Antibiotic resistance is a serious worldwide problem threatening human health and life.
Poultry, especially broilers, represent a major source of ESBL-producing E. coli due to the
extensive use of antibiotics during their production. This study investigated the prevalence
of ESBL-EC in broilers, the surrounding environment, and humans, as well as the
occurrence of ESBLs, carbapenemases, and blaCMY2 genes. 249 samples were included in
that study: 130 broiler cloacal swabs, 54 environmental samples, and 65 human samples.
All samples were grown on Macconkey broth, then cultured on EMB containing cefotaxime
sodium. Suspected E. coli isolates were identified and confirmed biochemically by IMVIC
tests. The disc diffusion method was used to determine the antibiotic susceptibility pattern
of E. coli isolates grown on EMB with cefotaxime. PCR was performed for the amplification
of ESBLs, carbapenemases, and blaCMY2 genes. Our results revealed that ESBL-EC was
isolated from 180 (72.3%) of the 249 collected samples. The prevalence of ESBL-producing
E. coli was as follows: 85.4%, 46.3%, and 67.7% in broiler cloacal swabs, environmental
samples, and human samples, respectively. Among 188 E. coli isolates grown on EMB
containing cefotaxime, 187 were resistant to CTX, 170 to CAZ, 166 to FEP, and 146 to FOX.
PCR amplification showed that the predominant gene was blaTEM, which was detected in
98% of the amplified isolates, followed by blaCTX-M (88%). BlaKPC wasn't detected in any
isolates. Many gene combinations were detected, and the most common one was blaTEM
with blaCTX-M, which was detected in 24 (48%) of the 50 isolates.