Caracterização de Escherichia coli e Salmonella spp. multirresistentes veiculadas por linguiças coloniais dessecadas vendidas em feiras livres no município de Pelotas/RS

Abstract

Colonial sausage is a type of processed meat widely consumed in southern Brazil. It is a ready-to-eat product that can carry pathogens to consumers if not handled properly from production to sale. The risk of transmitting pathogenic multidrug-resistant microorganisms through animal-derived products is well-known worldwide. Therefore, this study aimed to detect and isolate multidrug-resistant bacteria of the genus Salmonella spp. and the species Escherichia coli from colonial sausages sold at open markets in the city of Pelotas. The study also sought to perform molecular characterization of these isolates present in these ready-to-eat products, highlighting their health risks to consumers. A total of 88 samples of these products were obtained. Microbiological analyses were conducted following the methodology recommended by ANVISA for the detection of Salmonella spp. and detection and enumeration of Escherichia coli. To assess multidrug resistance, the Bauer disk diffusion test was performed for six different classes of antimicrobials. The presence of the invA gene was investigated in Salmonella spp. isolates using PCR, and the genes eae, stx, est, elt, ipaH, aggR, CVD432, and aspU were investigated using multiplex PCR for E. coli isolates to determine the pathotypes of thisbacterium. Results showed that 39.7% (35/88) of the samples were positive for Salmonella spp., and 17% (15/88) had E. coli counts above the legal limit. All isolates exhibited resistance to at least three different classes of antimicrobials. Thirty isolates were identified with the presence of the invA gene, characterizing the species Salmonella Typhimurium, and five E. coli isolates presented the eae gene, characterizing enteropathogenic E. coli (EPEC). This study reveals the high risk to consumers due to the transmission of pathogenic multidrugresistant bacteria in colonial sausages sold at open markets in Pelotas. The presence of these microorganisms in these products represents a serious threat to public health.