A system was developed to identify and quantify up to seven species of helminth eggs (Ascaris lumbricoides -fertile and unfertile eggs-, Trichuris trichiura, Toxocara canis, Taenia saginata, Hymenolepis nana, Hymenolepis diminuta, and Schistosoma mansoni) in wastewater using different image processing tools and pattern recognition algorithms. The system was developed in three stages. Version one was used to explore the viability of the concept of identifying helminth eggs through an image processing system, while versions 2 and 3 were used to improve its efficiency. The system development was based on the analysis of different properties of helminth eggs in order to discriminate them from other objects in samples processed using the conventional United States Environmental Protection Agency (US EPA) technique to quantify helminth eggs. The system was tested, in its three stages, considering two parameters: specificity (capacity to discriminate between species of helminth eggs and other objects) and sensitivity (capacity to correctly classify and identify the different species of helminth eggs). The final version showed a specificity of 99% while the sensitivity varied between 80 and 90%, depending on the total suspended solids content of the wastewater samples. To achieve such values in samples with total suspended solids (TSS) above 150 mg/L, it is recommended to dilute the concentrated sediment just before taking the images under the microscope. The system allows the helminth eggs most commonly found in wastewater to be reliably and uniformly detected and quantified. In addition, it provides the total number of eggs as well as the individual number by species, and for Ascaris lumbricoides it differentiates whether or not the egg is fertile. The system only requires basically trained technicians to prepare the samples, as for visual identification there is no need for highly trained personnel. The time required to analyze each image is less than a minute. This system could be used in central analytical laboratories providing a remote analysis service.

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<p>Objetivo: Establecer la asociación de la carga del cuidador familiar con el tiempo de cuidado y el grado de funcionalidad de la persona anciana campesina. Materiales y método: Estudio cuantitativo de tipo transversal con alcance correlacional, con una muestra de 50 cuidadores familiares. Fueron aplicados: una encuesta sociodemográfica; escala de Zarit, que mide la carga del cuidador y el índice de Barthel, que mide el grado de dependencia funcional. Resultados: Los cuidadores familiare generalmente son mujeres (76 %); mayores de 60 años (50 %), casados (40 %) y solteros (30 %); con bajo nivel socioeconómico (94 %) y educativo (66 %). No se encontró una asociación significativa entre carga del cuidador y el grado de funcionalidad (p = 0,249), tampoco entre la carga del cuidador y el tiempo como cuidador (p = 0,476). Conclusiones: Alta proporción de mujeres campesinas son cuidadoras familiares. El estudio reporta que el tiempo de cuidado y el grado de funcionalidad del anciano no son predictores de carga de cuidado en el cuidador familiar campesino. Se requieren más investigaciones e indagar si hay aspectos culturales que influyen en la experiencia y construcción de significados del cuidado. Se sugiere la necesidad de programas educativos dirigidos a cuidadoras campesinas mediante procesos de autorreconocimiento y autodeterminación de acuerdo con su cultura y capacidades.</p>

Helminth eggs are among the most important biological contaminants in environmental engineering. They pose a significant health risk associated with poor sanitation, the use of contaminated water for irrigation, and the disposal of excreta or sludge to land. Helminths are parasitic worms transmitted to humans via their eggs, which is the infective stage of their life cycle. They are therefore relevant to public health and environmental fields due to their low infectious dose, their persistence in the environment (up to several years), and their high resistance to conventional disinfection processes. The evaluation of the efficiency of any process of inactivation, through the determination of the viability of these parasites, is fundamental, but the traditional incubation technique requires 20 days to determine both the viability and the infectivity of nematode eggs. However, the present study found that, using an inactivation process at a temperature of 60 °C for 1 hour and incubation at 28 °C and 34 °C, the absence of division of the nucleus of eggs of species from two genera, Ascaris lumbricoides and Toxocara canis, showed them to be inactivated following only 48 hours of incubation. Similar inactivation results were observed using an automatic system as long as the eggs were inactivated. The minimum time required to evaluate the inactivation of nematode eggs through the incubation technique was 48 hours.

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