Molecular characterization of enterohemorrhagic isolated from diarrhea samples from human, livestock, and ground beef in North Jordan.

Background And Aim: Enterohemorrhagic (EHEC) is an important foodborne pathogen with worldwide distribution. Data regarding its presence, distribution, virulence, and antimicrobial susceptibility among various animal species and humans in Jordan are lacking. Therefore, the objectives of this study were to isolate and characterize EHEC from human and animal diarrhea fecal samples and ground beef samples.

Materials And Methods: A total of 100 and 270 diarrhea fecal samples from humans and animals, respectively, were collected. In addition, 40 ground beef meat samples were collected from retail markets. EHEC was positively identified by detecting Shiga toxins ( and ) genes using multiplex polymerase chain reaction (PCR). Antimicrobial susceptibility patterns were determined using the disk diffusion test. Beta-lactamase production was detected using the double disk diffusion test and the extended-spectrum beta-lactamases (ESBLs) were identified by detection of , , and genes using multiplex PCR. Pulsed-field gel electrophoresis (PFGE) was used to investigate the relatedness of EHEC isolates from different sources.

Results: Out of 410 samples, 194 isolates were positively identified, of which 57 isolates (29%) were classified as EHEC. Thirty-five (61%) of EHEC isolates were serotyped as O157 (19: O157:H7 and 16: O157:NM). The gene was detected only among the sheep and goats isolates at a rate of 7.6% and 5.2%, respectively, while the gene was detected in only one ground beef meat sample. EHEC isolates showed high resistance patterns against amoxicillin, gentamycin, cephalexin, and doxycycline. Twenty-four out of 32 EHEC isolates were determined as ESBL producers, among which 14 isolates expressed the gene and 19 isolates expressed the while four expressed both genes. PFGE analysis revealed two clusters with high similarity (92%) originated from ground beef meat and cattle fecal samples. No similarities were found between human and animal isolates.

Conclusion: Results of this study indicate widespread ESBL EHEC among humans, animals, and ground beef meat samples. These results represent an important alarm that requires the implementation of appropriate preventative measures by both human and animal health sectors to prevent the transmission of this important foodborne pathogen.