Abstract

Salmonella is a gram-negative bacterium and has a wide range of hosts, including humans, birds, mammals, and insects. It's one of the most problematic foodborne and zoonotic pathogens. This study aimed to find the relationship between salmonellosis in humans and handling salmonella-infected poultry. For this purpose, 100 fecal samples from infected hens and 16 fecal samples from poultry farm workers suspected of having salmonellosis were collected. Bacterial isolation and identification, virulence factor profiling, and antibiotic profiling were conducted. The results of M-PCR for six virulence factors and the antibiotic sensitivity test for eight antibiotics showed that there was high similarity in the virulence factor profile (Stn, Pef, and sipB genes were in the same rate, 42.8%, 57.1%, and 42.8%, respectively, and the invA, spiA, and orgA genes were close in rate) and the antibiotic profile (chloramphenicol, ciprofloxacin, tetracycline, nitrofurantoin, and trimethoprim were in the same rate, 71.4%, 71.4%, 57.1%, 85.7%, and 71.4%, respectively, and nalidixic acid, cephalexin, and streptomycin were close in rate) of Salmonella enterica subsp. enterica serovar Typhimurium isolated from hens and poultry farm workers. The statistical results showed a significant difference at the probability level (p≤0.05). In conclusion: S. Typhimurium is circulating in both poultry and humans with considerable prevalence, harboring multiple virulence genes and showing alarming multidrug resistance. These findings emphasize the zoonotic risk of S. Typhimurium and highlight the need for surveillance, prudent antibiotic use, and strict biosecurity measures.

Key words: Antimicrobial resistance, Enterica serovar Typhimurium, Poultry, Salmonella enterica subspVirulence genes, Zoonosis