Screening of Aeromonas spp. and their antimicrobial resistance profiles in wild fish and seawater from the Gulf of Antalya, Mediterranean Sea

Aeromonas species are widespread pathogens that cause significant diseases in humans and animals, resulting in severe economic losses in the aquaculture industry. Furthermore, these species have become a greater threat due to recent reports of multidrug-resistant Aeromonas species and the potential transfer of antibiotic resistance genes to important pathogenic bacteria affecting human and animal health. The aim of this study was to investigate the presence of Aeromonas spp., an important zoonotic pathogen, in wild fish species caught in the Gulf of Antalya and in seawater, and to identify the most common Aeromonas species and their antibiotic resistance profiles. Seawater samples from five different coastal points in the Gulf of Antalya and 80 fish caught by local fishermen were bacteriologically examined. Suspected Aeromonas spp. isolates were purified and identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. The resistance profiles of the isolates to 12 antibiotics from 9 different classes were determined by the Kirby- Bauer disk diffusion method in accordance with Clinical and Laboratory Standards Institute criteria. Aeromonas spp. were isolated from the liver and kidney of only one (1.25%) wild fish (Pagellus acarne Risso, 1826) and identified as Aeromonas molluscorum. The isolate was resistant to ampicillin and cefazolin. The multiple antibiotic resistance index was calculated to be 0.16. These findings highlight that wild fish and seawater in the Gulf of Antalya do not pose a risk with respect to multidrug-resistant Aeromonas species that could threaten human health through foodborne infections or direct contact.