Ten years follow-up of the largest oral Chagas disease outbreak: Cardiological prospective cohort study.

BACKGROUND: Chagas disease (ChD) is the most important endemy in Latin America. Some patients, develop chronic Chagasic cardiopathy (CCC) years after the acute phase. It is unknown if patients infected by the oral route have higher risk of developing early CCC. METHODS AND FINDINGS: A prospective cohort study was conducted to assess morbidity and mortality during 10 years observation in 106 people simultaneously infected and treated in the largest known orally transmitted ChD outbreak in 2007. A preschooler died during the acute phase, but thereafter was no mortality associated to ChD. All acute phase findings improved in the first-year post-treatment. Each person was evaluated 8.7 times clinically, 6.4 by electrocardiogram (ECG)/Holter, and 1.7 by echocardiogram. Based on prevalence, the number of people who had any abnormalities (excluding repolarization abnormalities and atrial tachycardia which decreased) was higher than 2007, since they were found at least once between 2008-2017. However, when we evaluated incidence, except for clinical bradycardia and dizziness, it was observed that the number of new cases of all clinical and ECG findings decreased at the end of the follow-up. Between 2008-2017 there was not incidence of low voltage complex, 2nd degree AV block, long QT interval, left bundle branch block or left ventricular dysfunction that allowed the diagnosis of CCC. Total improvement prevailed over the persistence of all clinical and ECG/Holter findings, except for sinus bradycardia. Incomplete right bundle branch block, sinus bradycardia and/or T-wave inversion were diagnosed persistently in 9 children. The second treatment did not have significant influence on the incidence of clinical or ECG/Holter findings. CONCLUSIONS: At the end of the 10-year follow-up, there were not clinical or ECG/Holter criteria for classifying patients with CCC. The incidence of arrhythmias and repolarization abnormalities decreased. However, special attention should be paid on findings that not revert as sinus bradycardia, or those diagnosed persistently in all ECG as sinus bradycardia, incomplete right bundle branch block or T-wave inversion. Early diagnosis and treatment may have contributed to the rapid improvement of these patients. In ChD follow-up studies prevalence overestimates the real dimension of abnormalities, the incidence looks as a better indicator.

Defects in immune response to Toxoplasma gondii are associated with enhanced HIV-1-related neurocognitive impairment in co-infected patients.

Human immunodeficiency virus-1 (HIV-1) and Toxoplasma gondii can invade the central nervous system and affect its functionality. Advanced HIV-1 infection has been associated with defects in immune response to T. gondii, leading to reactivation of latent infections and development of toxoplasmic encephalitis. This study evaluates relationship between changes in immune response to T. gondii and neurocognitive impairment in HIV-1/T. gondii co-infected patients, across different stages of HIV-1 infection. The study assessed the immune response to T. gondii by measuring cytokine production in response to parasite antigens, and also neurocognitive functions by performing auditory and visual P300 cognitive evoked potentials, short term memory (Sternberg) and executive function tasks (Wisconsin Card Sorting Test-WCST) in 4 groups of individuals: HIV-1/T. gondii co-infected (P2), HIV-1-infected/T. gondii-non-infected (P1), HIV-1-non-infected/T. gondii-infected (C2) and HIV-1-non-infected/T. gondii-non-infected (C1). Patients (P1 and P2) were grouped in early/asymptomatic (P1A and P2A) or late/symptomatic (P1B/C and P2B/C) according to peripheral blood CD4+ T lymphocyte counts (>350 or <350/µL, respectively). Groups were compared using T-student or U-Mann-Whitney tests as appropriate, p<0.05 was considered as significantly. For P300 waves, HIV-1-infected patients (P1) had significantly longer latencies and significantly smaller amplitudes than uninfected controls, but HIV-1/T. gondii co-infected patients (P2) had significantly longer latencies and smaller amplitude than P1. P1 patients had significantly poorer results than uninfected controls in Sternberg and WCST, but P2 had significantly worse results than P1. HIV-1 infection was associated with significantly lower production of IL-2, TNF-α and IFN-γ in response to T. gondii from early/asymptomatic stages, when comparing P2 patients to C2 controls. These findings may indicate impairment in anti-parasitic response in co-infected patients, facilitating early limited reactivation of the parasitic latent infection, therefore creating cumulative damage in the brain and affecting neurocognitive functions from asymptomatic stages of HIV-1 infection, as suggested by defects in co-infected patients in this study.

