Metataxomics reveals Blastocystis subtypes mixed infections in Colombian children.

Blastocystis sp., is an intestinal protist with a broad host range and a high prevalence in human populations worldwide, even in developed Western countries. The publication of conflicting evidence has divided the scientific community about the pathogenic role of this parasite. Even though, genetic studies on Blastocystis sp. revealed associations between genotypes and different pathogenic profiles. Conventionally, the detection of this parasite is based on microscopic or PCR methods, which offer meager or null performance in detecting mixed infections. In this work, we applied a metataxonomic NGS approach targeting the V4 region of the eukaryotic SSU-rRNA gene and classical phylogenetic methods. This approach allowed us to detect Blastocystis sp. in stool samples from infected children living in an urban setting in the city of Medellin attending the same daycare center. Phylogenetic analysis identified the subtypes present in the children as ST1, ST2, and ST3. Besides, mixed infections of subtypes ST1 + ST3 were spotted in 16% of the analyzed stool samples.

Evaluation of new Toxocara canis chimeric antigens as an alternative to conventional TES-Ag for anti-Toxocara antibodies detection.

Human toxocariasis is one of the neglected helminthiases and it is caused by the zoonotic roundworm species Toxocara canis and Toxocara cati. Diagnosis of human toxocariasis is based on the combination of clinical, parasitological, and epidemiological criteria, as well as serology tests that detect anti-Toxocara antibodies. Notwithstanding, due to the absence of pathognomonic symptoms and signs of the disease, serology is the key evidence to support a conclusive diagnosis. TES-ELISA is the most widely used serological test for diagnosis. However, cross-reaction of TES antigens with antibodies produced to other helminth antigens is a major drawback for its application in countries with high parasitic prevalence. T. canis recombinant antigens have been described as an alternative to native TES for diagnosis. Nevertheless, the selection of antigenic proteins is a complex process that requires validation. In this paper, we developed an eGFP carrier-based system to express and purify blocks of recombinant polypeptides of T. canis antigenic proteins. Intense cross-reaction polypeptides were detected by Immunoblot and avoided to finally produce a chimeric prototype protein. Additionally, a control chimeric protein that harbors the complete tested proteins was produced. Purified chimeric antigens were tested in ELISA and Immunoblot assays with 310 sera samples of negative and positive control individuals. Our results showed that chimeric rCHITC0 and rCHITC1 antigens (with sensitivities of 62% 58%, 38% and 16% in IB-rCHITC0, ELISA-rCHITC0, ELISA-rCHITC1 and IB-rCHITC1 respectively for OLMS) can perform better in terms of specificity (being 91%, 89%, 87% and 76% for ELISA-rCHITC1, IB-rCHITC1, ELISA-rCHITC0 and IB-rCHITC0 respectively for OLMS) than T. canis TES-ELISA (with 61% specificity), giving a higher signal with serum samples of infected individuals as well the possibility to discriminate false positive cases with other parasitic infections. Our data suggest that T. canis chimeric proteins, represent candidate antigens for phase II studies.

Multilocus Sequence Typing helps understand the genetic diversity of Cryptosporidium hominis and Cryptosporidium parvum isolated from Colombian patients.

Multilocus Sequence Typing has become a useful tool for the study of the genetic diversity and population structure of different organisms. In this study, a MLST approach with seven loci (CP47, MS5, MS9, MSC6-7, TP14, and gp60) was used to analyze the genetic diversity of Cryptosporidium hominis and Cryptosporidium parvum isolated from 28 Colombian patients. Five Cryptosporidium species were identified: C. hominis, C. parvum, Cryptosporidium felis, Cryptosporidium meleagridis, and Cryptosporidium suis. Unilocus gp60 analysis identified four allelic families for C. hominis (Ia, Ib, Id, and Ie) and two for C. parvum (IIa and IIc). There was polymorphic behavior of all markers evaluated for both C. hominis and C. parvum, particularly with the CP47, MS5, and gp60 markers. Phylogenetic analysis with consensus sequences (CS) of the markers showed a taxonomic agreement with the results obtained with the 18S rRNA and gp60 gene. Additionally, two monophyletic clades that clustered the species C. hominis and C. parvum were detected, with a higher number of subclades within the monophyletic groups compared to those with the gp60 gene. Thirteen MLG were identified for C. hominis and eight for C. parvum. Haplotypic and nucleotide diversity were detected, but only the latter was affected by the gp60 exclusion from the CS analysis. The gene fixation index showed an evolutionary closeness between the C. hominis samples and a less evolutionary closeness and greater sequence divergence in the C. parvum samples. Data obtained in this work support the implementation of MLST analysis in the study of the genetic diversity of Cryptosporidium, considering the more detailed information that it provides, which may explain some genetic events that with an unilocus approach could not be established. This is the first multilocus analysis of the intra-specific variability of Cryptosporidium from humans in South America.

Cryptosporidium hominis Phylogenomic Analysis Reveals Separate Lineages With Continental Segregation.

