The genetic relatedness between Salmonella enterica isolated from food samples and outpatient’s clinics using pulsed field gel electrophoresis

Abstract

Background and objectivesSalmonella enterica (S. enterica) is an important food-borne pathogen that causes many public health problems, molecular characterizations and fingerprinting of the recovered strain are very important for epidemiological surveillance. Therefore, food of animal origins collected from various marketplaces located in Riyadh, KSA, were tested to evaluate the incidence, molecular characterizations, and fingerprinting of Salmonella species using multiplex-PCR and Pulsed-Field Gel Electrophoresis (PFGE). MethodsThree hundred and fifty food samples (125 minced poultry meat, 110 ground beef meat, and 115 hamburgers beef meat) were collected from markets placed in Riyadh, KSA, from the period of June 2019 to October 2019. Also, 25 strains of Salmonella species isolated from humans who suffer from food poisoning and gastrointestinal disturbance were collected from hospitalized patients situated in Riyadh from the period of May 2019 to October 2019. Typical bacteriological practices for culturing and identification of Salmonella from the collected food samples, as well as molecular detection and characterizations using multiplex-PCR and fingerprinting of the recovered Salmonellae species using PFGE were carried out. ResultsThirty-seven strains of S. enterica subspecies (10.57%) were isolated, mostly from chicken samples 19 (15.2%). Identical chromosomal restriction patterns had been observed between the strains of Salmonella Typhimurium recovered from food of animal origins and the strains recovered from outpatients’ clinics. ConclusionsThe study concluded that chickens are the main natural reservoir host of Salmonella infection for human being as the genetic similarity and the degree of relatedness between the recovered strains of S. enterica from food samples and from outpatients clinics using PFGE revealed a high degree of identity (similarity index up to 99%). Therefore the regulations for handling chicken products should be updated to reduce Salmonella infections.