CARRIAGE OF MULTIDRUG-RESISTANT ACINETOBACTER SPP. IN FARMED-, WILD ANIMALS AND ENVIRONMENT

Objectives: The emerging spread of multidrug (MDR) and carbapenem-resistant Acinetobacter strains has become a significant threat, aggravating the clinical signs of COVID-19 patients. The aims of this study were to: -investigate the involvement of Acinetobacter calcoaceticus-baumannii complex (ACB) and not-ACB strains in farmed-, wild-animals, and environment; -evaluate the carriage of phenotypic antibiotic-resistance profiles. Materials and methods: From 284 farmed-, 122 wild-animals and 45 environmental specimens, Acinetobacter spp. was investigated by culture and MALDI-TOF/MS identification. MICs (E-test) against polimixins, amoxicillin-clavulanic acid, and Kirby-Bauer for carbapenems, cephalosporines, fluoroquinolones, aminoglycosides, tetracyclines, sulfonamides, and monobactams, were performed. Results: Acinetobacter - (59.1%), wild-animals (22.7%), and environment (18.2%). Members of ACB- (18.2%) and not-ACB complex (81.8%) were identified. All strains resulted susceptible to aminoglycosides and polymyxins. A. baumannii (13.6%) and A. dijkshoorniae (4.5%) were isolated from all the three ecosystems, showing a multidrug-resistant profile towards the same five antibiotic classes, including carbapenems. A. lwoffii, A. venetianus, A. johnsonii, A. haemolyticus, A. junii, A. vivianii and A. courvalinii recorded a lower multidrug-resistance (66.7%) compared to what was obtained for ACB-complex strains (100%, P-animals. The wild population showed a significant higher resistance for carbapenems (P ) and tetracyclines (P This surprisingly reflects what observed for the environmental Acinetobacter strains, precisely a resistance of 75% both towards carbapenems, tetracyclines and monobactams. Conclusions: This study highlights the role of wild and environmental ecosystems as potential reservoirs for MDR ACB and not-ACB complex isolates. A One-Health approach and a constant surveillance are needed.