Cryptosporidium is a leading cause of waterborne outbreaks globally, and Cryptosporidium hominis and C. parvum are the principal cause of human cryptosporidiosis on the planet. Thanks to the advances in Next-Generation Sequencing (NGS) sequencing and bioinformatic software development, more than 100 genomes have been generated in the last decade using a metagenomic-like strategy. This procedure involves the parasite oocyst enrichment from stool samples of infected individuals, NGS sequencing, metagenomic assembly, parasite genome computational filtering, and comparative genomic analysis. Following this approach, genomes of infected individuals of all continents have been generated, although with striking different quality results. In this study, we performed a thorough comparison, in terms of assembly quality and purity, of 100+ de novo assembled genomes of C. hominis. Remarkably, after quality genome filtering, a comprehensive phylogenomic analysis allowed us to discover that C. hominis encompasses two lineages with continental segregation. These lineages were named based on the observed continental distribution bias as C. hominis Euro-American (EA) and the C. hominis Afro-Asian (AA) lineages.

Prevalence of intestinal parasites in a cohort of HIVinfected patients from Antioquia, Colombia. / Prevalencia de parásitos intestinales en una cohorte de pacientes positivos para HIV en Antioquia, Colombia

INTRODUCTION: HIV infection is still a public health problem worldwide and co-infections with other infectious agents including intestinal parasites are of particular concern, mainly in developing countries like Colombia. OBJECTIVE: To conduct a cross-sectional study in patients attending an HIV care program in Antioquia given that there have been few intestinal parasites prevalence studies among the HIV population in the country. MATERIAL AND METHODS: We evaluated stool samples from 192 patients by direct wet mount and concentration, modified Ziehl Neelsen staining, and agar plate culture. Univariate and correlation analyses were done to explore the association between socio-demographic and clinical characteristics and parasitological data. RESULTS: The overall prevalence of intestinal parasites in HIV-positive subjects was 29.2% (56/192; 95% CI: 22.8% - 35.6%). Entamoeba histolytica/dispar/moshkosvkii with 13.0% (25/192; 95% CI: 8.2% - 17.8%) and Blastocystis with 12.0% (23/192; 95% CI: 7.4% - 16.6%) were the most frequent. Opportunistic parasites like Cryptosporidium spp. and Cystoisospora belli were less prevalent, each one with 0.5% of positive samples (1/192; 95% CI: 0.1% - 1.5%). Commensal protozoa were also detected with a prevalence of 18.8% (36/192; 95% CI: 13.3% - 24.3%). Most of the individuals in the study had a controlled viral load and an LTCD4 count greater than 200 cel/µL. A small percentage (9.3%) had diarrhea. Bivariate analysis and multivariate logistic regression showed that only age and having pets had a significant association with intestinal parasites in this cohort. CONCLUSIONS: Our results confirmed that the evaluated population is at high risk of intestinal parasite infection, which highlights the need for routine screening of gastrointestinal parasites to provide prompt treatment and reduce possible complications.

Introducción. La infección por HIV y las coinfecciones con otros agentes infecciosos, incluidos los parásitos intestinales, son motivo de especial preocupación en países en desarrollo como Colombia. Objetivo. Hacer un estudio transversal en pacientes que asisten a un programa de atención de HIV en el departamento de Antioquia, dado que los estudios de prevalencia de parásitos intestinales en la población con HIV son escasos en el país. Materiales y métodos. Se evaluaron 192 muestras de materia fecal mediante examen coprológico directo y por concentración, tinción de Ziehl-Neelsen modificada, y aislamiento en agar. Se hicieron análisis univariados y de correlación, para explorar la asociación entre las características sociodemográficas y clínicas, y los datos parasitológicos. Resultados. La prevalencia global de parásitos intestinales en pacientes positivos para VIH fue del 29.2 % (56/192; IC95% 22.8-35.6 %), siendo Entamoeba histolytica/dispar/moshkosvkii, con 13.0 % (25/192; IC95% 8.2-17.8 %), y Blastocystis, con 12.0 % (23/192; IC95% 7.4-16.6 %), los mas frecuentes. Los parásitos oportunistas Cryptosporidium spp. y Cystoisospora belli fueron menos prevalentes, cada uno con 0.5 % (1/192; IC95% 0.1-1.5 %) de muestras positivas. También, se detectaron protozoos comensales, con una prevalencia del 18,8 % (36/192; IC95% 13,3-24,3 %). La mayoría de los individuos tenía una carga viral controlada y un recuento de linfocitos T CD4 superior a 200 células/µl. Un pequeño porcentaje (9,3 %) presentó diarrea. La edad y el tener mascotas mostraron una asociación significativa con la presencia de parásitos intestinales. Conclusión. Se confirmó que la población evaluada tiene un alto riesgo de infección por parásitos intestinales, lo que resalta la necesidad de un protocolo de diagnóstico para el cribado de dichos agentes, con el fin de brindar un tratamiento rápido y reducir las posibles complicaciones.

