[Spatial distribution of intestinal parasites in the City of La Plata, Argentina]. / Distribución espacial de las parasitosis intestinales en la Ciudad de La Plata, Argentina.

Parasitosis analysis at regional levels is simplified by the use of the Geographic Information System (GIS), which enables the identification of areas with different degrees of vulnerability. We analyzed the spatial distribution of intestinal parasites in La Plata district and their relationship with socio-environmental conditions in order to identify areas with different degrees of epidemiological risk. An epidemiological survey was completed; stool samples were collected and analyzed by Ritchie's method. Levels of precariousness and vulnerability (Iv rate) were calculated and compared to the parasitological results. Parasitological and environmental analysis were carried out on a total of 653 individuals, of whom 585 (89.6%) were children and 68 (10.4%) adults. The analysis indicated that the most vulnerable (Iv = 3-4) were those located in areas with less access to urban infrastructure services. The Iv was strongly associated with the overall prevalence of intestinal parasitosis and the 4 pathogenic species related to the fecal contamination of the environment: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana and Giardia lamblia (p < 0.01). On the other hand, Enterobius vermicularis, a parasite not related to the sanitary condition of its host, was not associated with the Iv. Statistical association between poverty and parasitosis was noted; the greater the Iv, higher the incidence of parasites (p < 0.01). GIS allowed zoning socio-environmental variables in an increasing gradient of unfavorable conditions and their relationship to the presence of pathogenic species. The continuity of these studies in different regions of Argentina contributes to the determination of health risk areas.

Distribución espacial de las parasitosis intestinales en la ciudad de La Plata, Argentina

El análisis de las parasitosis a diferentes escalas (regional, local) se facilita por el Geographic Information System (GIS), que permite identificar áreas con distinto grado de vulnerabilidad. El objetivo del trabajo fue analizar la distribución espacial de las parasitosis intestinales en el partido de La Plata, estableciendo su relación con las condiciones socio-ambientales para identificar áreas con diferente riesgo epidemiológico. Se completó una encuesta epidemiológica y se tomaron muestras seriadas de materia fecal, analizadas por la técnica de Ritchie. Se calcularon niveles de precariedad y vulnerabilidad (Iv), y se compararon con los resultados parasitológicos. Se analizaron parasitológica y ambientalmente 653 personas, de las cuales 585 (89.6%) eran niños y 68 (10.4%) adultos. El análisis indicó que los más vulnerables (Iv = 3-4) estaban en el sector con menor acceso a servicios de infraestructura urbana. El índice se encontró fuertemente asociado a la prevalencia total de parasitosis intestinales y a las 4 especies patógenas asociadas a la contaminación fecal del ambiente: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana y Giardia lamblia (p < 0.01). Enterobius vermicularis, parásito no vinculado a la condición sanitaria de sus hospedadores, no se asoció al Iv. Hubo asociación estadística entre precariedad y parasitosis y se halló que a mayor Iv mayor frecuencia de parasitosis (p < 0.01). El uso de GIS permitió zonificar las variables socioambientales en un gradiente creciente de condiciones desfavorables y su relación con la presencia de especies patógenas. La continuidad de estos estudios en diferentes regiones de Argentina contribuye a la determinación de áreas en riesgo sanitario.

Parasitosis analysis at regional levels is simplified by the use of the Geographic Information System (GIS), which enables the identification of areas with different degrees of vulnerability. We analyzed the spatial distribution of intestinal parasites in La Plata district and their relationship with socio-environmental conditions in order to identify areas with different degrees of epidemiological risk. An epidemiological survey was completed; stool samples were collected and analyzed by Ritchie's method. Levels of precariousness and vulnerability (Iv rate) were calculated and compared to the parasitological results. Parasitological and environmental analysis were carried out on a total of 653 individuals, of whom 585 (89.6%) were children and 68 (10.4%) adults. The analysis indicated that the most vulnerable (Iv = 3-4) were those located in areas with less access to urban infrastructure services. The Iv was strongly associated with the overall prevalence of intestinal parasitosis and the 4 pathogenic species related to the fecal contamination of the environment: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana and Giardia lamblia (p < 0.01). On the other hand, Enterobius vermicularis, a parasite not related to the sanitary condition of its host, was not associated with the Iv. Statistical association between poverty and parasitosis was noted; the greater the Iv, higher the incidence of parasites (p < 0.01). GIS allowed zoning socio-environmental variables in an increasing gradient of unfavorable conditions and their relationship to the presence of pathogenic species. The continuity of these studies in different regions of Argentina contributes to the determination of health risk areas.

