Antibiotic Resistance and Virulence Profiles of Strains Isolated from Wild Birds in Poland.

Wild animals are increasingly reported as carriers of antibiotic-resistant and pathogenic bacteria including . However, the role of free-living birds as reservoirs for potentially dangerous microbes is not yet thoroughly understood. In our work, we examined strains from wild birds in Poland in relation to their antimicrobial agents susceptibility, virulence and phylogenetic affiliation. Identification of was performed using MALDI-TOF mass spectrometry. The antibiotic susceptibility of the isolates was determined by the broth microdilution method, and resistance and virulence genes were detected by PCR. bacteria were isolated from 32 of 34 samples. The strains were most often classified into phylogenetic groups B1 (50%) and A (25%). Resistance to tetracycline (50%), ciprofloxacin (46.8%), gentamicin (34.3%) and ampicillin (28.1%) was most frequently reported, and as many as 31.2% of isolates exhibited a multidrug resistance phenotype. Among resistance genes, (31.2% of isolates) and (28.1%) were identified most frequently, while (31.2%) and (28.1%) were the most common virulence-associated genes. Five strains were included in the APEC group. The study indicates that wild birds can be carriers of potentially dangerous strains and vectors for the spread of resistant bacteria and resistance determinants in the environment.