Prevalence of intestinal parasites in a cohort of HIV- infected patients from Antioquia, Colombia / Prevalencia de parásitos intestinales en una cohorte de pacientes positivos para HIV en Antioquia, Colombia

Abstract | Introduction: HIV infection is still a public health problem worldwide and co-infections with other infectious agents including intestinal parasites are of particular concern, mainly in developing countries like Colombia. Objective: To conduct a cross-sectional study in patients attending an HIV care program in Antioquia given that there have been few intestinal parasites prevalence studies among the HIV population in the country. Material and methods: We evaluated stool samples from 192 patients by direct wet mount and concentration, modified Ziehl Neelsen staining, and agar plate culture. Univariate and correlation analyses were done to explore the association between socio-demographic and clinical characteristics and parasitological data. Results: The overall prevalence of intestinal parasites in HIV-positive subjects was 29.2% (56/192; 95% CI: 22.8% - 35.6%). Entamoeba histolytica/dispar/moshkosvkii with 13.0% (25/192; 95% CI: 8.2% - 17.8%) and Blastocystis with 12.0% (23/192; 95% CI: 7.4% -16.6%) were the most frequent. Opportunistic parasites like Cryptosporidium spp. and Cystoisospora belli were less prevalent, each one with 0.5% of positive samples (1/192; 95% CI: 0.1% - 1.5%). Commensal protozoa were also detected with a prevalence of 18.8% (36/192; 95% CI: 13.3% - 24.3%). Most of the individuals in the study had a controlled viral load and an LTCD4 count greater than 200 cel/µL. A small percentage (9.3%) had diarrhea. Bivariate analysis and multivariate logistic regression showed that only age and having pets had a significant association with intestinal parasites in this cohort. Conclusions: Our results confirmed that the evaluated population is at high risk of intestinal parasite infection, which highlights the need for routine screening of gastrointestinal parasites to provide prompt treatment and reduce possible complications.

Resumen | Introducción. La infección por HIV y las coinfecciones con otros agentes infecciosos, incluidos los parásitos intestinales, son motivo de especial preocupación en países en desarrollo como Colombia. Objetivo. Hacer un estudio transversal en pacientes que asisten a un programa de atención de HIV en el departamento de Antioquia, dado que los estudios de prevalencia de parásitos intestinales en la población con HIV son escasos en el país. Materiales y métodos. Se evaluaron 192 muestras de materia fecal mediante examen coprológico directo y por concentración, tinción de Ziehl-Neelsen modificada, y aislamiento en agar. Se hicieron análisis univariados y de correlación, para explorar la asociación entre las características sociodemográficas y clínicas, y los datos parasitológicos. Resultados. La prevalencia global de parásitos intestinales en pacientes positivos para VIH fue del 29.2 % (56/192; IC95% 22.8-35.6 %), siendo Entamoeba histolytica/dispar/moshkosvkii, con 13.0 % (25/192; IC95% 8.2-17.8 %), y Blastocystis, con 12.0 % (23/192; IC95% 7.4-16.6 %), los mas frecuentes. Los parásitos oportunistas Cryptosporidium spp. Y Cystoisospora belli fueron menos prevalentes, cada uno con 0.5 % (1/192; IC95% 0.1-1.5 %) de muestras positivas. También, se detectaron protozoos comensales, con una prevalencia del 18,8 % (36/192; IC95% 13,3-24,3 %). La mayoría de los individuos tenía una carga viral controlada y un recuento de linfocitos T CD4 superior a 200 células/μl. Un pequeño porcentaje (9,3 %) presentó diarrea. La edad y el tener mascotas mostraron una asociación significativa con la presencia de parásitos intestinales. Conclusión. Se confirmó que la población evaluada tiene un alto riesgo de infección por parásitos intestinales, lo que resalta la necesidad de un protocolo de diagnóstico para el cribado de dichos agentes, con el fin de brindar un tratamiento rápido y reducir las posibles complicaciones.

Chronic Cystoisospora belli infection in a Colombian patient living with HIV and poor adherence to highly active antiretroviral therapy. / Infección crónica por Cystoisospora belli en un paciente colombiano con HIV y cumplimiento deficiente de la terapia antirretroviral de gran actividad

Cystoisospora belli is an intestinal Apicomplexan parasite associated with diarrheal illness and disseminated infections in humans, mainly immunocompromised individuals such as those living with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). An irregular administration of highly active antiretroviral therapy (HAART) in HIV patients may increase the risk of opportunistic infections like cystoisosporiasis. We describe here a case of C. belli infection in a Colombian HIV patient with chronic gastrointestinal syndrome and poor adherence to HAART. His clinical and parasitological cure was achieved with trimethoprim-sulfamethoxazole treatment. Although a reduction in the number of C. belli cases has been observed since the use of HAART, this parasite still has to be considered as a differential diagnosis of diarrheal disease in HIV/AIDS patients. Effective interventions enhancing adherence to HAART should be included in HIV patient care programs.

Cystoisospora belli es un parásito intestinal del filo Apicomplexa asociado con enfermedades diarreicas e infecciones diseminadas en humanos, principalmente en individuos inmunocomprometidos, como aquellos infectados con el virus de la inmunodeficiencia humana (HIV) o el síndrome de inmunodeficiencia adquirida (sida). El cumplimiento inadecuado de la terapia antirretroviral de gran actividad (TARGA) puede aumentar el riego de infecciones oportunistas, incluida la cistoisosporiasis. Se describe el caso de infección por C. belli en un paciente colombiano con HIV, que presentó un síndrome gastrointestinal crónico e incumplía el tratamiento con la TARGA. Después del diagnóstico parasitológico, el paciente fue tratado con trimetoprimsulfametoxazol, lográndose la recuperación clínica y la cura parasitológica. Aunque se ha observado una reducción en el número de casos de C. belli desde la implementación de la TARGA, este parásito aún debe considerarse en el diagnóstico diferencial de las enfermedades diarreicas en pacientes con HIV/sida. Los programas de atención deben incluir intervenciones efectivas que potencien el cumplimiento de la TARGA en estos pacientes.

