Micro-organismos patogênicos em pescados do estuário da Lagoa dos Patos

Abstract

In recent years, the fish consumption has been increasing, since it provides protein, has low amount of saturated fat and is rich in micronutrients, as well as being a source of fatty acids that can offer health benefits. However, the fish is a potential vehicle for microorganisms that can cause diseases in humans, because they are subject to contamination by microorganisms acquired in the aquatic environment, as well as during harvesting, handling and shipping. Thirteen landings of fish were monitored and 130 fish (65 integer and 65 clean) were analyzed for the presence of Vibrio parahaemolyticus and Salmonella enterica. Fish from Lagoa dos Patos estuary were collected on the arrival and after being processed, and then analyzed to verify its contamination. In order to compare the isolates, rep-PCR analysis was performed. The species colected were croakers (Micropogonias furnieri), gray mullet (Mugil platanus) and the flounder (Paralichthys orbignyanus). V. parahaemolyticus was isolated from 4.61 % of whole fish samples and 4.61 % of gutted fish and ready to trade. S. enterica was isolated from 1.54% of gutted fish. Four V. parahaemolyticus strains showed identical profile bands, one from whole fish and one from gutted fish from the both the second landing, and two from gutted fish from the third landing. Two other strains came from whole fish from different landings and has showed distinct banding profiles. On the second landing, the fish remained contaminated with the same bacterial strain even after gutting and hygienization, when ready for sale, indicating that these procedures were not enough to eliminate the microorganism. On the third landing, probably a cross contamination from some other contaminated fish has occurred. S. enterica was identified in two samples of fish already processed, that came from the same landing and the two strains showed the same bands profiles. As there was no isolation of this microorganism in the whole fish, it is assumed that the cause of contamination with S. enterica is due to hygienic and sanitary failures in the evisceration process, such as contaminated utensils or hands. V. parahaemolyticus naturally occurs on the fish of Lagoa dos Patos estuary, and can remain in the fish after gutting and cleaning. S. enterica may be present in fish ready for sale, probably due to improper sanitary-hygienic practices during processing since this bacterium was not isolated from the whole fish. There is a need to guide the handlers about hygienic and sanitary habits, besides a significant improvement in cleaning and sanitizing operations, in order to eliminate the microbiological risks and ensure the food safety.