Virulence and Antimicrobial Resistance of <i>Listeria monocytogenes</i> Isolated from Ready-to-Eat Food Products in Romania

Mihaela Niculina Duma; Laurenţiu Mihai Ciupescu; Sorin Daniel Dan; Oana Lucia Crisan-Reget; Alexandra Tabaran

doi:10.3390/microorganisms12050954

Microorganisms (May 2024)

Virulence and Antimicrobial Resistance of <i>Listeria monocytogenes</i> Isolated from Ready-to-Eat Food Products in Romania

Mihaela Niculina Duma,
Laurenţiu Mihai Ciupescu,
Sorin Daniel Dan,
Oana Lucia Crisan-Reget,
Alexandra Tabaran

Affiliations

Mihaela Niculina Duma: Laboratory of Food Microbiology, Sanitary Veterinary Directorate for Food Safety, 400621 Cluj-Napoca, Romania
Laurenţiu Mihai Ciupescu: The Institute of Hygiene and Veterinary Public, The National Sanitary Veterinary Authority for Food Safety, Campul Mosilor 5, 013701 Bucharest, Romania
Sorin Daniel Dan: Department of Animal Husbandry and Public Health, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania
Oana Lucia Crisan-Reget: Department of Animal Husbandry and Public Health, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania
Alexandra Tabaran: Department of Animal Husbandry and Public Health, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania

DOI: https://doi.org/10.3390/microorganisms12050954
Journal volume & issue: Vol. 12, no. 5
p. 954

Abstract

Read online

Listeria monocytogenes (L. monocytogenes) poses a significant threat to food safety due to its ability to cause severe human illness and its resistance to various antibiotics and environmental conditions. This study investigated the prevalence, serotype distribution, virulence gene profiles, and antimicrobial resistance patterns of L. monocytogenes in ready-to-eat (RTE) food products from Romania. A total of 8151 samples were analyzed, including various processed dairy, bovine, poultry, pork, and fish products. Bacterial isolation was conducted using the classical standard method, followed by confirmation through biochemical and molecular testing. Among the isolated strains, serotypes 1/2a, 1/2b, and 1/2c were identified, with a prevalence of 75% for serotype 1/2a. Additionally, virulence genes specific to listeriolysin O (hlyA) and regulatory factor A (prfA) were detected in all isolates. Antimicrobial susceptibility testing revealed varying resistance patterns among the L. monocytogenes strains. Trimethoprim-sulfamethoxazole and oxacillin showed the highest prevalence of resistance at 26.92% and 23.07%, respectively. However, all strains remained susceptible to ciprofloxacin, levofloxacin, and moxifloxacin. Notably, 23.07% of the isolates exhibited multidrug resistance, with the most common pattern being resistance to oxacillin, penicillin, and tetracycline. Analysis of antimicrobial resistance genes identified tetracycline resistance genes, particularly tet(C), tet(M), and tet(K), in a significant proportion of isolates. The presence of ampC and dfrD genes was also notable, indicating potential mechanisms of resistance. These results emphasize the necessity for ongoing surveillance of L. monocytogenes in RTE foods and emphasize the importance of thorough monitoring of antimicrobial resistance to guide public health strategies within the European Union.

Published in Microorganisms

ISSN: 2076-2607 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Science: Biology (General)
Website: https://www.mdpi.com/journal/microorganisms

About the journal

Abstract

Keywords