Genetic Characterization of Trypanosoma cruzi I Populations from an Oral Chagas Disease Outbreak in Venezuela: Natural Resistance to Nitroheterocyclic Drugs.

The oral transmission of Chagas disease (oCD) in Venezuela announced its appearance in 2007. Different from other populations affected by oCD and despite close supervision during treatment with nitroheterocyclic drugs, the result was treatment failure. We studied genetic features of natural bloodstream parasite populations and populations after treatment of nine patients of this outbreak. In total, we studied six hemoculture isolates, eight Pre-Tx blood samples, and 17 samples collected at two or three Post-Tx time-points between 2007 and 2015. Parasitic loads were determined by quantitative polymerase chain reaction (qPCR), and discrete typing units (DTU), minicircle signatures, and Tcntr-1 gene sequences were searched from blood samples and hemocultures. Half-maximal inhibitory concentration (IC50) values were measured from the hemocultures. All patients were infected by TcI. Significant decrease in parasitic loads was observed between Pre-Tx and Post-Tx samples, suggesting the evolution from acute to chronic phase of Chagas disease. 60% of intra-DTU-I variability was observed between Pre-Tx and Post-Tx minicircle signatures in the general population, and 43 single-nucleotide polymorphisms (SNPs) were detected in a total of 12 Tcntr-1 gene sequences, indicative of a polyclonal source of infection. SNPs in three post-Tx samples produced stop codons giving rise to putative truncated proteins or displaced open reading frames, which would render resistance genes. IC50 values varied from 5.301 ± 1.973 to 104.731 ± 4.556 µM, demonstrating a wide range of susceptibility. The poor drug response in the Pre-Tx parasite populations may be associated with the presence of naturally resistant parasite clones. Therefore, any information that can be obtained on drug susceptibility from in vitro assays, in vivo assays, or molecular characterization of natural populations of Trypanosoma cruzi becomes essential when therapeutic guidelines are designed in a given geographical area.

A Branched and Double Alpha-Gal-Bearing Synthetic Neoglycoprotein as a Biomarker for Chagas Disease.

Chagas disease (CD) is caused by the parasite Trypanosoma cruzi and affects 6-7 million people worldwide. The diagnosis is still challenging, due to extensive parasite diversity encompassing seven genotypes (TcI-VI and Tcbat) with diverse ecoepidemiological, biological, and pathological traits. Chemotherapeutic intervention is usually effective but associated with severe adverse events. The development of safer, more effective therapies is hampered by the lack of biomarker(s) (BMKs) for the early assessment of therapeutic outcomes. The mammal-dwelling trypomastigote parasite stage expresses glycosylphosphatidylinositol-anchored mucins (tGPI-MUC), whose O-glycans are mostly branched with terminal, nonreducing α-galactopyranosyl (α-Gal) glycotopes. These are absent in humans, and thus highly immunogenic and inducers of specific CD anti-α-Gal antibodies. In search for α-Gal-based BMKs, here we describe the synthesis of neoglycoprotein NGP11b, comprised of a carrier protein decorated with the branched trisaccharide Galα(1,2)[Galα(1,6)]Galß. By chemiluminescent immunoassay using sera/plasma from chronic CD (CCD) patients from Venezuela and Mexico and healthy controls, NGP11b exhibited sensitivity and specificity similar to that of tGPI-MUC from genotype TcI, predominant in those countries. Preliminary evaluation of CCD patients subjected to chemotherapy showed a significant reduction in anti-α-Gal antibody reactivity to NGP11b. Our data indicated that NGP11b is a potential BMK for diagnosis and treatment assessment in CCD patients.

Alteraciones en la producción de citosinas en respuesta a Toxoplasma gondii aparecen desde las etapas tempranas en pacientes co-infectados con VIH-1 / Alterations in the production of cytokines in response to Toxoplasma gondii appear from early stages in patients co-infected with HIV-1

