|Reseña||Int J Food Microbiol. 2012; 156(2):152-60. Enlace|
|Autores||Leiro JM, Piazzon C, Domínguez B, Mallo N, Lamas J.|
El consumo y la manipulación de peces infectados con microsporidios pueden ser factores de riesgo para los seres humanos. Después de evaluar la viabilidad de las esporas tras diferentes tratamientos físicos y químicos para su inactivación, los resultados sugieren que tanto la congelación como el calentamiento son tratamientos efectivos para destruir las esporas de microsporidios en rape blanco europeo, y que podría emplearse un tratamiento con etanol al 70% para el procesado y manipulación del pescado.
Microsporidia are a large diverse group of intracellular parasites now considered as fungi. They are particularly prevalent in fish and are recognized as important opportunistic parasites in humans. Although the mode of transmission of microsporidia has not been fully clarified, the consumption and manipulation of infected fish may be a risk factor for humans. Comparative analysis of rDNA sequence revealed that the microsporidians used in the present study had 99-100% identity with anglerfish microsporidians of the genus Spraguea and very low identity with microsporidians that infect humans. Microsporidian spores were exposed to different physical and chemical treatments: freezing at -20°C for 24-78 h, heating at 60°C for 5-15 min, microwaving at 700 W, 2.45 GHz for 15-60s, and treatment with ethanol at concentrations of between 1 and 70% for 15 min. The viability of thespores after each treatment was evaluated by two methods: a) haemocytometer counts, measuring the extrusion of the polar filament in control and treated spores, and b) a fluorometric method, testing the membrane integrity by propidium iodide exclusion. The results of both methods were concordant. Spores were inactivated by freezing at -20°C for more than 48 h, by heating to 60°C for 10 min and by microwaving at 750 W, for 20s. Exposure to 70% ethanol for 15 min also inactivated microsporidian spores. The results suggest that both freezing and heating are effectivetreatments for destroying microsporidian spores in European white anglerfish, and that 70% ethanol could be used by fish processors to disinfect their hands and the utensils used in processing fish. The fluorometric method can be used as an alternative to haemocytometer counts in disinfection studies aimed at establishing strategies for inactivating and reducing the viability and the potential infectivity of microsporidians present in fish or in the environment.
|Grupo de investigación||
GI-2109 – Sistemas de liberación de medicamentos e inmunoparasitología zoonosis protozoarias de transmisión hídrica – Parasitología Humana y Animal enlace