MALDI-TOF MS-based identification and antibiotics profiling of Salmonella species isolated from retail chilled chicken in Saudi Arabia

Objectives: Salmonella is a well-known foodborne pathogen that is spread around the world. It causes diseases both in animals and humans. The development of antibiotic-resistant Salmonella strains results in the failure of formerly effective drugs in humans and animals and poses a serious threat to world health. In the Kingdom of Saudi Arabia, the rise in Salmonella prevalence in poultry is seen as a serious problem. Saudi Arabia has endured several epidemics of Salmonella infections with varied patterns of drug resistance in the last few decades. Methods: A total of 112 chilled chicken carcass of five different local poultry companies were procured from retail outlets in Jeddah. The ISO 6579:2002 standard was followed to isolate and identify Salmonella. The isolates were identified using cultural and biochemical features and were further confirmed using (MALDI-TOF MS). Antibiotic susceptibility for each Salmonella isolate was determined using the automated MicroScan WalkAway plus System. Results: Out of the 112 samples, 35 (31.25%) samples harboured Salmonella spp. According to MALDI-TOF MS identification, 34 isolates were recognized as S. Typhimurium or S. Enteritidis with high confidence levels (log (score) values between 2.00 and 3.00), while one isolate was characterized as a Salmonella sp. with a low confidence level (log (score) < 2.00). The antibiotic sensitivity pattern demonstrated resistance to fluoroquinolones, cephalosporin, and penicillin, however, carbapenem was effective against all the isolated Salmonella spp. Out of the 35 isolates, 23 (65.71%) isolates resisted three or more than three different antibiotics and thus were regarded as multi-drug resistant (MDR) strains. Conclusions: The findings of this study indicated the presence of MDR Salmonella species in chilled chicken marketed in Jeddah, Saudi Arabia which highlights potential public health risks. Accordingly, a thorough investigation of the veterinary service, safety and hygienic system of poultry industry, as well as vendors is needed to safeguard the consumer health. (c) 2023 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).