Chronic Cystoisospora belli infection in a Colombian patient living with HIV and poor adherence to highly active antiretroviral therapy / Infección crónica por Cystoisospora belli en un paciente colombiano con HIV y cumplimiento deficiente de la terapia antirretroviral de gran actividad

Abstract | Cystoisospora belli is an intestinal Apicomplexan parasite associated with diarrheal illness and disseminated infections in humans, mainly immunocompromised individuals such as those living with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). An irregular administration of highly active antiretroviral therapy (HAART) in HIV patients may increase the risk of opportunistic infections like cystoisosporiasis. We describe here a case of C. belli infection in a Colombian HIV patient with chronic gastrointestinal syndrome and poor adherence to HAART. His clinical and parasitological cure was achieved with trimethoprim-sulfamethoxazole treatment. Although a reduction in the number of C. belli cases has been observed since the use of HAART, this parasite still has to be considered as a differential diagnosis of diarrheal disease in HIV/AIDS patients. Effective interventions enhancing adherence to HAART should be included in HIV patient care programs.

Resumen | Cystoisospora belli es un parásito intestinal del filo Apicomplexa asociado con enfermedades diarreicas e infecciones diseminadas en humanos, principalmente en individuos inmunocomprometidos, como aquellos infectados con el virus de la inmunodeficiencia humana (HIV) o el síndrome de inmunodeficiencia adquirida (sida). El cumplimiento inadecuado de la terapia antirretroviral de gran actividad (TARGA) puede aumentar el riego de infecciones oportunistas, incluida la cistoisosporiasis. Se describe el caso de infección por C. belli en un paciente colombiano con HIV, que presentó un síndrome gastrointestinal crónico e incumplía el tratamiento con la TARGA. Después del diagnóstico parasitológico, el paciente fue tratado con trimetoprim-sulfametoxazol, lográndose la recuperación clínica y la cura parasitológica. Aunque se ha observado una reducción en el número de casos de C. belli desde la implementación de la TARGA, este parásito aún debe considerarse en el diagnóstico diferencial de las enfermedades diarreicas en pacientes con HIV/sida. Los programas de atención deben incluir intervenciones efectivas que potencien el cumplimiento de la TARGA en estos pacientes.

Comparative genomic analysis of the principal Cryptosporidium species that infect humans.

Cryptosporidium parasites are ubiquitous and can infect a broad range of vertebrates and are considered the most frequent protozoa associated with waterborne parasitic outbreaks. The intestine is the target of three of the species most frequently found in humans: C. hominis, C. parvum, and. C. meleagridis. Despite the recent advance in genome sequencing projects for this apicomplexan, a broad genomic comparison including the three species most prevalent in humans have not been published so far. In this work, we downloaded raw NGS data, assembled it under normalized conditions, and compared 23 publicly available genomes of C. hominis, C. parvum, and C. meleagridis. Although few genomes showed highly fragmented assemblies, most of them had less than 500 scaffolds and mean coverage that ranged between 35X and 511X. Synonymous single nucleotide variants were the most common in C. hominis and C. meleagridis, while in C. parvum, they accounted for around 50% of the SNV observed. Furthermore, deleterious nucleotide substitutions common to all three species were more common in genes associated with DNA repair, recombination, and chromosome-associated proteins. Indel events were observed in the 23 studied isolates that spanned up to 500 bases. The highest number of deletions was observed in C. meleagridis, followed by C. hominis, with more than 60 species-specific deletions found in some isolates of these two species. Although several genes with indel events have been partially annotated, most of them remain to encode uncharacterized proteins.

Contrasting microbiota profiles observed in children carrying either Blastocystis spp. or the commensal amoebas Entamoeba coli or Endolimax nana.

Recent studies have shown how intestinal parasites can modulate gut microbiota. This observation is not surprising since the human intestinal lumen, like any other niche, is a battlefield of microbial competition, and Eukaryotes can affect bacterial populations. Intestinal pathogenic protist has been associated with reshaping the microbial community structure; however, the interactions between the colonic bacterial communities and parasites like Blastocystis spp., Entamoeba coli, and Endolimax nana have been poorly studied. In this work, we studied the distal intestinal bacterial microbiota of 49 children attending 7 public daycare centers in Medellin, Colombia, and compared the bacterial microbiota structure in the presence or absence of the protists Blastocystis spp., E. coli, and E. nana. Parasite colonization was associated with an increase in bacterial richness. Moreover, Blastocystis spp. presented a positive relationship with Prevotella, since this bacterium was selectively enriched in children carrying it. Remarkably, the E. coli colonized children showed a microbial profile that was closer to uninfected controls, although some bacterial taxa displayed to be enriched. This is the case for Akkermansia, which showed to be favored in E. coli colonized individuals, while notably reduced in the Blastocystis spp. parasitized group.

Diagnosis of human and canine Brucella canis infection: development and evaluation of indirect enzyme-linked immunosorbent assays using recombinant Brucella proteins.

