Diversity and antibiotic resistance profiles of Listeria monocytogenes serogroups in different food products from Transylvania Region, Central Romania.

The aim of this study was to assess the presence and antimicrobial susceptibility profile of the molecularly serogrouped Listeria monocytogenes isolates in different animal origin food products, collected from a county situated in the historical region of Transylvania, Central Romania. A total of 7.7% (17/221) of the screened samples were positive for L. monocytogenes , with an isolation frequency of 6.2% (8/130) in the ready-to-eat products (i.e., sausages, ham and smoked specialties), 12.8% (6/47) in raw meat (i.e., minced pork, pork organs and snails), and 6.8% (3/44) in dairy (i.e., assortment of cheeses) samples. The identified L. monocytogenes serogroups were: 1/2a-3a (47.1%), 4b-4d-4e (29.4%), 1/2c-3c (11.8%), and 4a-4c (11.8%), respectively. All isolates were resistant to benzylpenicillin and fusidic acid. Resistance was also detected towards oxacillin (88.2%), fosfomycin (82.4%), clindamycin (76.5%), imipenem (52.9%), ciprofloxacin (41.2%), rifampicin (41.2%), trimethoprim - sulfamethoxazole (29.4%) and tetracycline (29.4%). On the other hand, all isolates proved susceptible to gentamicin, moxifloxacin, teicoplanin, vancomycin, tigecycline, erythromycin and linezolid. All tested strains exhibited multidrug resistance, resulting in the expression of a total of 12 resistance profiles. These findings extend the understanding about the spread of an important pathogen in Romanian food products, highlighting a substantial public health issue and medical concern, especially for consumers with a compromised health status.