Prevalence of the blaCTX-M and blaTEM genes among extended-spectrum beta lactamase-producing Escherichia coli isolated from broiler chickens in Indonesia

Introduction: Infections of humans and animals by multidrug resistant bacteria are increasing because of the inappropriate use of antibiotics. Disease management may be more challenging if Escherichia coli produce extended-spectrum beta-lactamase (ESBL), which could cause resistance to aztreonam and third-generation cephalosporins. This study was aimed at determining the prevalence of the bla(CTX-M) and bla(TEM) genes among ESBL-producing E. coli isolated from broiler chickens in Indonesia. Material and Methods: A total of 115 broiler cloacal swab samples were obtained from 22 farms and studied for the presence of E. coli. The isolates were identified using approved standard methods and were purified on eosin methylene blue agar media. The E. coli isolates were subjected to sensitivity testing using beta-lactam antibiotics, and ESBL production was confirmed by a double-disc synergy test. The presence of the bla(CTX-M) and bla(TEM) genes was identified using a PCR. Results: It was found that 99/115 (86.1%) of the isolated E. coli were resistant to beta-lactam antibiotics and 34/115 (29.6%) of them were phenotypically detected to be ESBL producers. Of the 34 isolates that were confirmed ESBL producers, 32/34 (94.1%) of them harboured the bla(CTX-M) and 13/34 (38.2%) the bla(TEM) genes. The bla(CTX-M) and bla(TEM) genes were detected together in 12/34 (35.3%) isolates. Conclusion: This study discovered that broiler chickens are possible reservoirs of ESBL-producing E. coli that may infect humans. Thus, a committed public health education campaign is recommended in order to mitigate the potential threat to human health.