Brucella canis, a Gram-negative coccobacilli belonging to the genus Brucellae, is a pathogenic bacterium that can produce infections in dogs and humans. Multiple studies have been carried out to develop diagnostic techniques to detect all zoonotic Brucellae. Diagnosis of Brucella canis infection is challenging due to the lack of highly specific and sensitive diagnostic assays. This work was divided in two phases: in the first one, were identified antigenic proteins in B. canis that could potentially be used for serological diagnosis of brucellosis. Human sera positive for canine brucellosis infection was used to recognize immunoreactive proteins that were then identified by performing 2D-GEL and immunoblot assays. These spots were analyzed using MALDI TOF MS and predicted proteins were identified. Of the 35 protein spots analyzed, 14 proteins were identified and subsequently characterized using bioinformatics, two of this were selected for the next phase. In the second phase, we developed and validated an indirect enzyme-linked immunosorbent assays using those recombinant proteins: inosine 5' phosphate dehydrogenase, pyruvate dehydrogenase E1 subunit beta (PdhB) and elongation factor Tu (Tuf). These genes were PCR-amplified from genomic DNA of B. canis strain Oliveri, cloned, and expressed in Escherichia coli. Recombinant proteins were purified by metal affinity chromatography, and used as antigens in indirect ELISA. Serum samples from healthy and B. canis-infected humans and dogs were used to evaluate the performance of indirect ELISAs. Our results suggest that PdhB and Tuf proteins could be used as antigens for serologic detection of B. canis infection in humans, but not in dogs. The use of recombinant antigens in iELISA assays to detect B. canis-specific antibodies in human serum could be a valuable tool to improve diagnosis of human brucellosis caused by B. canis.

Common occurrence of Cryptosporidium hominis in children attending day-care centers in Medellin, Colombia.

Cryptosporidium spp. are apicomplexan protozoa associated with chronic diarrhea in AIDS and other immunocompromised patients, and one of the commonest causes of childhood diarrhea and malnutrition, particularly in low-income settings. In Colombia, there are few molecular epidemiological studies on Cryptosporidium spp.; thereby, the transmission dynamics of this parasite in the country is poorly known. This study evaluated the diversity of Cryptosporidium at species, subtype family, and subtype level in children attending various day-care centers in Medellin, Colombia. Two hundred and ninety stool samples from children < 5 years of age were collected from April to November of 2015. All samples were processed by PCR and sequence analysis of the ssu RNA gene and the gp60 gene. An infection rate of 2.4% was observed, with only two Cryptosporidium species identified: C. hominis (6/7) and C. meleagridis (1/7). Cryptosporidium hominis isolates belonged to the subtypes IbA10G2, IaA13R6 and IaA13R7; IIIbA26G1R1 C. meleagridis subtype was also detected. There is a C. hominis predominance in the children evaluated, suggesting an important role of the anthroponotic transmission cycle in the day-care centers analyzed. Further investigation is required to determine infection sources and susceptible hosts in order to define appropriate management of cryptosporidiosis.

Intestinal parasitic infection alters bacterial gut microbiota in children.

The study of the burden that parasites can exert upon the bacterial gut microbiota was restricted by the available technologies and their costs. Currently, next-generation sequencing coupled with traditional methodologies allows the study of eukaryotic parasites (protozoa and helminths) and its effects on the human bacterial gut microbiota diversity. This diversity can be altered by a variety of factors such as age, diet, genetics and parasitic infections among others. The disturbances of the gut microbiota have been associated with a variety of illnesses. Children population in developing countries, are especially susceptible to parasitic infections because of the lack of proper sanitation and undernutrition, allowing both, the thriving of intestinal parasites and profound alteration of the gut microbiota. In this work, we have sampled the stool of 23 children from four different children's care-centers in Medellin, Colombia, and we have identified the eukaryotic parasites by traditional and molecular methodologies coupled with microbial profiling using 16S rDNA sequencing. This mixed methodology approach has allowed us to establish an interesting relationship between Giardia intestinalis and helminth infection, having both effects upon the bacterial gut microbiota enterotypes, causing a switch from a type I to a type II enterotype upon infection.

Physiological and parasitological implications of living in a city: the case of the white-footed tamarin (Saguinus leucopus).

Among primates, the Neotropical Callitrichid monkeys (tamarins and marmosets) exhibit a particular ability to adapt to disturbed and urbanized environments. However, little is known about physiological and health status in contrasting ecological contexts. An example of adaptation to urban environments is the white-footed tamarin (Saguinus leucopus), an endangered species endemic to the central Andes in North West Colombia. This species was used as a model to contrast physical condition, physiological parameters and the parasite community of wild populations in rural and urban settings. Overall, the tamarins seemed to be in good body condition in both environments; however, urban tamarins exhibited overweight, elevated body mass, and higher cholesterol levels, while rural tamarins showed larger diversity and prevalence of parasites. Variation in several hematological parameters associated with altitude was also observed. Our data provide preliminary evidence of differential physiological responses to urban and rural environments in tamarins. These results may be attributed to nutritional factors, physical activity, and specific parasite-host ecological interactions in these two environments. Also, abundance and diversity of the parasite community in urban environments may be potentially constrained by habitat fragmentation and relatively fewer reservoirs. Finally, significant physiological and ecological disparities between white-footed tamarins occurring in urban and rural habitats as well as physiological response to hypoxia at higher altitudes were evidenced here. This study provides important preliminary information that will be useful to determine the ability of New World primate populations to cope with urban development and rapidly changing environments.