Resumen Tanto el Virus de Inmunodeficiencia Humana-1 (VIH-1), como el protozoo Toxoplasma gondii son capaces de infectar al ser humano e invadir su sistema nervioso central (SNC). En individuos inmunocompetentes T. gondii causa infecciones crónicas, generalmente asintomáticas; sin embargo, la inmunodeficiencia asociada a etapas avanzadas de la infección por VIH-1, se relaciona con la pérdida del control de la infección parasitaria latente y enfermedades graves a nivel del SNC, como encefalitis toxoplásmica. Este trabajo tuvo como objetivo evaluar la evolución de la respuesta inmunitaria contra T. gondii en pacientes co-infectados con VIH-1, en distintas etapas de la infección viral. La respuesta contra T. gondii se evaluó a través de la producción in vitro de citosinas en respuesta a antígenos parasitarios, en individuos con serología positiva para VIH-1 y negativa para T. gondii (P1), positiva para VIH-1 y T. gondii (P2), negativa para VIH-1 y T. gondii (C1) y negativa para VIH-1 y positiva para T. gondii (C2). Los pacientes (P1 y P2) se agruparon en tempranos/asintomáticos (P1A, P2A) o tardíos/sintomáticos (P1B/C, P2B/C) de acuerdo a su recuento de linfocitos T CD4+ en sangre periférica (>350 o <350 células/μL, respectivamente). La infección por VIH-1, desde etapas tempranas, se asoció con una producción de IL-2, TNF-α e IFN-γ en respuesta a T. gondii significativamente menor. Estos defectos pueden entorpecer la respuesta anti-T. gondii en pacientes co-infectados, aumentando la posibilidad de reactivación de las infecciones latentes, lo que representa un riesgo para la integridad y funcionalidad del SNC.

Abstract Both HIV-1 and Toxoplasma gondii are able to invade central nervous system and affect its functionality. Advanced HIV-1 infection has been associated with defects in immune response to T. gondii, leading to reactivation of latent infections and the appearing of toxoplasmic encephalitis. This study evaluated changes in the immune response to T. gondii in different stages of HIV infection. Immune response to T. gondii was assessed studying cytokine production in response to parasite antigens in HIV-1-infected/T. gondii-noninfected (P1), HIV-1/T. gondii co-infected (P2), HIV-1-non-infected/T. gondiinon-infected (C1) and HIV-1-non-infected/T. gondii-infected (C2) individuals. Patients (P1 and P2) were divided in early/asymptomatic (P1A, P2A) or late/symptomatic (P1B/C, P2B/C) according to peripheral blood CD4+ T lymphocyte counts (>350 or <350/μL, respectively). The HIV-1 infection, from early/asymptomatic stages, was associated with significant lower production of IL-2, TNF-α and IFN-γ in response to T. gondii, when P2 patients were compared with C2 controls. These early defects may impair anti-parasitic response in co-infected patients, allowing to reactivation of parasitic latent infection, enhancing the risk of CNS damage and impairment of neurocognitive functions.

Specific Recognition of ß-Galactofuranose-Containing Glycans of Synthetic Neoglycoproteins by Sera of Chronic Chagas Disease Patients.

Chagas disease (CD) can be accurately diagnosed by detecting Trypanosoma cruzi in patients' blood using polymerase chain reaction (PCR). However, parasite-derived biomarkers are of great interest for the serological diagnosis and early evaluation of chemotherapeutic efficacy when PCR may fail, owing to a blood parasite load below the method's limit of detection. Previously, we focused on the detection of specific anti-α-galactopyranosyl (α-Gal) antibodies in chronic CD (CCD) patients elicited by α-Gal glycotopes copiously expressed on insect-derived and mammal-dwelling infective parasite stages. Nevertheless, these stages also abundantly express cell surface glycosylphosphatidylinositol (GPI)-anchored glycoproteins and glycoinositolphospholipids (GIPLs) bearing nonreducing terminal ß-galactofuranosyl (ß-Galf) residues, which are equally foreign to humans and, therefore, highly immunogenic. Here we report that CCD patients' sera react specifically with synthetic ß-Galf-containing glycans. We took a reversed immunoglycomics approach that entailed: (a) Synthesis of T. cruzi GIPL-derived Galfß1,3Manpα-(CH2)3SH (glycan G29SH) and Galfß1,3Manpα1,2-[Galfß1,3]Manpα-(CH2)3SH (glycan G32SH); and (b) preparation of neoglycoproteins NGP29b and NGP32b, and their evaluation in a chemiluminescent immunoassay. Receiver-operating characteristic analysis revealed that NGP32b can distinguish CCD sera from sera of healthy individuals with 85.3% sensitivity and 100% specificity. This suggests that Galfß1,3Manpα1,2-[Galfß1,3]Manpα is an immunodominant glycotope and that NGP32b could potentially be used as a novel CCD biomarker.

