[Chagas disease: re-emergent or neglected]. / Enfermedad de Chagas: reemergente o desasistida.

Chagas disease is a tropical parasitic disease distributed throughout America, from southern United States to Argentina, mostly, in poor and rural areas of Central and South America. According to the latest estimates, there are 8 million people all over the world infected by the parasite and in 2008, 11000 deaths were registered. Currently, with the occurrence of internal migrations from rural areas to cities, the disease is changing the establishment of its epidemiological profile. Instead of an effective control or eradication, as consequences of the antichagasic campaign initiated in Venezuela 47 years ago, as many cases are emerging today, in some westerns states of the country, as those reported at the beginning of the last century. In addition, there is a considerable increase in the oral transmission of the disease, through neglect and the lack of sanitary controls in food processing. For these reasons, a monitoring system of rapid response must be implemented by the Venezuelan health system to control the disease.

[Human fasciolosis in Mara municipality, Zulia state. Venezuela: prevalence and asociated factors]. / Fasciolosis humana en el municipio Mara, estado Zulia, Venezuela: prevalencia y factores asociados.

In Venezuela, human Fasciolosis shows a low frequency. However, Mara Municipality is a highly endemic region for bovine fasciolosis and there are no reports of this parasite infection in humans. To determine the prevalence and associated factors to human fasciolosis in Mara municipality - Zulia state, a total of 51 blood and stool samples were collected. Serums were tested by ELISA and Western Blot (WB) assays, with excretion-secretion antigens of Fasciola hepatica (AFhES). The serum samples that resulted positive by these assays were tested by ELISA IgG anti Toxocara sp, Toxoplasma gondii and cysticerosis. Stool samples were concentrated by the Ritchie and rapid sedimentation techniques. Two serum samples were reactive to ELISA AFhES (3.9%) and these did not recognize the specific molecules of WB-AFhES detected by serum from patients with an absolutely demonstrated infection. Both participants were not positive to IgG anti Toxocara sp, Toxoplasma gondii, cysticerosis, and stool samples of these were negative to intestinal parasites. The general prevalence of intestinal parasites was 52.9% (27/51), being protozoa more frequent than helminthes. No Fasciola eggs were found. The two positives participants had in common that both had worked as fresh pasture cutters. These results suggest that the population had been in contact with F. hepatica, with no active infection because of the lack of specific molecules recognition and the absence of eggs in stool samples. Human fasciolosis has a low frequency in Venezuela and is underestimated and underrecognized by health workers and the general population.

[Amebiasis: importance of the diagnosis and treatment. Minireview]. / Amibiasis: importancia de su diagnóstico y tratamiento. Mini-revisión.

The protozoa E. histolytica is the etiologic agent of human amebiasis, the identification of its pathogenicity has been of great aid in the search of important antigens for immunodiagnostic and inmunoprofilaxis. In 1995 the isolation and axenization of the first two strains of Venezuelan E. histolytica were described from symptomatic patients, which were denominated: IULA 1092:1 and IULA: 0593:2 These strains have been evaluated through studies of electrophoretic profiles, demonstrating the presence of type II zymodemes, characteristic of pathogenic strains. Also, they have shown to be of high virulence, they present a complex pattern of reactivity and the presence of a marker antigen of pathogenicity. The isoenzymatic analysis has shown correlation with the genotypic analysis, showing a genotypic organization typical of a pathogenic strain. With this strain, it has been possible to evaluate all the amebiasis cases sent to the Institute of Clinical Immunology of Universidad de Los Andes, in Merida, Venezuela. These strains have been useful, here, as well as in other sites, when using their antigens to evaluate urban and even indigenous populations. They can be used, like native strains of reference, in diagnostic tests and prophylaxis for this parasitosis. The limitations of the microscopic analysis, specifically, the false amebiasis diagnosis and its inability to discriminate between infections caused by E. histolytica and E. dispar have led to the development of laboratory procedures that allow for the detection of components of the species present. The success of such procedures would result in a diminution of unnecessary treatments, which could be the cause of antiamoebic drug resistance.

[Serologic diagnostic of Toxoplasma gondii infections]. / Diagnóstico serológico de las infecciones por Toxoplasma gondii.

The diagnostic of T. gondii infection is one of the most interesting features of the disease for investigators, since parasitological diagnostic is difficult to reach in the early period of the infection. The diagnostic is exclusively based in the detection of serum specific antibodies (IgG, IgM, IgA, IgE) and more recently, in the avidity of serum IgG. No matter the high specificity and sensitivity of the test used for diagnostic, one test sample is not enough to inform us about the antibody type as a parameter for early or late period of infection.

