Exploring Multidrug Resistant and Possible Extensively Drug Resistant Extended-Spectrum Β-Lactamase-Producing Escherichia coli Isolated from Frozen Chicken Meat in Bangladesh

Multidrug resistant extended-spectrum β-lactamase (ESBL)-producing Escherichia coli is considered a serious concern to public health worldwide including Bangladesh, and chicken meat is recognized as an important reservoir of ESBL-Ec dissemination to humans. Therefore, this study aimed to determine the prevalence, and phenotypic and genotypic antimicrobial resistance pattern of ESBL-producing Escherichia coli (ESBL-Ec) in frozen chicken meat. A total of 113 frozen chicken meat samples were purchased from 40 outlets of 9 branded supershops in five megacities in Bangladesh. Isolation and identification of Escherichia coli were done based on cultural, biochemical properties and PCR assay. The resistance pattern was determined by disk diffusion method. ESBL-encoding genes were determined by multiplex PCR. The results showed that 76.1% samples were positive for Escherichia coli, of which 86% were ESBL producers. All the isolates were multidrug-resistant (MDR). Resistance to 9–11 and 12–13 antimicrobial classes was observed in 38.4% and 17.4% isolates, respectively while only 11.6% were resistant to 3–5 classes. The possible extensively drug resistance (pXDR) was found in 2.3% isolates. The high single resistance was observed for oxytetracycline (93%) and amoxicillin (91.9%), followed by ampicillin (89.5%), trimethoprim-sulphamethoxazole and pefloxacin (88.4%), and tetracycline (84.9%). Most importantly, 89.6% of isolates were resistant to carbapenems. All the isolates were positive for blaTEM gene. However, the blaSHV and blaCTX-M-2 genes were identified in two ESBL-non producer isolates. None of the isolates were carried blaCTX-M-1 gene. This study provided evidence of wide dissemination of MDR and existence of pXDR ESBL-Ec in frozen chicken meat in Bangladesh. Our data clearly indicated that frozen chicken meat is, at the present time, the most significant known food source of ESBL-Ec to which peoples are regularly exposed.