Seroprevalencia de infección por Trypanosoma cruzi en perros y gatos en la bioregión centro norte de Venezuela / Seroprevalence of Trypanosoma cruzi infection in dogs and cats in the north central bioregion of Venezuela

La enfermedad de Chagas (ECh) es una parasitosis del grupo de enfermedades desatendidas de la OMS. Endémica del continente americano, la transmisión se realiza en ciclos selvático, peridomiciliario y domiciliario. Epidemiológicamente, los caninos y felinos constituyen una fuente importante de infección y son centinelas de la transmisión. El perro es un hospedador común e importante del parásito ya que la presencia y número de caninos infectados en la vivienda del hombre constituyen factores de riesgo de transmisión doméstica de Trypanosoma cruzi. El presente estudio reporta la seroprevalencia de la infección por T. cruzi en la bioregión centro norte de Venezuela (Distrito Capital, Chichiriviche de la Costa del Estado La Guaira y parte del Estado Miranda), en 301 perros y 49 gatos empleando el ensayo inmunoenzimatico (ELISA). La prevalencia global en perros fue del 30,2 % en las tres zonas estudiadas mientras que en gatos fue de 40,8 %. Con relación al sexo de los animales, se encontró una prevalencia general de perros hembras del 27,6 % y para los perros machos del 33,1%. Los gatos machos presentaron una prevalencia mayor que las hembras en todas las localidades. Tanto en perros como en gatos la distribución de seropositividad fue mayor en animales intradomicilio. Se evidenció diferencia en los valores de ELISA-IgG para las poblaciones de perros muestreados en la localidad de Petare comparado con perros presentes en la localidad de Aricagua (perros de caza), (p=0,006). En líneas generales, esta última localidad presentó una media de densidad óptica para la prueba de ELISA-IgG de 0,959 [0,369 - 1,975]. La presencia de perros y gatos infectados es un factor de riesgo actual de infección por T. cruzi para el hombre tanto en el medio rural como en el urbano(AU)

Chagas disease (ChD) is a parasitic infection in the WHO Neglected Diseases group. Endemic to the american continent, transmission takes place in sylvatic, peridomiciliary and domestic cycles. Epidemiologically, canines and felines constitute an important source of infection and are sentinels of transmission. The dog is a common and important host of the parasite, since the presence and number of infected canines in the man's house are risk factors for domestic transmission of Trypanosoma cruzi. This study reports the seroprevalence of T. cruzi infection in the north-central bioregion of Venezuela (Capital District, Chichiriviche de la Costa, La Guaira State, and part of Miranda State), in 301 dogs and 49 cats using the immunoenzymatic assay (ELISA). The overall prevalence in dogs was 30.2 % in the three studied areas, while in cats it was 40.8 %. Regarding the sex of the animals, a general prevalence of 27.6 % for female dogs and 33.1% for male dogs was found. Male cats presented a higher prevalence than females in all localities. In both, dogs and cats, the distribution of seropositivity was greater in indoor animals. There was of a difference in ELISA-IgG values for the populations of dogs sampled in the town of Petare compared to dogs present in the town of Aricagua (hunting dogs), (p=0.006). In general, this last locality presented a mean optical density for the ELISA-IgG test of 0.959 [0.369 - 1.975]. The presence of infected dogs and cats is a current risk factor for T. cruzi infection for man in both of them in the rural and in the urban environment(AU)

Immunoinformatics and Pepscan strategies on the path of a peptide-based serological diagnosis of COVID19.

Several diagnostic tools have been developed for clinical and epidemiological assays. RT-PCR and antigen detection tests are more useful for diagnosis of acute disease, while antibody tests allow the estimation of exposure in the population. Currently, there is an urgent need for the development of diagnostic tests for COVID-19 that can be used for large-scale epidemiological sampling. Through a comprehensive strategy, potential 16 mer antigenic peptides suited for antibody-based SARS-CoV-2 diagnosis were identified. A systematic scan of the three structural proteins (S,N and M) and the non-structural proteins (ORFs) present in the SARS-CoV-2 virus was conducted through the combination of immunoinformatic methods, peptide SPOT synthesis and an immunoassay with cellulose-bound peptides (Pepscan). The Pepscan filter paper sheets with synthetic peptides were tested against pools of sera of COVID-19 patients. Antibody recognition showed a strong signal for peptides corresponding to the S, N and M proteins of SARS-CoV-2 virus, but not for the ORFs proteins. The peptides exhibiting higher signal intensity were found in the C-terminal region of the N protein. Several peptides of this region showed strong recognition with all three immunoglobulins in the pools of sera. The differential reactivity observed between the different immunoglobulin isotypes (IgA, IgM and IgG) within different regions of the S and N proteins, can be advantageous for ensuring accurate diagnosis of all infected patients, with different times of exposure to infection. Few peptides of the M protein showed antibody recognition and no recognition was observed for peptides of the ORFs proteins.

