Outbreak of Carbapenem Resistant High-Risk Clone ST244 <i>Pseudomonas aeruginosa</i> in Dogs and Cats in Algeria

Background/Objectives: Pseudomonas aeruginosa causes chronic infections in humans and animals, especially cats and dogs. This bacterium's ability to adapt and acquire antibiotic resistance traits may complicate and exacerbate antibacterial therapy. This study aimed to evaluate the antibiotic resistance patterns, virulence factors and ability to form biofilm of P. aeruginosa strains isolated from Algerian dogs and cats. Methods: Nineteen samples were collected from healthy and diseased dogs and cats. Isolates were studied for their antibiotic resistance patterns (disc diffusion method), biofilm formation (Microtiter assay) and were Whole genome sequenced (MinION). Results: Nineteen P. aeruginosa strains (15 from dogs and 4 from cats) were isolated. Antibiotic resistance phenotypes were observed against amoxicillin-clavulanic acid (100%), meanwhile resistance towards ticarcillin was 40% (dogs) and 25% (cats), ticarcillin-clavulanic acid was 13.33% and 25% for dogs and cats respectively and imipenem was 75% (cats) and 20% (dogs). 95% of strains were biofilm producers. Different antimicrobial resistance genes (ARGs) were found: beta-lactamase genes mainly PAO, OXA-494, OXA-50 and OXA-396, aminoglycosides gene (aph(3&rsquo;)-IIb), fosA for fosfomycin and catB7 for phenicol. The main high risk STs were ST244, 2788, 388 and 1247. A large panel of virulence genes was detected: exoS, exoT, exoY, lasA, toxA, prpL, algD, rhIA and others. Conclusions: The genetic variety in antibiotic resistance genes of resistant and virulent P. aeruginosa strains in dogs makes public health protection difficult. Continuous monitoring and research in compliance with the One Health policy are needed to solve this problem.