[Prevalence of giardiasis in day care centers in San Francisco municipality, state of Zulia, Venezuela]. / Prevalencia de Giardiasis en Hogares de Cuidado Diario en el municipio San Francisco, estado Zulia, Venezuela.

The number of children Day Care Centers has increased progressively in underdeveloped countries. These Institutions offer conditions that facilitate the transmission of enteric agents. The aim of the present study was to determine the prevalence of Giardiasis in Day Care Centers from San Francisco municipality, Zulia state, Venezuela. A poll was applied to collect personal and clinical data. Fecal samples from 82 children of one or another sex, between 11 months and 6 years old, who normally assist to four Day Care Centers of the municipality mentioned above, were analyzed. The samples were processed by fresh examination, lugol temporal coloration and the formol-ether technique. A percentual analysis was applied for the statistical study. From the 82 processed samples, 37 (45.1%) showed the presence of Giardia lamblia. The clinical symptoms most frequently observed in the study were abdominal pain, diarrhea, weight loss and inappetence. Statistical results did not show a significant difference of this parasitic disease with relationship to sex; however, there is a predominance in children of school age (75%). The result of this work shows a high prevalence of Giardiasis in Day Care Centers of the municipality studied, which suggests that this institutions gather the conditions that facilitate the transmission of this flagellate, and that preventive measures must be put into practice.

[Prevalence of infection by Toxocara in schoolchildren in the community of El Moján, Zulia state, Venezuela]. / Prevalencia de infección por Toxocara en pre-escolares de una comunidad educativa de El Moján, estado Zulia, Venezuela. Resultados preliminares.

The systemic Toxocariasis or migrant larva is a helminto-zoonosis caused by the migration of nematode larvae through human tissues mainly, of the canine helminth Toxocara canis, which can infect humans, especially children. The aim of this study was to determine the prevalence of anti-T. canis antibodies in an infantile population. Serum samples of 73 children of either sex with ages between 4 and 6 years were examined. The determination of anti-Toxocara antibodies was carried out through an ELISA test (using excretory/secretory antigen from the Toxocara larvae). The statistical analysis was carried out through the Chi square test, the Fisher exact test and the correlation of Spearman. The overall prevalence of infection was 9.72%, the highest percentage (50%) was observed in 4 year-old children (3/6), there were significant differences among the ages. No differences were observed with regard to sex. An inverse correlation was observed between the age and ELISA positivity. These results suggest that the toxocariasis is frequent in children from this community.

Seroprevalencia y factores de riesgo asociados a infección por Trypanosoma cruzi y Toxoplasma gondii en la comunidad Saimadoyi, Sierra de Perijá, estado Zulia / Seroprevalence and risk factors associated to infection by Trypanosoma cruzi and Toxoplasma gondii in the Saimadoyi community, Sierra de Perija, Zulia state

La enfermedad de Chagas y la toxoplasmosis constituyen problemas de salud característicos de zonas rurales. El objetivo de esta investigación fue determinar la seroprevalencia de Trypanosoma cruzi y Toxoplasma gondii en la comunidad Saimadoyi. Se estudiaron 166 muestras de sueros de individuos de ambos sexos (100 femeninos y 66 masculinos) con edades comprendidas entre 1 a 83 años. La determinación de anticuerpos se realizó a través de la técnica de ELISA, utilizando kits disponibles comercialmente. La seroprevalencia de Trypanosomacruzi fue de 51% (87/166), mientras que para Toxoplasma gondii fue de 57% (95/166). La mayoría de casos positivos se encontraron en los individuos menores de 20 años, sin embargo, no se encontraron diferencias significativas con respecto al género o grupo de edad para ambas parasitosis. Los datos epidemiológicos mostraron que los factores de riesgo estadísticamente significativos (p<0,05) para la infección por T. cruzi fueron el tipo de vivienda, contacto con perros o chipos y contaminación del suelo con heces; mientras que para la infección por T. gondii, el contacto con gatos y la higiene inadecuada fueron los riesgos significativos. El elevado número de casos seropositivos en mujeres en edad reproductiva sugiere la transmisión vertical de ambos parásitos.

