Salmonella serovars in sheep and goats and their probable zoonotic potential to humans in Suez Canal Area, Egypt

Abstract

Background Salmonella is one of the most common and economically important zoonotic pathogens. This study aimed to determine the occurrence of Salmonella serovars in sheep and goats and their probable zoonotic risk to humans in Suez Canal area in Egypt. A total of 320 fecal samples from sheep (n = 120), goats (n = 100), and humans (n = 100) were collected and examined for the presence of Salmonella based on cultural and biochemical characteristics, and serological analysis. Moreover, the virulence of the identified Salmonella isolates was assessed by molecular screening for invA, stn, spvC, and sopB virulence genes using PCR. Results Overall, the occurrence of Salmonella in sheep feces (23.3%) was higher than that in goat feces (7%) and human stool (13%) in the study area. The identified isolates belonged to 12 serotypes; ten, five, and eight from sheep, goats, and humans, respectively. The most frequently identified serotypes were S. Typhimurium from sheep feces, and S. Enteritidis from both goat feces and human stool, with four serotypes; S. Typhimurium, S. Enteritidis, S. Dublin and S. Saintpaul, were mutually shared between all of them. Demographic data revealed that diarrheic sheep (85.7%) and goats (25%) had a higher risk for Salmonella fecal carriage than non-diarrheic ones (19.5% and 6.25%, respectively). The prevalence of Salmonella infection in humans in contact with sheep and goats (28%) was significantly higher than its prevalence in people having a history of contact with animals other than sheep and goats (10%) and those having no history of animal contact (7.3%) (χ2 = 6.728, P ˂ 0.05). The stn, spvC, and sopB genes were detected in 98.1% of the isolates, with a significant, very strong positive correlation for their mutual presence (P < 0.05). Approximately 40.7% of isolates that carried the invA gene had a non-significant, very weak positive correlation with other virulence genes. The most common genotypic virulence profile for all isolates was stn, spvC, and sopB; however, invA, stn, spvC, and sopB was the frequent virulotype for S. Typhimurium, S. Tsevie, S. Apeyeme, and S. Infantis. Conclusions The present study highlights the role of apparently healthy and diarrheic sheep and goats as reservoirs and sources of human infection with virulent Salmonella serovars in the Suez Canal area.

Zoonotic Disease Risks of Live Export of Cattle and Sheep, with a Focus on Australian Shipments to Asia and the Middle East

“…A major cause of disease in sheep travelling from Australia to the Middle East is salmonellosis, which may be transmitted to humans handling the animals, either on board or on arrival [ 92 ]. This gastrointestinal infection is exacerbated by the stress of transport [ 60 ], particularly if sheep become inappetent during the journey from Australia to the Middle East [ 91 ].…”

Development and Evaluation of a Multiplex Fluorescence PCR for Salmonella Virulence Genes Analysis

“…The ssaR and sifA genes are essential for the intracellular survival and subsequent replication of Salmonella (5)(6)(7), while the pefA, sipA, fimA, sopE2, sopB, and prgH genes are involved in adhesion and invasion of host cells (7)(8)(9)(10). The spvC gene can suppress the innate immunity of infected hosts (11), and the stn gene is implicated in the complex mechanisms of diarrhea (12). Additionally, virulence genes can be transferred from one strain to another, enhancing the pathogenicity of Salmonella strains and potentially leading to disease outbreaks.…”

Investigation of Salmonella spp. and Escherichia coli in the Snake-eyed lizard ( Ophisops elegans) (Sauria, Lacertidae) in the Çankırı Province of Turkey

“…and Escherichia coli are bacteria capable of colonizing the gut of various animals, and thus may threaten human and animal health. These bacterial pathogens have been isolated and identified from multiple avian and mammalian species that serve as their host (Şahan et al 2016, Gambi et al 2022, Hawwas et al 2022, Babacan 2023. While the presence of S. enterica serovars is frequently associated with diseases, E. coli serovars are generally accepted as commensal organisms (Lupolova et al 2017).…”