Diversity and profiles of resistance to antibiotics in species of Aeromonas isolated from the aquatic ecosystem of ecuador

Introduction: In Ecuador, the diversity of Aeromonas species and their resistance profiles to antibiotics in most aquatic ecosystems are unknown. Objective: To know the diversity of species of the genus Aeromonas and their resistance profiles to antibiotics present in the mineralmedicinal water spa “Santagua de Chachimbiro” and in the water of the Cuicocha crater volcanic lake. Methodology: Water samples from the “Santagua de Chachimbiro” spa and from the volcanic crater lake Cuicocha, located in the province of Imbabura-Ecuador, were analyzed. The isolation of the Aeromonas species was carried out by the deep seeding technique and by membrane filtration using R2A agar and ampicillin starch agar as the culture medium. The bacteria were identified following the schemes proposed by Longa et al., (1997), complemented with tests of the Microgen galleries. The antibiotic resistance profile was determined by the plate diffusion method of Kirby and Bauer (1966) interpreted according to the CLSI (2019). Results: A total of 19 strains of the genus Aeromonas belonging to 6 species were identified. Antibiotic resistance profiles show different patterns for each of the species, although species multi-resistant to antibiotics amoxicillin, amoxicillin/clavulanic acid, aztreonam, erythromycin and tetracycline prevail. Conclusions: The presence of various species of Aeromonas in aquatic environments of Ecuador with varied profiles of resistance and multi-resistance to antibiotics is demonstrated. Keywords: aeromonas; aquatic ecosystem; mineralmedicinal water; crateric lake; resistance to antibiotics