Characterization and Follow-Up of Trypanosoma cruzi Natural Populations Refractory to Etiological Chemotherapy in Oral Chagas Disease Patients.

We aimed to characterize the genetic constitution of natural T. cruzi populations involved in an Oral Chagas Disease (OCD) outbreak at a rural school of the community of Chichiriviche de la Costa, Venezuela, which affected patients did not respond to the etiological treatment. Peripheral blood samples and/or hemocultures were obtained from twenty-nine OCD patients at time of diagnosis or along nine years of Post-treatment (Tx) follow-up. The IgG serology, T. cruzi discrete typing units (DTU), satellite DNA-qPCR parasitic loads, and minicircle signatures were determined at Pre-Tx and after Tx. The serological titles and parasitic loads changed after treatment, with a significant decrease of IgG titers (Spearman's r value= -0.961) and median parasite loads from 2.869 [IQR = 2.113 to 3.720] to 0.105 [IQR = -1.147 to 1.761] log10 par eq. /mL at Pre-Tx and Post-Tx, respectively, suggesting infection evolution from acute to chronic phase, without seroconversion or parasitological eradication, which was indicative of treatment failure. All patients were infected with T. cruzi DTU I populations. At Pre-Tx their median Jaccard genetic distances were 0.775 [IQR = 0.708 to 0.882], decreasing in genetic variability towards the end of follow-up (Mann-Whitney U test p= 0.0031). Interestingly, no Post-Tx minicircle signature was identical to its Pre-Tx counterpart population in a same patient, revealing selection of parasite subpopulations between the primary infection and Post-Tx. The parasitic populations isolated from hemocultures showed a lower number of bands in the minicircle signatures with respect to the signatures obtained directly from the patients' blood samples, demonstrating a process of parasitic selection and reduction of the population variability that initially infected the patients. Decrease of parasitic loads after treatment as well as Pre- and Post-Tx intra-TcI diversity might be a consequence of both, natural evolution of the acute infection to the chronic phase and persistence of refractory populations due to Tx selection.

Toward the Establishment of a Single Standard Curve for Quantification of Trypanosoma cruzi Natural Populations Using a Synthetic Satellite Unit DNA Sequence.

Accurate diagnostic tools and surrogate markers of parasitologic response to treatment are needed for managing Chagas disease. Quantitative real-time PCR (qPCR) is used for treatment monitoring, but variability in copy dosage and sequences of molecular target genes among different Trypanosoma cruzi strains limit the precision of quantitative measures. To improve qPCR quantification accuracy, we designed and evaluated a synthetic DNA molecule containing a satellite DNA (satDNA) repeat unit as standard for quantification of T. cruzi loads in clinical samples, independently of the parasite strain. Probit regression analysis established for Dm28c (TcI) and CL-Brener (TcVI) stocks similar 95% limit of detection values [0.903 (0.745 to 1.497) and 0.667 (CI, 0.113 to 3.927) copy numbers/µL, respectively] when synthetic DNA was the standard for quantification, allowing direct comparison of loads in samples infected with different discrete typing units. This standard curve was evaluated in 205 samples (38 acute oral and 19 chronic Chagas disease patients) from different geographical areas infected with various genotypes, including samples obtained during treatment follow-up; high agreement with parasitic load trends using standard curves based on DNA extracted from spiked blood with counted parasites was obtained. This qPCR-based quantification strategy will be a valuable tool in phase 3 clinical trials, to follow up patients under treatment or at risk of reactivation, and in experimental models using different parasite strains.

Trypanosoma cruzi loop-mediated isothermal amplification (Trypanosoma cruzi Loopamp) kit for detection of congenital, acute and Chagas disease reactivation.

