Cyclospora cayetanensis: biología, distribución ambiental y transferencia

Cyclospora cayetanensis is an apicomplexan protozoan that has emerged as an important pathogen causing endemic or epidemic diarrheal disease worldwide. In industrialized countries, the parasite has been recognized as the causative agent of several outbreaks of diarrheal illness mostly associated with produce imported from endemic areas. In developing countries, human cyclosporosis is widely distributed. Infection rates from 0% to 41.6% have been described in the general population. However, the epidemiology, biology, and ecology of C. cayetanensis are not fully understood. The life cycle is not completely characterized, although it appears to require a single human host to be accomplished. The role of animals as natural reservoirs of the parasite remains to be determined.Little information is available concerning the environmental distribution and vehicles of transmission of C. cayetanensis. Contaminated water, foods or soil can be vehicles of spread of the parasite. The significant uncertainties that remain in the knowledge of C. cayetanensis highlight the need for continuing research in several areas, including its basic biology and environmental distribution.Cyclospora cayetanensis es un protozoo apicomplexa que ha emergido como un patógeno importante causante de diarrea endémica y epidémica en el mundo. En los países industrializados, el parásito se ha reconocido como agente causal de diversas epidemias asociadas, principalmente, con alimentos importados de áreas endémicas. En los países en vías de desarrollo, la ciclosporosis humana está ampliamente distribuida y, en la población general, se han descrito tasas de infección que varían de 0 % a 41,6 %. Sin embargo, la epidemiologia, biología y ecología de C. cayetanensis permanecen poco conocidas. Su ciclo de vida no está totalmente caracterizado y parece requerir un huésped único, el humano, para completarse. El papel que los animales puedan desempeñar como reservorios naturales del parásito permanece sin determinar.Se tiene poca información sobre la distribución ambiental de C. cayetanensis y los vehículos de transmisión del ambiente a los humanos. El agua, los alimentos y los suelos contaminados pueden actuar como vehículos de diseminación del coccidio. Permanecen incertidumbres significativas sobre el parásito, que reflejan la necesidad de continuar los esfuerzos de investigación en diversas áreas, incluyendo su biología básica y distribución ambiental

Infecção pelo vírus da Hepatite C em pacientes em hemodiálise em Maracaibo, Venezuela

Over a two year period, the incidence of hepatitis C virus (HCV) infection was evaluated in 29 hemodialysis patients, aged between 15 and 75 years (mean ± SD: 45 ± 39.5 years), from the University Hospital Hemodyalisis Unit, Maracaibo, Zulia State, Venezuela. Anti-HCV antibodies were determined using a fourth generation ELISA (Innotest HCV Ab IV) kit and positive blood samples were tested using a recombinant assay kit (Inno-LIA HCV Ab III), both kits from Innogenetics N.V., Belgium. The findings indicate a lack of HCV seroconversion in the hemodialysis patients over the study period, confirmed by the recombinant assay. Risk factors for HCV infection were 0.3270 (95% confidence interval: 0.01323-8.080) in patients undergoing hemodialysis. The findings suggest a lack of significant sources for HCV infection due to the preventive measures to avoid its transmission in the hemodialysis unit.Durante período de 2 anos, estudamos a incidência da infecção pelo vírus da hepatite C (VHC) em 29 pacientes em tratamento de diálise, com idades entre 15 e 75 anos (c ± DS; 45 ± 39,5 anos), procedentes da unidade de hemodiálise do Hospital Universitário de Maracaibo, Estado Zulia, Venezuela. Para a detecção dos anticorpos contra o VHC (anti-VHC) utilizamos a técnica de imunoensaio enzimático (ELISA, Innotest HCV Ab IV) e em amostras reativas por ELISA, utilizamos o método de immunoblot recombinante de terceira geração (Inno-LIA HCV Ab III), ambos da casa comercial Innogenetics N.V., Bélgica. Os resultados demonstram ausência de soroconversão ao VHC nos pacientes hemodializados durante o período estudado, o que foi confirmado pelo método de imunoblot recombinante. Os fatores de risco ao VHC foram 0,327 (95% CI: 0,01323 - 8,080) nos pacientes submetidos ao tratamento de diálise. Nossos resultados sugerem ausência de fontes de infecção neste centro de hemodiálise e que as medidas universais de controle de infecção são cumpridas

Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis

Background: Globally cryptosporidiosis is one of the commonest causes of mortality in children under 24 months old and may be associated with important longterm health effects. Whilst most strains of Cryptosporidium parvum are zoonotic, C. parvum IIc is almost certainly anthroponotic. The global distribution of this potentially important emerging infection is not clear. Methods: We conducted a systematic review of papers identifying the subtype distribution of C. parvum infections globally. We searched PubMed and Scopus using the following key terms Cryptospor* AND parvum AND (genotyp* OR subtyp* OR gp60). Studies were eligible for inclusion if they had found C. parvum within their human study population and had subtyped some or all of these samples using standard gp60 subtyping. Pooled analyses of the proportion of strains being of the IIc subtype were determined using StatsDirect. Meta-regression analyses were run to determine any association between the relative prevalence of IIc and Gross Domestic Product, proportion of the population with access to improved drinking water and improved sanitation. Results: From an initial 843 studies, 85 were included in further analysis. Cryptosporidium parvum IIc was found in 43 of these 85 studies. Across all studies the pooled estimate of relative prevalence of IIc was 19.0% (95% CI: 12.9–25.9%), but there was substantial heterogeneity. In a meta-regression analysis, the relative proportion of all C. parvum infections being IIc decreased as the percentage of the population with access to improved sanitation increased and was some 3.4 times higher in those studies focussing on HIV-positive indivduals. Conclusions: The anthroponotic C. parvum IIc predominates primarily in lower-income countries with poor sanitation and in HIV-positive individuals. Given the apparent enhanced post-infectious virulence of the other main anthroponotic species of Cryptosporidium (C. hominis), it is important to learn about the impact of this subtype on human health

Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis

Background: Globally cryptosporidiosis is one of the commonest causes of mortality in children under 24 months old and may be associated with important longterm health effects. Whilst most strains of Cryptosporidium parvum are zoonotic, C. parvum IIc is almost certainly anthroponotic. The global distribution of this potentially important emerging infection is not clear. Methods: We conducted a systematic review of papers identifying the subtype distribution of C. parvum infections globally. We searched PubMed and Scopus using the following key terms Cryptospor* AND parvum AND (genotyp* OR subtyp* OR gp60). Studies were eligible for inclusion if they had found C. parvum within their human study population and had subtyped some or all of these samples using standard gp60 subtyping. Pooled analyses of the proportion of strains being of the IIc subtype were determined using StatsDirect. Meta-regression analyses were run to determine any association between the relative prevalence of IIc and Gross Domestic Product, proportion of the population with access to improved drinking water and improved sanitation. Results: From an initial 843 studies, 85 were included in further analysis. Cryptosporidium parvum IIc was found in 43 of these 85 studies. Across all studies the pooled estimate of relative prevalence of IIc was 19.0% (95% CI: 12.9–25.9%), but there was substantial heterogeneity. In a meta-regression analysis, the relative proportion of all C. parvum infections being IIc decreased as the percentage of the population with access to improved sanitation increased and was some 3.4 times higher in those studies focussing on HIV-positive indivduals. Conclusions: The anthroponotic C. parvum IIc predominates primarily in lower-income countries with poor sanitation and in HIV-positive individuals. Given the apparent enhanced post-infectious virulence of the other main anthroponotic species of Cryptosporidium (C. hominis), it is important to learn about the impact of this subtype on human health

Gestión del conocimiento: perspectiva multidisciplinaria. Volumen 13

El libro “Gestión del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 13 de la Colección Unión Global, es resultado de investigaciones. Los capítulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro es una publicación internacional, seriada, continua, arbitrada, de acceso abierto a todas las áreas del conocimiento, orientada a contribuir con procesos de gestión del conocimiento científico, tecnológico y humanístico. Con esta colección, se aspira contribuir con el cultivo, la comprensión, la recopilación y la apropiación social del conocimiento en cuanto a patrimonio intangible de la humanidad, con el propósito de hacer aportes con la transformación de las relaciones socioculturales que sustentan la construcción social de los saberes y su reconocimiento como bien público. El libro “Gestión del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 13, de la Colección Unión Global, es resultado de investigaciones. Los capítulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro cuenta con el apoyo de los grupos de investigación: Universidad Sur del Lago “Jesús María Semprúm” (UNESUR) - Zulia – Venezuela; Universidad Politécnica Territorial de Falcón Alonso Gamero (UPTFAG) - Falcón – Venezuela; Universidad Politécnica Territorial de Mérida Kléber Ramírez (UPTM) - Mérida - Venezuela; Universidad Guanajuato (UG) - Campus Celaya - Salvatierra - Cuerpo Académico de Biodesarrollo y Bioeconomía en las Organizaciones y Políticas Públicas (CABBOPP) - Guanajuato – México; Centro de Altos Estudios de Venezuela (CEALEVE) - Zulia – Venezuela, Centro Integral de Formación Educativa Especializada del Sur (CIFE - SUR) - Zulia – Venezuela; Centro de Investigaciones Internacionales SAS (CEDINTER) - Antioquia – Colombia y diferentes grupos de investigación del ámbito nacional e internacional que hoy se unen para estrechar vínculos investigativos, para que sus aportes científicos formen parte de los libros que se publiquen en formatos digital e impreso