Transcriptome profiling of the cysticercus stage of the laboratory model Taenia crassiceps, strain ORF.

Neurocysticercosis (NC) is a serious public health problem mainly in developing countries. NC caused by the cysticercus stage from cestode Taenia solium is considered by the WHO and ITFDE as a potentially eradicable disease. Definitive diagnosis of NC is challenging because of the unspecific clinical manifestations such as the non-definitive evidence presented by neuroimaging (in most cases) and the lack of definitive serological test. Taenia crassiceps (ORF strain) is a cestode closely related to T. solium and it has frequently been used as a source of antigens for immunodiagnostics. A murine model to study host immune response to infection has also been established by using T. crassiceps. Despite the extensive use of T. crassiceps for research, molecular information for this cestode is scarce in public databases. With the aim of providing more extensive information on T. crassiceps biology, an RNA-seq experiment and subsequent bioinformatic transcriptome processing of this cestode parasite mRNA in its cysticercus stage were carried out. A total of 227,082 read/ESTs were sequenced using the 454-GS FLX Titanium technology and assembled into 10,787 contigs. This transcriptome dataset represents new and valuable molecular information of the cestode T. crassiceps (ORF). This information will substantially improve public information and will help to achieve a better understanding of the biology of T. crassiceps and to identify target proteins for serodiagnosis and vaccination.

Valoración clínica y parasitológica del tití gris (Primates: Cebidae: Saguinus leucopus) en dos poblaciones naturales presentes en San Carlos y San Rafael (Antioquia, Colombia) / Clinical and parasitological evaluation of White-footed Tamarins (Primates: Cebidae: Saguinusleucopus) from two free-range populations located in San Carlos and San Rafael (Antioquia, Colombia) / Valoração clínica e parasitológica do sagui cinza (Primates: Cebidae: Saguinus leucopus) em duas populações naturais que se encontram em San Carlos e San Rafael (Antioquia, Colômbia)

Resumen El estudio de individuos en cautiverio de primates Neotropicales ha permitido conocer aspectos básicos de su historia natural. Sin embargo las condiciones medioambientales pueden determinar diferencias ecológicas y fisiológicas en poblaciones silvestres. En el caso del tití gris (Saguinus leucopus), primate endémico del noroccidente colombiano, diferentes parámetros fisiológicos han sido evaluados en cautiverio. Con el fin de diagnosticar el estado de salud en condiciones naturales, se evaluaron varias características externas y parámetros fisiológicos, así como la comunidad de parásitos de dos poblaciones naturales. Aunque en general no se detectaron signos de deterioro en las condiciones generales de salud, se identificaron once taxones de parásitos entre helmintos y protozoos, algunos con alta prevalencia (filarias y Trypanosoma spp). Las comunidades de parásitos en cautiverio y en estado silvestre muestran diferencias notables. Igualmente, se identificó una aparente variación entre poblaciones silvestres e incluso entre grupos sociales circundantes con respecto a los perfiles hematológicos y de química sanguínea, que sugiere diferencias en la respuesta fisiológica ante condiciones medioambientales. Ninguna de dichas variables fisiológicas pareció estar relacionada con los parásitos encontrados. Los resultados revelaron una amplia diversidad de parásitos y una elevada tasa de infecciones parasitarias en poblaciones naturales de S. leucopus, que parecen no estar asociadas con indicadores de la condición de salud. Futuros estudios deberán enfatizar en aspectos ecológicos, genéticos y demográficos que determinen las condiciones de salud de S. leucopus en su medio natural. Se recomienda que la rehabilitación de individuos en cautiverio tenga presente posibles diferencias en variables fisiológicas y epidemiológicas entre poblaciones naturales y grupos en cautiverio con el fin de restringir la transmisión de agentes infecciosos entre ...

Abstract While much of the natural history of Neotropical primates has been revealed through studies conducted in captive individuals, environmental factors may impose ecological and physiological differences in free-range populations. For the white-footed tamarin (Saguinus leucopus), a primate endemic to Northwest Colombia, physiological parameters that have been assessed in captivity still remain to be measured in free-range populations. In order to diagnose the health status of this species in a natural environment, we assessed several external traits, measured hematological and blood-chemistry values, and characterized the parasite community of two natural populations. Despite the identification of eleven different parasite taxa and wide distribution of filaria and Trypanosoma spp., we faieled to detect signs of poor health condition. Substantial differences were found between captive and free-range tamarin populations in the composition of their parasite communities. Likewise, hematological and blood-chemistry profiles differed between free-range populations and even between neighboring social groups, suggesting a role of environmental factors in the physiological response. However, none of the physiological parameters varied as a response to parasite infection. Our results revealed a high diversity of parasites and elevated rates of parasitic infections in natural populations of S. leucopus, that do not seem to be associated with indicators of health conditions. Future studies should emphasize on ecological, genetic and demographic factors that determine the health conditions of S. leucopus in the wild. Lastly, geographic variation of physiological profiles and parasite distribution, as well as epidemiological differences between captive and wild populations, should be incorporated in rehabilitation plans of captive tamarins in order to restrict the transmission of infectious agents between populations.