Chagas disease and toxoplasmosis are health problems characteristic of rural areas. The aim of this research was to determine the seroprevalence of Trypanosoma cruzi y Toxoplasma gondii. in community Saimadoyi. 166 serum samples from individuals of both sexes (100 female 66 male and) aged 1-83 years were studied. The determination of antibodies was performed by ELISA using a commercial kit. Trypanosoma cruzi seroprevalence was 51% (87/166), while for Toxoplasma gondii was 57% (95/166). Most positive cases were found in people under 20 years old, however no significant differences with regard to gender or age group for both parasites were found. Epidemiological data showed statistically significant risk factors (p <0.05) for T. cruzi infection were the type of housing, contact with dogs or chipos and soil contamination with feces; while for T. gondii infection, contact with cats and poor hygiene were the significant risks. The high number of seropositives cases in women of reproductive age suggests vertical transmission of both parasites.

Enteroparásitos en niños de una comunidad indígena del municipio Machiques de Perijá, estado Zulia Venezuela / Enteroparasites in children of an indigenous community in Machiques de Perijá, Zulia state Venezuela

Con la finalidad de determinar la prevalencia de enteroparásitos en niños de una comunidad indígena del municipio Machiques de Perijá del estado Zulia, fueron analizadas 139 muestras fecales provenientes de niños en edades comprendidas entre 0 a 12 años de edad. A cada espécimen fecal se le realizó un examen coproparasitológico al fresco con solución salina fisiológica al 0,85% y coloraciones temporales NAIR y lugol, así como la técnica de concentración de Ritchie. Se observó una prevalencia general de niños parasitados de 87,7 % No hubo diferencia significativa en cuanto al estudio de las variables parasitosis y sexo. Se observó un predomino del poliparasitismo (68, 35%) sobre el monoparasitismo (20,15%). En cuanto al grupo de edades, el estrato de 2 a 6 años resultó el mayormente parasitado (43,92 %). El χ2 reveló que si existe relación significativa entre las variables parasitismo y edad. Las especies parasitarias que obtuvieron una mayor prevalencia fueron: Entamoeba coli (46,06%), Blastocystis sp. (43,16%), Trichuris trichiura (30,94%) y Ascaris lumbricoides (21,58%), en todo el grupo estudiado. Estos resultados son similares a los obtenidos en investigaciones previas. La alta prevalencia de protozoarios sugieren un patrón de transmisión directa entre la población estudiada o a través del consumo de agua y/o alimentos contaminados fecalmente.

In order to determine the prevalence of intestinal parasites in children from an indigenous community in the municipality Machiques de Perija of Zulia state, they were analyzed fecal samples from 139 children aged between 0-12 years old. Each stool specimen was conducted a coproparasitological fresh examination with physiological saline 0.85% and temporary colorations NAIR and lugol, as well, Ritchie´s concentration technique. An overall prevalence of children parasitized 87.7% was observed, no significant differences in the studies of the variables parasitosis and sex. It was observed a predomine of polyparasitism (68,35%) on monoparasitism (20,15%). As for the age group, stratum 2 to 6 years was the mostly parasitized (43.92%). The X² revealed that if there is significant relationship between variables and age parasitism. Parasitic species obtained a higher prevalence were: Entamoeba coli (46.06%), Blastocystis sp. (43.16%), Trichuris trichiura (30.94%) and Ascaris lumbricoides (21.58%) throughout the study group. These results are similar to those obtained in previous research. The high prevalence of protozoan suggest a pattern of direct transmission between the study population or through consumption of water and/or fecally contaminated food.

Inmunidad anti-cisticerco en una comunidad indígena del occidente venezolano / Anti-Cysticercus Immunity in an Amerindian Community from Western Venezuela

Para determinar la presencia de anticuerpos anti-cisticerco en una comunidad indígena del occidente venezolano, 93 individuos entre 1-78 años de edad fueron estudiados. La detección de anticuerpos anti cisticerco se realizó mediante la técnica inmunoenzimática de ELISA con extractos antigénicos de fluido vesicular de Taenia crassiceps. Los sueros fueron considerados positivos a diluciones ≥ 1:256 y las heces fueron estudiadas mediante examen parasitológico directo y concentrado. El 27,9% de la población presentó inmunidad anti-cisticerco y todos los grupos etarios fueron positivos. No se observaron diferencias estadísticamente significativas en relación al sexo, ni entre los grupos etarios. En el examen físico y en la historia clínica, no se encontraron datos relevantes de una probable alteración funcional en relación a cisticercosis. El porcentaje general de infección parasitaria fue de un 81,5%, con un marcado poliparasitismo de un 64,6%, con predominio de infección por protozoarios. No se detectaron huevos de Taenia spp. Este es el primer estudio sobre la prevalencia de anticuerpos anti-cisticerco en una comunidad indígena del occidente venezolano, con un alto porcentaje de la prevalencia desde la infancia, sugiriendo una exposición temprana a la cisticercosis. Además, una alta prevalencia de protozoarios y helmintos intestinales, lo que supone un riesgo sanitario considerable en esta población.

