Occurrence and Antimicrobial Susceptibility Profiles of Multidrug-Resistant Aeromonads Isolated from Freshwater Ornamental Fish in Chiang Mai Province

Abstract

Antimicrobials are commonly used to prevent and treat disease in the ornamental fish industry. However, the indiscriminate and comprehensive overuse of unregulated antimicrobials without appropriate diagnostic examination could contribute to the development of antimicrobial-resistant strains of bacterial pathogens. Moreover, human infections caused by pathogens transmitted from fish or the aquatic environment are quite common. The frequent detection of antimicrobial resistance in ornamental fish and their environments are inevitable so as to decrease the transfer of antimicrobial-resistant bacteria from aquatic sources to other environments. This study evaluated the prevalence of common bacteria species and the antimicrobial susceptibility profile in ornamental fish that were sold in an ornamental fish shop in Chiang Mai, Thailand. Aeromonas spp. were the most dominant of the isolated species from the ornamental fish samples and accounted for 68.09% of the total. Other species detected included Vibrio spp., Pseudomonas spp., and Citrobacter spp. A high percentage of resistance to amoxicillin (93.75%), oxytetracycline (79.69%), and erythromycin (75.00%) was observed among the Aeromonas spp. The antimicrobial resistance information for ornamental fish is very limited, and the results from this study indicate that the Aeromonas spp. are highly resistant to several important antibiotics. The results suggest that additional steps should be taken to educate store owners to reduce the indiscriminate use of these antibiotics to decrease the antimicrobial resistance in ornamental fish to potentially improve public health.

Characterization and Antimicrobial Resistance of Environmental and Clinical Aeromonas Species Isolated from Fresh Water Ornamental Fish and Associated Farming Environment in Sri Lanka

“…In our study, members of the genus Aeromonas comprised the majority among Gramnegative bacterial isolates (data not shown) from fish and their associated environment, in agreement with previous observations [7,49].…”

“…Members of the genus Aeromonas are considered autochthonous in aquatic environments [1,45]. They have been frequently isolated from fresh water ornamental fish farming environments including in water, in sediment [46][47][48] and in apparently healthy and diseased fish [1,7,44]. The wide distribution of aeromonads in ornamental fish farming environment highlights their ability to serve as opportunistic pathogens in fish and also indicates their possible interactions with humans via direct contact or environmental contamination.…”

“…Mesophilic Aeromonas species have been linked to major disease outbreaks, leading to a high mortality in cultured freshwater food fish and ornamental fish [4][5][6], resulting in huge economic losses around the globe over the past two decades. Among mesophilic aeromonads, A. hydrophila, A. caviae, A. sobria, and A. veronii have been associated with MAS in a number of economically important fish [5,7]. Aeromonas is also an emerging pathogen of humans, and may cause a wide spectrum of intestinal and extra-intestinal diseases.…”

“…Ornamental fish keeping has become a popular hobby among many people and more than 100 countries in the world are involved in the global ornamental fish trade [7]. The ornamental fish industry in Sri Lanka has expanded to be a large business over the past three decades.…”

The Role of Aquatic Ecosystems (River Tua, Portugal) as Reservoirs of Multidrug-Resistant Aeromonas spp.

“…Although the Aeromonas genus is autochthonous in the aquatic environment, and easy to detect in any water type, they have received increasing attention as opportunistic pathogens [2,[35][36][37]. Aeromonas spp.…”