Resumo O estudo de indivíduos em cativeiro de primatas Neotropicais tem permitido conhecer aspectos básicos da história natural. Embora as condições ambientais podem determinar diferenças ecológicas e fisiológicas em populações silvestres. No caso do sagui cinza (Saguinus leucopus), primata endémico do noroeste colombiano, diferentes parâmetros fisiológicos tem sido avaliados em cativeiro. Com o intuito de diagnosticar o estado de saúde em condições naturais, avaliaram-se vários rasgos externos e parâmetros fisiológicos, assim como a comunidade de parasitas de duas populações naturais. Ainda que em geral não se detectassem signos de deterioro nas condições gerais de saúde, identificaram-se onze táxones de parasitas entre helmintos e protozoários, alguns com alta prevalência (filarias e Trypanosoma spp). As comunidades de parasitas em cativeiro e no estado silvestre mostram diferenças notáveis. Igualmente, identificou-se uma aparente variação entre populações silvestres e entre grupos sociais circundantes com respeito aos perfis hematológicos e de química sanguínea, que sugere diferenças na resposta fisiológica diante condições ambientais do médio. Nenhuma das mencionadas variáveis fisiológicas pareceu estar relacionada com as parasitas encontradas. Os resultados revelaram uma grande diversidade de parasitas e uma alta taxa de infecção parasitária em populações naturais de S. leucopus, que não parecem estar associados com indicadores do condição de saúde. Estudos deste tipo no futuro deveram enfatizar em aspectos ecológicos, genéticos e demográficos que determinem as condições de saúde de S. leucopus em seu médio natural. Recomenda-se que a reabilitação de indivíduos em cativeiro tenha presente possíveis diferenças em variáveis fisiológicas e epidemiológicas entre populações naturais e grupos em cativeiro com o fim de restringir a transmissão de agentes infeciosos entre populações.

Paragonimiasis pulmonar en niños: reporte de dos casos / Lung paragonimiais in children: Report of two cases

La paragonimiasis es una zoonosis parasitaria, de transmisión alimentaria, causada por especies de tremátodos del género Paragonimus, presente en áreas tropicales y subtropicales de Asia, África y América. El ser humano se infecta mediante la ingestión de crustáceos de agua dulce crudos o mal cocidos. La infección afecta principalmente los pulmones, con desarrollo de múltiples manifestaciones clínicas y radiológicas, dependiendo del momento del ciclo vital del parásito. El diagnóstico diferencial más importante de esta enfermedad es la tuberculosis pulmonar. En este artículo se describe esta enfermedad en dos niñas con diferentes manifestaciones pulmonares. La paragonimiasis se debe sospechar en pacientes con tos crónica, esputo herrumbroso, dolor torácico, con o sin compromiso cerebral, que viven o han residido en una zona endémica y que presentan una eosinofília elevada, con cambios radiológicos sugestivos del síndrome de Loeffler.

Paragonimiasis is a parasitic, food-borne zoonosis, caused by species of trematodes of the genus Paragonimus, found in tropical and subtropical areas of Asia, Africa and America. Human beings become infected by ingestion of raw or undercooked freshwater shellfish. The infection primarily affects the lungs, with the development of multiple clinical and radiological manifestations, depending on the moment in the life cycle of the parasite. The most important differential diagnosis of this disease is pulmonary tuberculosis. We report two cases of lung paragonimiasis in aboriginal Colombian girls with different pulmonary manifestations. Paragonimiasis should be suspected in patients with chronic cough, rusty sputum, chest pain, with or without brain involvement, who live or have lived in endemic areas and have a high-level eosinophilia with radiographic changes suggestive of Loeffler's syndrome.

Prevalencia de parásitos intestinales en niños que asisten al Templo Comedor Sagrado Corazón Teresa Benedicta de la Cruz, del barrio Vallejuelos, Medellín, 2007 / Intestinal parasites prevalence in children from "Templo-Comedor Sagrado Corazón Teresa Benedicta de la Cruz",Vallejuelos-Medellín, 2007.

Introducción: los seres humanos estamos expuestos a los parásitos presentes en el medio en quehabitamos, lo que puede plantear un problema de salud pública, especialmente en los países en vías de desarrollo como Colombia. La población más vulnerable es la infantil, especialmente la de comunidades en condiciones socioeconómicas precarias.Objetivo: determinar la prevalencia de parásitos intestinales en los niños que acuden a un templocomedor en un barrio marginal de Medellín.Métodos: en octubre y noviembre de 2007 se hizo un estudio descriptivo transversal, mediante un coprológico directo y por concentración, en 58 de los 150 niños que acuden al templo-comedor; lo anterior se complementó con una encuesta sobre algunas variables sociodemográficas.Resultados: se halló que 54 de los 58 niños (93%) estaban parasitados y que en 48 de ellos (88,9%) losparásitos eran potencialmente patógenos; entre estos predominó Entamoeba histolytica/dispar(46,6%), seguida por Giardia intestinalis (25,9%), Trichuris trichiura (25,9%), Ascaris lumbricoides (24,1%) y Enterobius vermicularis (8,6%). Se halló multiparasitismo en 21 niños (38,8%). En cuanto a la relación entre algunas variables sociodemográficas y la frecuencia de parásitos solo se halló que el hacinamiento en la vivienda se asociaba significativamente con la presencia de Entamoeba histolytica/dispar y de Blastocystis hominis, y la tenencia de mascotas, con la infección por Enterobiusvermicularis.Conclusión: la prevalencia de parasitosis intestinales hallada en este trabajo superó la de otros grupos tanto colombianos como extranjeros. Se discuten las implicaciones de este hallazgo desde el punto de vista de la salud pública.

