Mamadou Koné^{1, 2,}, Kalpy Julien Coulibaly², Kouamé Éric Yao¹, Sabine N'Dri Vakou², Kouamé René Yao², Mireille Dosso², Valentin N'douba¹

Aeromonas is a common bacterium in aquatic habitats and recognised as an occasional fish pathogen. The present study aimed at determining the prevalence and distribution of Aeromonas in tilapias from the Ebrié Lagoon (Côte d'Ivoire). The extracellular virulence factors and antibiogram of isolates were also examined. The bacteriological analysis of 512 tilapias showed a prevalence of 10.93%. Out of 87 isolated strains, 6 species were identified by Malditof, 3 of which were dominant, Aeromonas jandaei (24%), A. caviae (23%), A. hydrophila (22%) and 3 less represented, A. sobria (13%), A. veronii (10%), A. trota (8%) Aeromonas jandaei and A. hydrophila were more frequent in the gut than in the gills. All isolates produced gelatinase and nuclease, but adherence to host cells and the ability to produce haemolysins, lipases and proteases varied from one isolate to another. Of the antibiotics tested, 100% of isolates were susceptible to aztreonam, 98% to ceftazidime and 93% to cefepime. In contrast, high resistance was observed with ampicillin (98%), amoxicillin-clavulanic acid (93%) and cefalotin (62%). These characteristics reveal the potentially pathogenic status of the isolates, which could constitute a threat to human beings.

Aeromonas, potential virulence; antibiotic resistance