To determine the presence of anti-cysticercus antibodies in an Amerindian community in western Venezuela, ninety-three individuals between 1-78 years of age were studied. Anti-cysticercus antibodies were detected using the ELISA immune-enzymatic technique with antigenic extracts of vesicular fluid of Taenia crassiceps. Sera were considered positive at 1:256 dilutions; feces were studied by direct and concentrate parasitological examination. A 27.9% of the population had anti-cysticercus immunity, and all age groups were positives. No statistically significant differences in relation to sex or between age groups were observed. In the physical examination and medical history, no data relevant to a probable functional impairment related to cysticercosis were found. The overall percentage of parasitic infection was 81.5%, with a marked polyparasitism of 64.6% and a predominance of protozoan infection. No Taenia spp eggs were detected. This is the first study on the prevalence of anti-cysticercus antibodies in an indigenous community of western Venezuela with a high percentage of prevalence from childhood, suggesting early exposure to cysticercosis. In addition, a high prevalence of intestinal protozoa and helminthes were found, which supposes a significant health risk in this population.

Seroepidemiology of toxoplasmosis in women of childbearing age from a marginal community of Maracaibo, Venezuela.

The aim of this study was to determine the prevalence of anti-T. gondii total and IgM antibodies in women of childbearing age. One hundred serum samples of women were studied with age range from 11 to 45 years old. Samples were chosen by random. The determination of total antibodies was carried out through the indirect hemagglutination technique and IgM antibodies by ELISA's technique. The statistical analysis was carried out through the Chi square and the Spearman correlation tests. The theoretical estimated incidence of congenital toxoplasmosis was calculated, according to the annual increment of antibody prevalence among the age groups. The overall prevalence of toxoplasmosis was 33%, while only six individuals (18.2%) were positive to IgM. The highest prevalence was observed in the 11-35 year-old age group. The theoretical estimated incidence was 1.5 for 100 pregnancies in women of 21-25 year-old group; it decreased until 0.1% in the 41-45 year-old age group. The findings show a high prevalence of toxoplasmosis in this community with a high infection risk in women of the studied age group and the high cat population observed, suggesting that the transmission way by contaminated soils may play a main role in the spreading of toxoplasmosis in this community.

Detección de protozoos parásitos entéricos, bacteriófagos de E. coli y organismos indicadores de contaminación en camarones comercializados en el estado Zulia / Detection of enteric protozoa parasites, E. coli bacteriophages and fecal pollution Indicator organisms in shrimp sold in the state of Zulia

Se determinó la presencia de Giardia intestinalis y Cryptospodidium parvum, bacteriófagos de Escherichia coli y organismos indicadores de contaminación (OIC), en muestras de camarones para el consumo humano comercializados en el estado Zulia. Los parásitos se concentraron a partir de sistemas digestivos de pools de camarones por la técnica de formol-éter y se cuantificaron por inmunofluorescencia directa. La concentración de los bacteriófagos de E. coli F+ y los OIC se evaluó por técnicas estándar. En este trabajo se detectó la presencia de G. intestinalis, C. parvum, bacteriófagos y E. coli en camarones comercializados en el estado Zulia que cumplían los criterios de la normativa venezolana de calidad sanitaria e inocuidad. Del total de muestras analizadas el 91,5% fueron positivas para G. intestinalis (promedio: 36,6 quistes/100g), 95,3% para C. parvum (promedio: 32,8 ooquistes/100g), 100% para los bacteriófagos de E coli F+ (promedio de 2,8 x 103 UFP/100 g) y 71,5% para E. coli (promedio de 4,3 x 104 NMP/g). Los resultados obtenidos indican que los camarones pueden convertirse en un vehículo para la transmisión de patógenos al hombre y dejan en evidencia la necesidad de la inclusión de un parámetro parasitológico y viral en el control de la calidad microbiológica de estos productos alimenticios.

The presence of G. intestinalis and C. parvum, E. coli F+ bacteriophages and fecal pollution indicator organisms was determined in shrimp for human consumption marketed in the State of Zulia. Parasites were concentrated from the digestive systems of shrimp pools, detected by formalin-ether and quantified by direct immunofluorescence. E. coli F + bacteriophage and pollution indicator organism concentrations were determined by standard techniques. In this work, G. intestinalis, C. parvum, E. coli F + bacteriophages and E. coli were detected in shrimp for human consumption marketed in the State of Zulia that met the quality criteria of Venezuelan health and safety regulations. 91.5% of the samples analyzed were positive for G. intestinalis (average: 36.6 cyst/100g), 95.3% for C parvum (average: 32.8 oocyst/100g), 100% for E coli F + bacteriophages (average: 2.8 x 103 FPFU/100g) and 71.5% for E. coli (average: 4.3 x 104 MPN/g). Results of this research indicate that shrimp can become a vehicle for transmitting pathogens to humans and demonstrate the need for including a parasitic and viral parameter in microbiological quality control for seafood.