Introduction: Human beings are exposed to the parasites present in their habitat. This situation poses a public health problem, especially in underdeveloped countries such as Colombia. The pediatric population is the most vulnerable, particularly that of communities in poor socioeconomic conditions.Objective: To determine the prevalence of intestinal parasites in children attending a social aid institution in a poor neighborhood of Medellín, Colombia.Methods: In October and November 2007 a descriptive cross-sectional study was carried out by means of direct and concentration stool examination in 58 out of 150children attending the aforementioned institution. In addition, a survey was made of some socio-demographicvariables.Results: 54 of the 58 children (93%) were infected by intestinal parasites. In 48 of them (88.9%) potentiallypathogen parasites were present, namely: Entamoeba histolytica/dispar (46.6%), Giardia intestinalis (25.9%), Trichuris trichiura (25.9%), Ascaris lumbricoides (24.1%), and Enterobius vermicularis (8.6%). Twenty one children (38.8%) were infected with either 2 or 3 parasites. The only significant associations between socio demographic variables and parasitic infections were as follows:overcrowding was associated with Entamoeba histolytica/dispar and Blastocystis hominis, and thepresence of pets (mostly dogs) in the house was associated with Enterobius vermicularis.Conclusion: Prevalence rate of intestinal parasites was higher in the studied group than in other communities, both Colombian and from other countries. Implicationsof this finding from the public health perspective are discussed.

Giardia intestinalis and nutritional status in children participating in the complementary nutrition program, Antioquia, Colombia, May to October 2006.

Giardia intestinalis infection is prevalent throughout the world and widely distributed in developing countries. In general, children display serious consequences to their state of health, including slow height-weight development; therefore, the main aim of this study was to determine the association between Giardia infection and the nutritional status of children who participate in the program of complementary feeding (Mejoramiento Alimentario y Nutricional de Antioquia (MANA) - Instituto Colombiano de Bienestar Familiar (ICBF)). A cross-sectional study examining the association of giardiasis with nutritional status was conducted. A total of 2035 children aged eight months to six years-old were studied. Data were collected using structured questionnaires, anthropometric measurements and laboratory analysis of blood and stool samples. Analysis of the results showed that 27.6% of children were infected with G. intestinalis, while 8.1% and 1.9% were mildly and significantly underweight, respectively, and 14.1% presented stunting. Giardiasis was statistically identified as a strong predictor of stunting in this study population.

Giardia intestinalis and nutritional status in children participating in the complementary nutrition program, Antioquia, Colombia, May to October 2006 / Giardia intestinalis e estado nutricional em crianças participantes do programa de nutrição complementar, melhoramento alimentar e nutricional da Antioquia (MANA): Instituto Colombiano de Bem-Estar Familiar (ICBF), Antióquia, Colombia, maio a outubro de 2006

Giardia intestinalis infection is prevalent throughout the world and widely distributed in developing countries. In general, children display serious consequences to their state of health, including slow height-weight development; therefore, the main aim of this study was to determine the association between Giardia infection and the nutritional status of children who participate in the program of complementary feeding (Mejoramiento Alimentario y Nutricional de Antioquia (MANA) - Instituto Colombiano de Bienestar Familiar (ICBF)). A cross-sectional study examining the association of giardiasis with nutritional status was conducted. A total of 2035 children aged eight months to six years-old were studied. Data were collected using structured questionnaires, anthropometric measurements and laboratory analysis of blood and stool samples. Analysis of the results showed that 27.6% of children were infected with G. intestinalis, while 8.1% and 1.9% were mildly and significantly underweight, respectively, and 14.1% presented stunting. Giardiasis was statistically identified as a strong predictor of stunting in this study population.

A infecção pela Giardia intestinalis está amplamente distribuída no mundo apresentando a maior prevalência nos países em desenvolvimento. Em crianças, esta parasitose pode ter conseqüências graves no estado geral de saúde assim como no ganho de peso e estatura. O objetivo desta pesquisa foi estabelecer a associação entre a infecção com Giardia e o estado nutricional das crianças beneficiárias do programa de complementação alimentar - MANA. Um estudo de corte no qual foram avaliadas 2035 crianças entre os oito meses e os seis anos de idade foi realizado. A informação foi obtida a partir de questionários estruturados, medições antropométricas e exame de fezes. Os resultados mostraram que 27,6% das crianças estavam infectadas com Giardia intestinalis, das quais 8,1% apresentaram desnutrição moderada, 1,9% desnutrição grave e 14,1% franca queda no crescimento. Em conclusão, nesta população a Giardíase foi indicador de desnutrição grave.