Occurrence and Antimicrobial Resistance of Acinetobacter spp. in Processing Environments of Slaughterhouses and Meat Processing Facilities

Several species of the genus Acinetobacter are nosocomial pathogens with a well-documented ability to acquire resistance to multiple antibiotics. Although Acinetobacter is one of the most abundant genera in meat processing environments, data on this genus outside of clinical environments remains limited. The objective of this study was to ascertain the prevalence, diversity and antimicrobial resistance profile of Acinetobacter spp. in 200 samples collected from food contact surfaces, non-food contact surfaces, carcasses and final meat cuts across five pork, chicken and beef processing facilities, each comprising physically connected slaughterhouses and meat processing plants. Acinetobacter spp. were detected in 80% (95% CI = 71–87%) and 70% (95% CI = 60–79%) of samples from slaughterhouses and processing plants, respectively. The facilities harboured a wide diversity of Acinetobacter species, with 27 different species identified. Acinetobacter baumannii was the species most frequently detected. Whole-genome sequencing of 18 Acinetobacter spp. isolates revealed the presence of ARGs conferring resistance to beta-lactams, tetracyclines and aminoglycosides, and disclosed phylogenetic relationships with isolates from fresh meat. Phenotypic resistance to beta-lactams, fluoroquinolones, aminoglycosides, folate pathway inhibitors and/or tetracyclines was observed in 77.8% of the sequenced isolates, with 44.4% classified as multidrug-resistant. These findings identify meat processing environments as an important reservoir of Acinetobacter spp. and highlight the need for further investigation to prevent the dissemination of antimicrobial-resistant strains.