Distribución espacial de las parasitosis intestinales en la ciudad de La Plata, Argentina

El análisis de las parasitosis a diferentes escalas (regional, local) se facilita por el Geographic Information System (GIS), que permite identificar áreas con distinto grado de vulnerabilidad. El objetivo del trabajo fue analizar la distribución espacial de las parasitosis intestinales en el partido de La Plata, estableciendo su relación con las condiciones socio-ambientales para identificar áreas con diferente riesgo epidemiológico. Se completó una encuesta epidemiológica y se tomaron muestras seriadas de materia fecal, analizadas por la técnica de Ritchie. Se calcularon niveles de precariedad y vulnerabilidad (Iv), y se compararon con los resultados parasitológicos. Se analizaron parasitológica y ambientalmente 653 personas, de las cuales 585 (89.6%) eran niños y 68 (10.4%) adultos. El análisis indicó que los más vulnerables (Iv = 3-4) estaban en el sector con menor acceso a servicios de infraestructura urbana. El índice se encontró fuertemente asociado a la prevalencia total de parasitosis intestinales y a las 4 especies patógenas asociadas a la contaminación fecal del ambiente: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana y Giardia lamblia (p < 0.01). Enterobius vermicularis, parásito no vinculado a la condición sanitaria de sus hospedadores, no se asoció al Iv. Hubo asociación estadística entre precariedad y parasitosis y se halló que a mayor Iv mayor frecuencia de parasitosis (p < 0.01). El uso de GIS permitió zonificar las variables socioambientales en un gradiente creciente de condiciones desfavorables y su relación con la presencia de especies patógenas. La continuidad de estos estudios en diferentes regiones de Argentina contribuye a la determinación de áreas en riesgo sanitario.(AU)

Parasitosis analysis at regional levels is simplified by the use of the Geographic Information System (GIS), which enables the identification of areas with different degrees of vulnerability. We analyzed the spatial distribution of intestinal parasites in La Plata district and their relationship with socio-environmental conditions in order to identify areas with different degrees of epidemiological risk. An epidemiological survey was completed; stool samples were collected and analyzed by Ritchies method. Levels of precariousness and vulnerability (Iv rate) were calculated and compared to the parasitological results. Parasitological and environmental analysis were carried out on a total of 653 individuals, of whom 585 (89.6%) were children and 68 (10.4%) adults. The analysis indicated that the most vulnerable (Iv = 3-4) were those located in areas with less access to urban infrastructure services. The Iv was strongly associated with the overall prevalence of intestinal parasitosis and the 4 pathogenic species related to the fecal contamination of the environment: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana and Giardia lamblia (p < 0.01). On the other hand, Enterobius vermicularis, a parasite not related to the sanitary condition of its host, was not associated with the Iv. Statistical association between poverty and parasitosis was noted; the greater the Iv, higher the incidence of parasites (p < 0.01). GIS allowed zoning socio-environmental variables in an increasing gradient of unfavorable conditions and their relationship to the presence of pathogenic species. The continuity of these studies in different regions of Argentina contributes to the determination of health risk areas.(AU)

Distribución espacial de las parasitosis intestinales en la Ciudad de La Plata, Argentina. / [Spatial distribution of intestinal parasites in the City of La Plata, Argentina].

