spp., .

Listeriosis is a disease caused by , a relevant microorganism as a causative agent of foodborne diseases - FBD. This study aimed to evaluate the distribution of spp., and in different production areas in two small plants (A and B) and two micro-food processing plants (C and D) producing meat derivatives, located in different cities of Colombia. The methodology implemented was . The analysis of sampling points is based on a harmonised tool. . Four samplings in each production plant between 2019 and 2020. . Isolation and identification of microorganisms through conventional microbiology, a semi-automated system, molecular serotyping and clonal characterisation by ERIC-PCR. frequency in the production plants belonging to the study ranged between 5.9 and 28.6 %; for spp., plants A and D had isolated, plant A had the highest proportion, while for geno-serotypes found were: 1/2a, 1/2c, 4a-4c, 4b, 4d - 4e, with geno-serotype 4b as the most frequent. Furthermore, possible persistent isolates were detected in plant C as the feasible sources of contamination, based on failures in flow management, raw material contaminated with lack of standardised cooking processes and transfer of the microorganism through equipment and surfaces. Finally, in three of the four production plants assayed, or spp. were present in the packaging area in some of the samples taken during the study, which calls for increased and frequent monitoring, as well as constant technical support for the control of in micro and small-scale production plants.