Seroepidemiología de la toxocariasis en una comunidad indígena Yucpa de la Sierra de Perijá al occidente de Venezuela / Seroepidemilogy of toxocariasis in a Yucpa amerindian community from the Perijá Mountains, western Venezuela

El propósito de este estudio fue determinar la seroprevalencia de infección por Toxocara spp en una comunidad indígena de la sierra de Perijá, al occidente de Venezuela, identificando el efecto de los cambios socioculturales sobre los factores de riesgo. Se estudió el 75,4% del total de la comunidad (110 individuos). La determinación de anticuerpos anti-Toxocara spp se realizó a través de una técnica de ELISA comercial. El análisis estadístico se realizó a través de la prueba de Chi cuadrado y la correlación de Spearman. El porcentaje general de infección fue de 21,7%, la más alta prevalencia se observó en el grupo de mayores de 50 años (37,5%). No se apreciaron diferencias estadísticamente significativas con relación al sexo. La prevalencia encontrada fue más alta que la apreciada en poblaciones urbanas y más baja que en otras comunidades indígenas. El proceso de transculturización en esta comunidad indígena es un factor de riesgo para la infección por Toxocara spp

The aim of this study was to determine the Toxocara spp infection seroprevalence in an Amerindian community from western Venezuela, identifying the effect of socio-cultural changes on the risk factors. 75.4% of the community, 110 individuals, were studied. Blood samples were gathered by venous puncture. Determination of anti-Toxocara spp antibodies was carried out using a commercial ELISA technique. The overall prevalence was 21.7%. Higher prevalence was observed in the age group >50 years old (37.5%). There were no statistically significant differences with regard to sex. The prevalence found was higher than that of an urban population and lower than in other indigenous communities. The transculturization process in this indigenous community is a risk factor for Toxocara spp infection

Seroepidemiology of toxoplasmosis in women of childbearing age from a marginal community of Maracaibo, Venezuela / Soroepidemiologia da toxoplasmose em mulheres em idade fértil em comunidade marginal de Maracaibo, Venezuela

The aim of this study was to determine the prevalence of anti-T. gondii total and IgM antibodies in women of childbearing age. One hundred serum samples of women were studied with age range from 11 to 45 years old. Samples were chosen by random. The determination of total antibodies was carried out through the indirect hemagglutination technique and IgM antibodies by ELISA's technique. The statistical analysis was carried out through the Chi square and the Spearman correlation tests. The theoretical estimated incidence of congenital toxoplasmosis was calculated, according to the annual increment of antibody prevalence among the age groups. The overall prevalence of toxoplasmosis was 33 percent, while only six individuals (18.2 percent) were positive to IgM. The highest prevalence was observed in the 11-35 year-old age group. The theoretical estimated incidence was 1.5 for 100 pregnancies in women of 21-25 year-old group; it decreased until 0.1 percent in the 41-45 year-old age group. The findings show a high prevalence of toxoplasmosis in this community with a high infection risk in women of the studied age group and the high cat population observed, suggesting that the transmission way by contaminated soils may play a main role in the spreading of toxoplasmosis in this community.

A finalidade do presente estudo foi determinar a prevalência de anticorpos totais e IgM anti-Toxoplasma gondii, em mulheres em idade fértil. Estudaram-se 100 amostras de soro de mulheres com idade entre 11 e 45 anos. Amostras foram escolhidas ao acaso. A determinação de anticorpos totais foi realizada com a técnica de hemaglutinação indireta e a determinação de anticorpos IgM, pela técnica de ELISA. A análise estatística foi realizada usando a prova do Chi quadrado e a correlação de Spearman. A incidência teórica estimada da toxoplasmose congênita foi calculada de acordo com o incremento anual da prevalência de anticorpos entre os diversos grupos de acordo com a idade. A prevalência geral de toxoplasmose foi de 33 por cento, enquanto somente seis pacientes (l8,2 por cento) foram positivos para IgM. A prevalência maior foi observada no grupo de 11-35 anos de idade. A incidência teórica estimada foi de 1,5 por 100 mulheres grávidas no grupo de 21-25 anos de idade; diminuiu até 0,1 por cento no grupo de 41-45 anos de idade. Os resultados obtidos refletem alta prevalência de toxoplasmose nesta comunidade, além de alto risco de infecção nas mulheres no grupo de idade estudado, sugerindo-se que a transmissão através de fezes de gato, pode ter papel preponderante.