A Trypanosoma cruzi Loopamp kit was recently developed as a ready-to-use diagnostic method requiring minimal laboratory facilities. We evaluated its diagnostic accuracy for detection of acute Chagas disease (CD) in different epidemiological and clinical scenarios. In this retrospective study, a convenience series of clinical samples (venous blood treated with EDTA or different stabilizer agents, heel-prick blood in filter paper or cerebrospinal fluid samples (CSF)) from 30 infants born to seropositive mothers (13 with congenital CD and 17 noninfected), four recipients of organs from CD donors, six orally-infected cases after consumption of contaminated guava juice and six CD patients coinfected with HIV at risk of CD reactivation (N = 46 patients, 46 blood samples and 1 CSF sample) were tested by T. cruzi Loopamp kit (Tc LAMP) and standardized quantitative real-time PCR (qPCR). T. cruzi Loopamp accuracy was estimated using the case definition in the different groups as a reference. Cohen's kappa coefficient (κ) was applied to measure the agreement between Tc LAMP (index test) and qPCR (reference test). Sensitivity and specificity of T. cruzi Loopamp kit in blood samples from the pooled clinical groups was 93% (95% CI: 77-99) and 100% (95% CI: 80-100) respectively. The agreement between Tc LAMP and qPCR was almost perfect (κ = 0.92, 95% CI: 0.62-1.00). The T. cruzi Loopamp kit was sensitive and specific for detection of T. cruzi infection. It was carried out from DNA extracted from peripheral blood samples (via frozen EDTA blood, guanidine hydrochloride-EDTA blood, DNAgard blood and dried blood spots), as well as in CSF specimens infected with TcI or TcII/V/VI parasite populations. The T. cruzi Loopamp kit appears potentially useful for rapid detection of T. cruzi infection in congenital, acute and CD reactivation due to HIV infection.

Enfermedad de Chagas y el binomio madre-hijo / Chagas disease and the mother-son binomy

La infección por Trypanosoma cruzi está garantizada por la presencia del parásito en muchos géneros animales incluido el hombre. Este a su vez, no solo adquiere el parásitoa través del vector (cutánea, por mucosas, oral) o por secreciones de didelfidos o accidentalmente por manipulación de material biológico infectante,sino también por la trasmisión hombre-hombre la cual aumenta la diseminación de la Enfermedad de Chagas aunque en menor proporción (trasmisión congénita, transfusional o por trasplante de tejidos). El parásito alcanza al feto in utero principalmente por su capacidad de atravesar la placenta especialmente después de la semana 20 cuando la barrera placentaria se adelgaza progresivamente. Sin embargo solo del 1 al 10% de los niños nacidos de madres con Enfermedad de Chagas desarrollan infección aguda variando de acuerdo al país, edad gestacional, al genotipo y carga del parásito entre varios factores. La clínica del neonato con T. cruzi va desde casos asintomáticos, bajo peso, prematuridad, hepatoesplenomegalia, dificultad respiratoria,hastael desenlace fatal. La prevención se basa en la detección por serología y tratamiento oportuno en niñas y mujeres antes del embarazo ya que los antiparasitarios específicos producen efectos adversos y en principio están contraindicados durante el embarazo. En cambio el tratamiento está indicado en el niño en cualquier momento cuando se demuestre la patología. El despistaje de la infección por T. cruzi debería ser obligatorio en toda Latinoamérica y en toda mujer latinoamericana en el mundo a fin de estar preparado para la atención postparto al infante y a la madre(AU)

Infection with Trypanosoma cruzi is guaranteed by the presence of the parasite in many animal genera including man. This in turn, not only acquires the parasite by contact with a vector (skin, mucoses and oral transmission) or by secretions of didelfides or accidentally by manipulation of infecting biological material, but also by man-man transmission which increases the spread of Chagas disease (congenital, transfusion or tissue transplant transmission). The parasite reaches the fetus in utero mainly due to its ability to cross the placenta especially after week 20 when the placental barrier becomes progressively thinner. However, only 1 to 10% of children born from mothers with Chagas disease develop acute infection, varying according to country, gestational age, genotype, and parasite load among various factors. The clinic of the neonate with T. cruzi ranges from asymptomatic cases, low weight, prematurity, hepatosplenomegaly, respiratory distress to the fatal outcome. Prevention is based on the detection by serology and timely treatment in girls and women before pregnancy since specific antiparasitic drugs produce adverse effects and are in principle contraindicated during pregnancy. Instead, treatment is indicated in the child at any time when the pathology is demonstrated. The screening of T. cruzi infection should be mandatory in all Latin America and in all Latin American women in the world in order to be prepared for the postpartum care of the infant and the mother(AU)

