Salmonella Serovars Distribution in Poultry Meat and Genetic Characterization of Antimicrobial-Resistant Isolates: A Five-Year Monitoring in Sicily
- 1Experimental Zooprophylactic Institute of Sicily A. Mirri, 90129 Palermo, Italy
- 2Department of Biological, Chemical and Pharmaceutical Sciences and Technologies Department, University of Palermo, 90128 Palermo, Italy
Abstract
Salmonellosis is one of the most frequently reported zoonoses, and broiler meat/meat products are among its main vehicles of transmission. Continuous monitoring on Salmonella serovars and the spread of antimicrobial resistance is essential for epidemiological surveillance. From 2021 to 2025, a total of 350 poultry samples were collected in Sicily and analyzed for Salmonella spp. detection, serotyping and antimicrobial resistance (AMR) phenotyping. Overall, 101/350 samples tested positive for Salmonella spp. Eight serovars were identified with S. Infantis being the most prevalent, followed by S. Kentucky, S. Enteritidis, S. Strathcona, S. Agona, S. Corvallis, S. Toulon, S. Virchow. The following resistance percentages were revealed: 78.7% (144/183)—tetracycline, 68.9% (126/183)—trimethoprim-sulfamethoxazole, 51.9% (95/183)—penicillins, 35.0% (64/183)—third-generation cephalosporins, 33.3% (61/183)—aminoglycosides, 4.9% (9/183)—chloramphenicol, 2.2% (4/183)—fluoroquinolones, 0% (0/183)—imipenem. The following genetic determinants were searched in a selected subset of 46 isolates resistant/intermediate resistant (R/I) to third-generation cephalosporins or fluoroquinolones: blaCTX-M-1, blaCTX-M-2, blaCTX-M-4, blaCMY-2, blaTEM, blaOXA, blaSHV (third-generation cephalosporins); qnrA, qnrB, qnrC, qnrD, qnrS, qepA, oqxAB, aac(6′)-Ib (fluoroquinolones) and intI1. High proportions of R/I isolates (78.6% for third-generation cephalosporins, 100% for fluoroquinolones) carried at least one of the resistance determinants. All of them carried intI1. Our data confirm that poultry meat and poultry-based foods represent important vehicles of Salmonella and that S. Infantis is the predominant serovar. The high rate of AMR is of concern for human safety and environmental health, especially referring to the highest priority and critically important antimicrobials (hpCIAs) such as third-generation cephalosporins.
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BibTeX
@article{castello2026salmonella,
title = {{Salmonella Serovars Distribution in Poultry Meat and Genetic Characterization of Antimicrobial-Resistant Isolates: A Five-Year Monitoring in Sicily}},
author = {Annamaria Castello and Vincenzina Alio and Ruggero Baviera and Giuseppa Oliveri and Valeria Gargano and Maria Rita Schiavo and Antonina Zimmardi and Cinzia Cardamone and Rosa Alduina and Antonella Costa},
journal = {International Journal of Molecular Sciences},
year = {2026},
month = nov,
doi = {10.3390/ijms27219876},
url = {https://www.mdpi.com/1422-0067/27/21/9876},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Salmonella Serovars Distribution in Poultry Meat and Genetic Characterization of Antimicrobial-Resistant Isolates: A Five-Year Monitoring in Sicily
AU - Annamaria Castello
AU - Vincenzina Alio
AU - Ruggero Baviera
AU - Giuseppa Oliveri
AU - Valeria Gargano
AU - Maria Rita Schiavo
AU - Antonina Zimmardi
AU - Cinzia Cardamone
AU - Rosa Alduina
AU - Antonella Costa
PY - 2026
DA - 2026/11/04
JO - International Journal of Molecular Sciences
DO - 10.3390/ijms27219876
UR - https://www.mdpi.com/1422-0067/27/21/9876
AB - Salmonellosis is one of the most frequently reported zoonoses, and broiler meat/meat products are among its main vehicles of transmission. Continuous monitoring on Salmonella serovars and the spread of antimicrobial resistance is essential for epidemiological surveillance. From 2021 to 2025, a total of 350 poultry samples were collected in Sicily and analyzed for Salmonella spp. detection, serotyping and antimicrobial resistance (AMR) phenotyping. Overall, 101/350 samples tested positive for Salmonella spp. Eight serovars were identified with S. Infantis being the most prevalent, followed by S. Kentucky, S. Enteritidis, S. Strathcona, S. Agona, S. Corvallis, S. Toulon, S. Virchow. The following resistance percentages were revealed: 78.7% (144/183)—tetracycline, 68.9% (126/183)—trimethoprim-sulfamethoxazole, 51.9% (95/183)—penicillins, 35.0% (64/183)—third-generation cephalosporins, 33.3% (61/183)—aminoglycosides, 4.9% (9/183)—chloramphenicol, 2.2% (4/183)—fluoroquinolones, 0% (0/183)—imipenem. The following genetic determinants were searched in a selected subset of 46 isolates resistant/intermediate resistant (R/I) to third-generation cephalosporins or fluoroquinolones: blaCTX-M-1, blaCTX-M-2, blaCTX-M-4, blaCMY-2, blaTEM, blaOXA, blaSHV (third-generation cephalosporins); qnrA, qnrB, qnrC, qnrD, qnrS, qepA, oqxAB, aac(6′)-Ib (fluoroquinolones) and intI1. High proportions of R/I isolates (78.6% for third-generation cephalosporins, 100% for fluoroquinolones) carried at least one of the resistance determinants. All of them carried intI1. Our data confirm that poultry meat and poultry-based foods represent important vehicles of Salmonella and that S. Infantis is the predominant serovar. The high rate of AMR is of concern for human safety and environmental health, especially referring to the highest priority and critically important antimicrobials (hpCIAs) such as third-generation cephalosporins.
SN - 1422-0067
ER -