[Seroepidemiology of toxoplasmosis in a Yucpa Amerindian community of Sierra de Perijá, Zulia State, Venezuela]. / Seroepidemiología de la toxoplasmosis en una comunidad indígena Yucpa de la Sierra de Perijá, Estado Zulia, Venezuela.

BACKGROUND: There is a high rate of Toxoplasma gondii infection worldwide. In Latin America the rate is as high as 65% in some populations. AIM: To measure the prevalence of antibodies against Toxoplasma gondii in a native Yucpa community in Venezuela. SUBJECTS AND METHOD: Total serum antibodies measured by indirect hemagglutination and IgM antibodies by ELISA were measured in 94 Yucpa subjects (49 males), aged from 3 months to 100 years. RESULTS: The overall prevalence of infection was 63%. Fifty nine subjects had total antibodies and 14 had IgM antibodies. No significant differences by age or sex, were observed in the proportion of subjects with positive total or IgM antibodies. CONCLUSIONS: The studied individuals had a high prevalence of Toxoplasma gondii infection.

Fasciolosis humana en el municipio Mara estado Zulia Venezuela: prevalencia y factores asociados / Human fasciolosis in Mara municipality Zulia state Venezuela: prevalence and asociated factors

La Fasciolosis humana tiene baja frecuencia en Venezuela; sin embargo, el Municipio Mara es una región altamente endémica para fasciolosis bovina y no existen estudios sobre esta infección parasitaria en humanos. Con el propósito de determinar la prevalencia y factores asociados a la fasciolosis humana en el municipio Mara del estado Zulia, se recolectaron un total de 51 muestras de sangre y de heces. Los sueros se procesaron mediante la técnica de ELISA y “Western blot” (WB) con antígenos excreción-secreción de Fasciola hepatica (AFhES). A los sueros que resultaron positivos se les realizó ELISA IgG anti Toxocara spp, Toxoplasma gondii y cisticerosis. Las muestras de heces se concentraron mediante las técnicas de Ritchie y sedimentación rápida. Dos sueros (3,9 por ciento) fueron positivos a la técnica de ELISA AFhES; estos no reconocieron las moléculas específicas del WB-AFhES, detectadas por sueros de pacientes con infección absolutamente demostrada. Ambos individuos resultaron negativos a IgG anti Toxocara spp, Toxoplasma gondii y cisticerosis, así como también a parásitos intestinales. La prevalencia general de las parasitosis intestinales fue de 52,9 por ciento (27/51), siendo más frecuente los protozoarios que los helmintos. No se encontraron huevos de F. hepatica. Los dos individuos positivos a ELISA AFhES tenían en común trabajar en el corte de pasto fresco. Los resultados obtenidos sugieren que la población ha estado en contacto con F. hepatica, en ausencia de una infección activa por la falta de reconocimiento de las moléculas específicas del WB-AFhES y la ausencia de huevos en las heces. La fasciolosis humana tiene una baja frecuencia en Venezuela, razón por la cual no es sospechada su presencia, existiendo poco conocimiento de esta infección por el personal de salud y la población general.

In Venezuela, human Fasciolosis shows a low frequency. However, Mara Municipality is a highly endemic region for bovine fasciolosis and there are no reports of this parasite infection in humans. To determine the prevalence and associated factors to human fasciolosis in Mara municipality - Zulia state, a total of 51 blood and stool samples were collected. Serums were tested by ELISA and Western Blot (WB) assays, with excretion-secretion antigens of Fasciola hepatica (AFhES). The serum samples that resulted positive by these assays were tested by ELISA IgG anti Toxocara sp, Toxoplasma gondii and cysticerosis. Stool samples were concentrated by the Ritchie and rapid sedimentation techniques. Two serum samples were reactive to ELISA AFhES (3.9 percent) and these did not recognize the specific molecules of WB-AFhES detected by serum from patients with an absolutely demonstrated infection. Both participants were not positive to IgG anti Toxocara sp, Toxoplasma gondii, cysticerosis, and stool samples of these were negative to intestinal parasites. The general prevalence of intestinal parasites was 52.9 percent (27/51), being protozoa more frequent than helminthes. No Fasciola eggs were found. The two positives participants had in common that both had worked as fresh pasture cutters. These results suggest that the population had been in contact with F. hepatica, with no active infection because of the lack of specific molecules recognition and the absence of eggs in stool samples. Human fasciolosis has a low frequency in Venezuela and is underestimated and underrecognized by health workers and the general population.

