Listeria monocytogenes in hot dog sausages obtained from groceries stores in the city of São paulo – a comparative and retrospective analysis of human listeriosis isolates

Three hundred and ninety four hot dog samples obtained from retail markets (groceries stores)in the city of São Paulo/Brazil were investigated for the presence of Listeria monocytogenesand for the respective serovars of the isolated strains. A total of 56 strains of L.monocytogenes were found. Serovars 1/2a and 1/2c were each identified in 41.2% of thesamples (14/34) and the serovar 4b was found in 17.6% (6/34). It was concluded that Listeriamonocytogenes occur in hot dogs sold at these markets in the city of São Paulo; it waspredominating in the hot dogs samples serovars: 1/2a (41.2%) and serovar 1/2c (41.2%),followed by serovar 4b (17.6%); the serovars isolated from hot dog samples were the sameones associated to outbreaks and sporadic cases including serovar 4b, even though it showed alower percentage against the others serovars detected; it must be considered as routinepractices the monitoring of the thermal treatment during the cooking process of hot dogs, theevaluation of the occurrence level of L.monocytogenes on bench surfaces and equipment usedduring post-thermal treatments, it must be realized the re-pasteurization after packaging; it isvery important to implement the Good Manufacturing Practices – GMP and the HazardAnalysis and Critical Control Point – HACCP in the food industries, restaurants and any foodproduction areas.