Parasitosis analysis at regional levels is simplified by the use of the Geographic Information System (GIS), which enables the identification of areas with different degrees of vulnerability. We analyzed the spatial distribution of intestinal parasites in La Plata district and their relationship with socio-environmental conditions in order to identify areas with different degrees of epidemiological risk. An epidemiological survey was completed; stool samples were collected and analyzed by Ritchies method. Levels of precariousness and vulnerability (Iv rate) were calculated and compared to the parasitological results. Parasitological and environmental analysis were carried out on a total of 653 individuals, of whom 585 (89.6

) were children and 68 (10.4

) adults. The analysis indicated that the most vulnerable (Iv = 3-4) were those located in areas with less access to urban infrastructure services. The Iv was strongly associated with the overall prevalence of intestinal parasitosis and the 4 pathogenic species related to the fecal contamination of the environment: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana and Giardia lamblia (p < 0.01). On the other hand, Enterobius vermicularis, a parasite not related to the sanitary condition of its host, was not associated with the Iv. Statistical association between poverty and parasitosis was noted; the greater the Iv, higher the incidence of parasites (p < 0.01). GIS allowed zoning socio-environmental variables in an increasing gradient of unfavorable conditions and their relationship to the presence of pathogenic species. The continuity of these studies in different regions of Argentina contributes to the determination of health risk areas.

Socio-environmental conditions, intestinal parasitic infections and nutritional status in children from a suburban neighborhood of La Plata, Argentina.

We analyzed intestinal parasitic infections in children aged 1-12 years from a poor neighborhood in La Plata, Argentina, and determined the correlations with their nutritional status and socio-environmental conditions. We performed parasitological analyses with anal brushed technique (for Enterobius vermicularis eggs) and fecal samples, employing the techniques of Ritchie, Carles Barthelemy and Willis. The worm burdens of nematodes were estimated by means of Kato Katz technique. Low weight-for-age (underweight), height-for-age (stunting) and weight-for-height (wasting) were calculated based on the 5th centile of the WHO 2006 (children under 5) and CDC 2000 (older children and adolescents) growth references. We also analyzed samples of soil, water, and canine feces and surveyed other domestic and environmental data using structured questionnaires to each child's parents. To associate the parasitological, anthropometric and socio-environmental data, a categorical analysis of principal components (catPCA) was conducted. In the first axis of catPCA, the correlations among socio-environmental variables showed a gradient of "relative welfare". The eigenvectors showed the most influential variables in the analysis were promiscuity (0.0765), father's education (-0.741), crowding (0.727), wastewater disposal (-0.658), mother's education (-0.574), and flooding (-0.409). The 85% of children were parasitized and 79.6% polyparasitized. The 27.7% of children had deficit in some nutritional status indicator, being the stunting the most prevalent deficit (16.8%). There also found parasites in 42% of the dog feces, 53% of the soil samples, and non-pathogenic amoebae in the water samples. The SEV was mainly associated with geohelminths and stunting, especially among the poorest children. The study evidences that living conditions are variable within this population. Part of these variations could be linked to the differences in the extent to which parents are able to use their scant resources to influence their children's morbidity. Further studies need to be done from a qualitative approach.

Estudio comparativo de recuperación de formas parasitarias por tres diferentes métodos de enriquecimiento coproparasitológico / Comparative study of parasitic forms recuperation using three different coproparasitoscopic methods

Se analizaron 165 muestras fecales seriadas, utilizando dos métodos de sedimentación: Ritchie (R) y Carles Barthelemy (CB) y uno de flotación: Willis (W), con el fin de optimizar el diagnóstico de los parásitos intestinales y determinar la eficacia de las técnicas. Se hallaron parásitos en 119 (72,1 por ciento) de los analizados. Hubo diferencias significativas en la recuperación de protozoos (p < 0,001), observándose 81,4 por ciento (R), 77,4 por ciento (CB), y 57,8 por ciento (W). Blastocystis hominis, G.lamblia, Ascaris lumbricoides y Trichuris trichiura se recuperaron con mayor frecuencia mediante sedimentación, resultando más efectivo el método de Ritchie (p < 0,05).

A total of 165 fecal samples were analyzed, using two sedimentation methods: Ritchie (R), Carles Barthelemy (CB), and one of flotation: Willis (W), in order to optimize intestinal parasites diagnosis and to determine the techniques effectiveness. Parasites were found in 119 (72,12%) of those analyzed. Significant differences were in protozoa recovery (p < 0,001), being observed 81.4% (R), 77.4% (CB), and 57.8% (W). Blastocystis hominis, Giardia lamblia, Ascaris lumbricoides and Trichuris trichiura were recovered more frequency by means of sedimentation, being Ritchie´s method the most effective one (p < 0.05).