR tests in infected vectors and in chagasic patients show that both tests constitute useful tools for the diagnosis and differential identification of these Trypanosomatids. Key words: histone, RNA small nucleolar (snoRNA), polymerase chain reaction (PCR), Trypanosoma.

Factores relacionados con enfermedades transmitidas por alimentos en restaurantes de cinco ciudades de Colombia, 2007 / Factors related to foodborne diseases in restaurants from 5 Colombian cities, 2007

Antecedentes. En Colombia existe subregistro de la notificación de casos de enfermedades transmitas por alimentos. La Organización Mundial de la Salud plantea que la mayoría de las contaminaciones de alimentos que generan enfermedades transmitidas por alimentos ocurren por problemas sanitarios y de manipulación, dentro del hogar y en sitios en donde se elaboran para la venta. Objetivo. Identificar los factores relacionados con la transmisión de enfermedades transmitidas por alimentos en expendios de alimentos. Materiales y métodos. En cinco ciudades de Colombia se encuestaron 300 establecimientos y 1.522 manipuladores de alimentos a quienes se les hizo control microbiológico de manos y, a 1.286, examen coprológico y coprocultivo. Resultados. Veinticinco establecimientos (8,3 por ciento) no tenían una ubicación adecuada, 113 (37,7 por ciento) no contaban con planes de saneamiento y sólo 26 (8,7 por ciento) realizaban prácticas apropiadas de almacenamiento. En los manipuladores se halló que 765 (50,3 por ciento) ingresaron con examen médico y 924 (60,7 por ciento) realizaron curso de manipulación de alimentos. En sus prácticas de trabajo se evidenció manejo simultáneo de dinero y alimentos (17 por ciento), uso de joyas (15,2 por ciento), uñas largas y con esmalte (8,9 por ciento), y 15,2 por ciento refirieron no lavarse las manos cuando manipulaban dinero y en los no capacitados se halló 1,3 veces más frecuente este hábito (RR=1,36 IC 95 por ciento=1,10 – 1,69). Se encontraron parásitos intestinales en 26,9 por ciento; 49 (3,8 por ciento) fueron positivos para parásitos patógenos, 6 (0,46 por ciento) para enterobacterias patógenas y 8 (0,52 por ciento) cultivos de manos, para Staphylococcus aureus.