Técnicas para la detección de Cryptosporidium sp. en sistemas de tratamiento de agua residual / Techniques for Cryptosporidium sp. detection in wastewater treatment systems

En este trabajo se evaluó la aplicabilidad de la técnicas de tinción de Kinyoun e Inmunofluorescencia, para el monitoreo periódico de la calidad parasitológica del agua residual del Sistema de Lagunas de Estabilización "Planta de Tratamiento de Aguas Servidas Sur" de la ciudad de Maracaibo. Se detectó Cryptosporidium sp. en el 100 por ciento de las muestras analizadas por las dos técnicas. Los promedios de Cryptosporidium sp. detectados por la técnica de Kinyoun fueron: en la entrada de la planta 4,9x105 ooquistes/100L, en los módulos primarios 1,2x105 ooquistes/100L, en la laguna facultativas 5,9x104 ooquistes/100L y en la salida 3,0x104 ooquistes/100L, mientras que para C. parvum por inmunofluorescencia fueron: 5,9x104 ooquistes/100L, 7,7x104 ooquistes/100L, 3,0x105 ooquistes/100L y 3,0x104 ooquistes/100L, respectivamente. Se observó una correspondencia del 100 por ciento de positividad en las muestras analizadas por ambas técnicas. Dada las ventajas en facilidad de aplicación, rapidez y costos que ofrece la técnica de Kinyoun, se sugiere su aplicación como técnica de rutina para la evaluación de Cryptosporidium sp. en muestras de agua residual. Se observó la presencia de par sitos en el efluente final, por lo tanto éste no es apto desde el punto de vista parasitológico, para ser empleado con fines de irrigación, sin representar un riesgo para la salud pública.

This work evaluates the applicability of the Kinyoun and immunofluorescence techniques for periodic control of the parasitological quality of wastewater from the stabilization lagoon system “Wastewater Treatment Plant South” in the city of Maracaibo. Cryptosporidium sp. was detected in the 100 percent of the samples analyzed by both techniques. The concentration of Cryptosporidum sp. detected by the Kinyoun technique was: 4.9x105 oocysts/100L at the plant entrance, 1.2x105 oocysts/100L in the primary modules, 5.9x104 oocysts/100L in the facultative lagoon and 3.0x104 oocysts/100L in the final effluent, while those of C. parvum detected by inmunofluorescence were: 5.9x104 oocysts/100L, 7.7x104 oocysts/100L, 3.0x105 oocysts/100L and 3.0x104 oocysts/100L, respectively. A 100 percent correspondence of the results from samples analyzed by both techniques was observed. Given the advantages in ease of application, rapidity and costs offered by the Kinyoun technique, its routine application for evaluating Cryptosporidium sp. in wastewater samples is suggested. The presence of parasites in the final effluent was observed; therefore, from the parasitological viewpoint, it is not apt for irrigation purposes, without representing a risk to human health.

Seroprevalencia de la toxoplasmosis en una población pediátrica del municipio Mara estado Zulia / Toxoplasmosis seroprevalence in a pediatric population Mara municipality, state of Zulia

La Toxoplasmosis es una de las protozoonosis más frecuentes del ser humano. El objetivo de este estudio fue determinar la seroprevalencia de la toxoplasmosis en una población infantil del Municipio Mara, estado Zulia. Se estudiaron 119 muestras de sueros de ambos sexos (53 masculinos y 66 femeninos) con edades comprendidas entre 4-13 años. Los anticuerpos toxoplásmicos se determinaron por de la técnica de hemaglutinación indirecta. El análisis estadístico se realizó a través de la prueba de Chi cuadrado y la correlación de Spearman. La prevalencia general de infección fue de 15,9 por ciento. La frecuencia de sueros positivos fue mayor en el rango de edad de 10-13 años (8/25) con un 32,0 por ciento. Se observó que el número de casos positivos aumentó con relación al grupo de edad. No se observaron diferencias estadísticamente significativas con relación al sexo, sin embargo se apreció una mayor tendencia de positividad para el sexo femenino en el grupo de 10-13 años. La media geométrica fue de 9.479. El rango de títulos positivos fue de 1:64 a 1:2.097.512, el título más bajo fue de 1:64 con 5,26 por ciento (1/19) y el más alto 1:2.097.512 con 5,26 por ciento (1/19). Los resultados obtenidos indican que esta enfermedad es frecuente en esta población infantil.

