Clonal relatedness and antimicrobial susceptibility of Salmonella serovars isolated from humans and domestic animals in Iran: a one heath perspective

Document Type : Full paper (Original article)


Department of Pathobiology, Faculty of Veterinary Medicine, Islamic Azad University - Garmsar branch, Garmsar, Iran



Background: Salmonellosis is one of the most important zoonotic diseases in humans and animals worldwide. Aims: The main objective of this study was to report serovars, clonal relatedness, and antimicrobial resistance of Salmonella strains isolated from human, different animal hosts including pigeons, broilers, cattle, camel, parrot, hamster in different regions of Iran. Methods: Twenty-four Salmonella isolates were confirmed at the genus level by biochemical tests and polymerase chain reaction (PCR) by showing the presence of invA gene. Serovars were determined and clonal relatedness was assessed by RAPD-PCR and antibiotic resistance profiles. Results: Overall, Salmonella Typhimurium was the most prevalent serovar (45.8%, 11/24), which was recovered from humans, pigeons, and camel. Salmonella Enteritidis (29.2%, 7/24) was the second common serovar that was recovered from cattle, broilers, human, and hamster. Salmonella Infantis (12.5%, 3/24) belonged only to broiler sources, and Salmonella Seftenberg (12.5%, 3/24) were isolated from eggs and a parrot. The major RAPD pattern was VI (33.3%), in which the two S. Typhimurium (belonged to human and pigeon) exhibited similarity in both RAPD pattern and resistance profile. Antimicrobial susceptibility test showed total resistance to tylosin and erythromycin (100%, 24/24). All isolates (100%, 24/24) were susceptible to ceftriaxone, cefixime, and gentamicin. In total, 75% of the isolates were multi drug resistant (MDR) and revealed 15 different antimicrobial resistance profiles (R-type). Conclusion: This study supports the potential transmission of Salmonella serovars via animal contacts, thus it is necessary to establish a national systematic monitoring program with one health approach for controlling Salmonella infections.


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