Toxoplasmosis y Enfermedad de Chagas: seroprevalencia y factores de riesgo en embarazadas del HUC

La Toxoplasmosis y la Enfermedad de Chagas (ECh) son infecciones parasitarias frecuentes en Latinoamérica, capaces de ser transmitidas verticalmente durante el embarazo. Este trabajo tiene como objetivo determinar la seroprevalencia ante Trypanosoma cruzi (T. cruzi) y Toxoplasma gondii (T. gondii), en las embarazadas de la consulta prenatal del Ambulatorio Docente del Hospital Universitario de Caracas. Estudio analítico, prospectivo de corte transversal, realizado en 300 pacientes, en el lapso comprendido entre enero 2018 ­ marzo 2019. El 31,66 % de la población estudiada presentó seropositividad para anticuerpos IgG específicos para T. gondii, avidez de IgG mayor al 50 % e IgM negativa en todas, resultados compatibles con la fase crónica de la infección. Al correlacionar con los factores de riesgo habituales para la transmisión de T. gondii destacaron el contacto con heces de gato (46,3 %) y el consumo de agua directamente del grifo (32,6 %). En el caso de la ECh se demostró la presencia de factores de riesgo en la población estudiada, como contacto con triatominos (51,45 %) y viviendas cercanas a vegetación (49 %), sin embargo, solo una embarazada (0,33 %) demostró seropositividad para T. cruzi sin presentar relación con los factores de riesgo estudiados. Se evidenció una seroprevalencia muy frecuente para T. gondii y menor para T. cruzi, con factores de riesgo para la trasmisión vectorial cutánea y oral muy altos, constituyéndo una amenaza tanto para la embarazada como para al feto. Se recomienda educar a la población para reducir su exposición a factores de riesgo.

Toxoplasmosis and Chagas Disease (ChD) are frequent parasitic infections in Latin America, capables of vertical transmission during pregnancy. The purpose of this article is to determine the seroprevalence against Trypanosoma cruzi (T. cruzi) and Toxoplasma gondii (T. gondii), in pregnant women attending the prenatal clinic of the "Hospital Universitario de Caracas". Analytical, prospective study of a transversal cohort, carried out in 300 patients, during the period January 2018 - March 2019. The 31.66 % of the analyzed population showed seropositivity for IgG specific antibodies for T. gondii, all displaying an avidity IgG greater than 50 % and negative IgM, corresponding to a chronic stage of the infection. When correlating with the usual risk factors for the transmission of T. gondii, it was highlighted the presence of contact with cat feces (46.3 %) and the consumption of water directly from the tap (32.6 %). While with Chagas Disease (ChD), the presence of risk factors for acquiring the infection were highly demonstrated in the population, such as contact with triatomines (51.45 %) and living close to vegetation (49 %), however, only one pregnant woman (0.33 %) presented seropositivity for T. cruzi, without being related to the known risk factors. We conclude that T. gondii presents a high seroprevalence and T. cruzi an infrequent seroprevalence in the covered population, with high risk factors for cutaneous and oral vector transmission, representing a threat for the mother and the fetus. We recommend educating the population to reduce their exposure to risk factors.

Venezuela's humanitarian crisis, resurgence of vector-borne diseases, and implications for spillover in the region.

In the past 5-10 years, Venezuela has faced a severe economic crisis, precipitated by political instability and declining oil revenue. Public health provision has been affected particularly. In this Review, we assess the impact of Venezuela's health-care crisis on vector-borne diseases, and the spillover into neighbouring countries. Between 2000 and 2015, Venezuela witnessed a 359% increase in malaria cases, followed by a 71% increase in 2017 (411 586 cases) compared with 2016 (240 613). Neighbouring countries, such as Brazil, have reported an escalating trend of imported malaria cases from Venezuela, from 1538 in 2014 to 3129 in 2017. In Venezuela, active Chagas disease transmission has been reported, with seroprevalence in children (<10 years), estimated to be as high as 12·5% in one community tested (n=64). Dengue incidence increased by more than four times between 1990 and 2016. The estimated incidence of chikungunya during its epidemic peak is 6975 cases per 100 000 people and that of Zika virus is 2057 cases per 100 000 people. The re-emergence of many vector-borne diseases represents a public health crisis in Venezuela and has the possibility of severely undermining regional disease elimination efforts. National, regional, and global authorities must take action to address these worsening epidemics and prevent their expansion beyond Venezuelan borders.

