Prevalence of Extended-Spectrum-beta-Lactamase-Producing Escherichia coli in Imported Frozen Freshwater Fish in Eastern Province of Saudi Arabia

Background: The prevalence of extended-spectrum beta-lactamase (ESBL) production and antimicrobial susceptibility testing in the Escherichia coli in frozen freshwater fish imported into Saudi Arabia have not been investigated. Objective: The aim of this study was to investigate the prevalence of ESBL-producing E. coli in frozen freshwater fish imported into Saudi Arabia and retailed in various supermarkets and food stores in the Eastern Province of Saudi Arabia. Materials and Methods: A total of 405 imported freshwater fish samples: Catfish (n = 65); mrigal (n = 45); tilapia (n = 135); carfoo (n = 50); rohu (n = 75); and milkfish (n = 35) were purchased from supermarkets and screened for ESBL-producing E. coli using ESBL chromogenic selective agar. The phenotypically confirmed ESBL isolates were further tested for antimicrobial susceptibility testing against 21 antimicrobial agents and amplification of bla(TEM), bla(SHV), and bla(CTX-M) genes using polymerase chain reaction. Results: A total of 110 out of the 405 (27.2%) freshwater fish samples were found to be positive for ESBL producing E. coli and yielded 224 confirmed isolates. The highest rates of multi-drug resistant patterns to antimicrobial agents were observed in E. coli isolated from catfish, mrigal, and tilapia imported from Thailand and milkfish imported from Vietnam. The most prevalent ESBL gene found in the samples was bla(CTX-M), which was detected in tilapia (100%, n = 30) imported from Thailand and carfoo (100%, n = 5), milkfish (60%, n = 24), catfish (52.3%, n = 34), and tilapia imported from India (34.8%, n = 24). Conclusion: The results confirmed the imported frozen freshwater fish is pool reservoir of antibiotic resistance and ESBL producing E. coli.