Characterization of Listeria monocytogenes from food and food-related settings.
Listeriosis is a serious public health concern due to its high fatality rates. The present investigation screened for the occurrence of Listeria monocytogenes in food and food-related environments by analyzing samples from a cheese making factory, a slaughterhouse and a supermarket. Among the eighty-seven samples analyzed, thirty-four isolates were recovered and subsequently evaluated regarding genomic diversity, antibiotic susceptibility and virulence. Twenty-one L. monocytogenes were allocated to serogroup 1/2a-3a, ten assigned to serogroup 4b-4e-4ab and three to serogroup 1/2c-3c. Results obtained also detected the presence of L. monocytogenes isolates resistant to two clinically relevant antibiotics for the treatment of listeriosis, ampicillin and penicillin. Overall, data gathered disclosed the occurrence of listeria isolates with high pathogenicity potential at all very distinct sampling sites, reinforcing the need for an effective surveillance network designed for detecting the presence of L. monocytogenes in food products and food processing environments.