Long-term comparative pharmacovigilance of orally transmitted Chagas disease: first report.

BACKGROUND: Two old drugs are the only choice against Trypanosoma cruzi and little is known about their secondary effects in the acute stage of oral-transmitted Chagas disease (ChD). METHODS: A cross-sectional analytical surveillance study was conducted in a sizable cohort of patients seen during the largest acute foodborne ChD microepidemic registered so far. Individuals were treated with benznidazole (BNZ) or nifurtimox (NFX). 'Common Terminology Criteria for Adverse Events' was assessed to categorize side effects according to severity. RESULTS: Out of 176 treatments applied, 79% had one or more adverse effects, which predominated in adults (97.8%) as compared to children (75.5%). Risk of side effects with NFX was significantly higher than BNZ. Four adults and a child treated with NFX had severe side effects (pulmonary infarction, facial paralysis, neutropenia, blurred vision, bone marrow hypoplasia) warranting hospitalization, and drug suspension. Adverse effects frequently reported with NFX were abdominal pain, hyporexia, weight loss, headache, nausea and lymphocytosis, whereas skin rash, neurosensory effects, hyporexia, fatigue, pyrosis, abdominal pain and eosinophilia were observed with BNZ. CONCLUSIONS: Frequency and severity of side effects during treatment of acute oral infection by T. cruzi demand direct supervision and close follow-up, even in those asymptomatic, to prevent life-threatening situations.

Distribución de moluscos (Gastropoda) de importancia médica en Venezuela / Distribution of freshwater mollusks (Gastropoda) of medical importance in Venezuela

El presente trabajo describe la distribución geográfica actual de las principales especies de caracoles de agua dulce incriminadas como hospedadoras intermediarias de Schistosoma mansoni (4 especies de Biomphalaria), Fasciola hepatica (4 especies de Galba y Pseudosuccinea columella) y Paragonimus sp. (Aroapyrgus vivens) en Venezuela. Adicionalmente, se discute el status epidemiológico así como el hábitat de ocurrencia de cada una de estas especies, a fin de brindar información base para la vigilancia, manejo y control de los hospedadores intermediarios que participan en los ciclos vitales de los agentes causales de la esquistosomiasis, fascioliasis y paragonimiasis, que constituyen enfermedades desatendidas actualmente en Venezuela.

This study describes the current distribution patterns of the main species of freshwater mollusks incriminated as intermediate hosts of Schistosoma mansoni (Biomphalaria, 4 species), Fasciola hepatica (Galba, 4 species and Pseudosuccinea columella), and Paragonimus sp. (Aroapyrgus vivens) in Venezuela. Additionally, the epidemiological status and the main aquatic habitats of each species are discussed in order to bring basic information to help the surveillance and control of these neglected tropical diseases in Venezuela.

Orally-transmitted Chagas disease: Epidemiological, clinical, serological and molecular outcomes of a school microepidemic in Chichiriviche de la Costa, Venezuela.

Oral transmission of Trypanosoma cruzi is a frequent cause of acute Chagas disease (ChD). In the present cross-sectional study, we report the epidemiological, clinical, serological and molecular outcomes of the second largest outbreak of oral ChD described in the literature. It occurred in March 2009 in Chichiriviche de la Costa, a rural seashore community at the central littoral in Venezuela. The vehicle was an artisanal guava juice prepared at the local school and Panstrongylus geniculatus was the vector involved. TcI genotype was isolated from patients and vector; some showed a mixture of haplotypes. Using molecular markers, parasitic loads were high. Eighty-nine cases were diagnosed, the majority (87.5%) in school children 6-15 years of age. Frequency of symptomatic patients was high (89.9%) with long-standing fever in 87.5%; 82.3% had pericardial effusion detected by echocardiogram and 41% had EKG abnormalities. Three children, a pregnant woman and her stillborn child died (5.6% mortality). The community was addressed by simultaneous determination of specific IgG and IgM, confirmed with indirect hemagglutination and lytic antibodies. Determination of IgG and IgA in saliva had low sensitivity. No individual parasitological or serological technique diagnosed 100% of cases. Culture and PCR detected T. cruzi in 95.5% of examined individuals. Based on the increasing incidence of oral acute cases of ChD, it appears that food is becoming one of the most important modes of transmission in the Amazon, Caribbean and Andes regions of America.