Toxoplasmosis is one of the most frequent protozoonosis in the human being. The objective of this study was to determine toxoplasmosis seroprevalence in an infantile population from the Mara Municipality, State of Zulia. 119 serum samples from both sexes (53 male and 66 female) with ages between 4-13 years were studied. The toxoplasmic antibodies were determined by the indirect hemaglutination technique. Statistical analysis was done using the Chi square test and Spearman’s correlation. General prevalence of the infection was 15.9 percent. The positive serum frequency was greater in the 10-13 year age range (8/25) with 32.0 percent. It was observed that the number of positive cases increased in relation to the age group. No statistically significant differences related to gender were observed; nevertheless, a greater positive tendency was observed for females in the 10-13 year group. The geometric average was 9.479. The range of positive titles was from 1:64 to 1:2.097.512; the lowest title was 1:64 with 5.26 percent (1/19) and the highest was 1:2.097.512 with 5.26 percent (1/19). Results indicate that this disease is frequent in this infantile population.

Amibiasis: importancia de su diagnóstico y tratamiento: mini-revisión / Amebiasis: importance of the diagnosis and treatment: minireview

El protozoario E. histolytica es el agente etiológico de la amibiasis humana; la identificación de su patogenicidad ha sido de gran ayuda en la búsqueda de antígenos importantes para su inmunodiagnóstico e inmunoprofilaxia. En 1995 se describió el aislamiento y axenización de las dos primeras cepas de E. histolytica venezolanas procedentes de pacientes sintomáticos, denominadas IULA: 1092:1 e IULA: 0593:2. Estas cepas han sido evaluadas a través de estudios de perfiles electroforéticos, demostrándose la presencia del zimodemo de tipo II característico de cepas patógenas. También han mostrado ser de alta virulencia. Además, presentan un complejo patrón de reactividad y la presencia de un antígeno marcador de patogenicidad; el análisis isoenzimático ha mostrado correlación con el análisis genotípico, indicando una organización genotípica propia de una cepa patógena. Con esta cepa se han podido evaluar todos los casos de amibiasis remitidos al Instituto de Inmunología Clínica de la Universidad de Los Andes, y han sido de utilidad en otras localidades al emplear sus antígenos para evaluar poblaciones urbanas e incluso indígenas, por lo que pueden ser usadas como cepas nativas de referencia en los ensayos de diagnóstico y profilaxis. Las limitaciones del examen microscópico, específicamente los falsos diagnósticos de amibiasis, y su incapacidad para discriminar entre infecciones por E. histolytica y E. dispar, han conducido al desarrollo de procedimientos de laboratorio que permiten la detección de componentes de las especies presentes. El éxito de tales procedimientos permitiría una disminución de tratamientos innecesarios, los cuales pueden llevar a resistencia ante las diferentes drogas antiamibianas.

Seroepidemiología de la toxoplasmosis en una comunidad marginal del Municipio Maracaibo, Estado Zulia, Venezuela / Seroepidemiology of toxoplasmosis in a marginal community of Maracaibo, Venezuela

El propósito de la investigación fue determinar la prevalencia de anticuerpos anti-toxoplasma gondii en una comunidad marginal del Municipio Maracaibo, Estado Zulia, Venezuela y si existía asociación entre los factores de riesgo e infección. Se realizó una encuesta epidemiológica que incluyó datos personales, condiciones sanitarias de la vivienda y convivencia con gatos. Se examinaron 254 muestras de suero de individuos de ambos sexos, con un rango de edad de 8 meses a 76 años. La determinación de anticuerpos anti-toxoplasma gondii se realizó a través de la técnica de hemaglutinación indirecta, utilizando un kit disponible comercialmente. Se consideró como reacción positiva diluciones>=1:64. El análisis estadístico se realizó a través de chi cuadrado. La prevalencia de infección fue de 36,6 por ciento observándose que el 21,5 por ciento de los sueros positivos presentaron títulos los considerados no significativos (<=1:64), 51,6 por ciento títulos intermedios (1:128 a 1:512), 24,8 por ciento títulos altos (1:1024 a 1:4096) y 2,1 por ciento títulos muy altos (>=1:8192). El mayor porcentaje de seropositivos (50 por ciento) se observó en el grupo >= de 46 años. No se observaron diferencias estadísticamente significativas en relación al sexo. El chi cuadrado reveló que no existe asociación estadísticamente significativa entre los factores de riesgo (conviviencia con gatos, condiciones sanitarias de la vivienda) y la presencia de infección, sin embargo la toxoplasmosis es frecuente en la comunidad de Puerto Caballo, desempeñando los gatos y las condiciones sanitarias de la vivienda un papel importante en la transmisión de la infección