Detection of Zoonotic Antibiotic Resistant Salmonella spp. Carrying Virulence Genes in Rural Mus musculus, Golestan Province, North of Iran

Document Type: Original Article

Author

Department of Environmental sciences, Faculty of fisheries and environmental Sciences, Gorgan University of Agricultural Sciences & Natural Resources, Gorgan, Iran

Abstract

Background and aims: Salmonella spp. infect cold-blooded and warm-blooded animals and may
cause a worldwide zoonotic disease, salmonellosis, in infected animals. Rodents can be Salmonella
carriers without any signs of salmonellosis. The frequency of salmonella contamination, the presence of
virulence genes (SpvR and SpvB) and antibiotic resistance pattern of isolated Salmonella were studied
in rural Mus musculus to reveal the possible role of them in Salmonella dissemination in Golestan
province.
Methods: A total of 190 wet rectal swabs of M. musculus were obtained from rural areas of Golestan
province with different climate conditions. The swabs were cultured and positive samples were
serotyped and their antibiotic resistance patterns were studied. The presence of Salmonella and
virulence genes was analyzed by SpvR and SpvB genes primers, respectively.
Results: Salmonella spp. were detected in 15 (7%) of 190 fecal samples by bacterial culture and PCR.
S. enteritidis (n=9) and S. typhimurium (n=6) were identified. The highest and lowest frequencies were
detected in humid (13.1%) and arid areas (3.1%), respectively. SpvR and SpvB genes were diagnosed
in 10 of 15 (66.6%) isolated Salmonella. The highest resistance of detected Salmonella spp. was
observed against streptomycin (53%). All the isolates were sensitive to chloramphenicol, gentamicin
and trimethoprim.
Conclusion: The Salmonella contamination in sampled house mice indicates that native people should
be made aware of the risk of Salmonella infection and possible ways of salmonella transmission through
rodents. In addition, the application of appropriate therapeutic approaches to prevent the spread of
antibiotic resistant Salmonella is recommended.

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