Salmonella detection in Brown Rats (Rattus norvegicus) and Seasonal Variations: a case study in Gorgan, North-East of Iran

International Journal of Molecular and Clinical Microbiology

دوره 14، شماره 2، اسفند 2024، صفحه 2114-2121   

نوع مقاله: Research Article

شناسه دیجیتال (DOI): 10.22034/ijmcm.2025.710237

نویسندگان

somyeh Namroodi^{* 1}؛ Nazanin Nikroo¹؛ Hesameddin Akbarein²؛ MohammadKazem Koohi³

¹Department of Environmental sciences, Faculty of fisheries and environmental sciences, Gorgan University of Agricultural Sciences & Natural Resources, Gorgan- Iran

²Division of Epidemiology & Zoonoses, Department of Food hygiene and quality control, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.

³Division of Toxicology, Department of Comparative Bioscience, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.

چکیده

Salmonella is a Gram-negative bacterium that causes disease in both warm- and cold-blooded animals, exhibiting sensitivity to dryness and high temperature. Urban rodents act as asymptomatic reservoirs of Salmonella, posing a significant public health risk, especially to children and immunocompromised individuals. Gorgan, the capital of Golestan Province in northeastern Iran, is characterized by a dense population of brown rats. The city was divided into 20 districts, and five rats from each district were systematically captured using handmade traps during all four seasons. Fecal samples were analyzed using both conventional culture techniques and molecular diagnostic assays. Salmonella was detected in 24% of the sampled rats (24 out of 100). Two clinically relevant serotypes—S. Typhimurium (n=17) and S. Enteritidis (n=7)—were identified. No statistically significant association was observed between infection rates and the rodents’ age or sex. A distinct seasonal trend in prevalence was observed, with contamination rates of 36% in spring, 28% in summer, 20% in autumn, and 12% in winter. The tow detected serotypes frequently implicated in human salmonellosis. Given the zoonotic potential of Salmonella, these findings emphasize the need for minimizing the risk of bacterial transmission from rodents to humans, improving urban public health and enhanced urban health measures, including effective waste disposal, modernization of sewage systems, and robust rodent control programs. The observed seasonal fluctuation emphasizes the need for year-round monitoring and targeted interventions during high-risk periods for application of better disease management strategies.

کلیدواژه‌ها

Zoonoses؛ Feces؛ age؛ sex