Phenotypic and Genotypic Eligible Methods for Salmonella Typhimurium Source Tracking

Abstract

Salmonellosis is one of the most common causes of foodborne infection and a leading cause of human gastroenteritis. Throughout the last decade, Salmonella enterica serotype Typhimurium (ST) has shown an increase report with the simultaneous emergence of multidrug-resistant isolates, as phage type DT104. Therefore, to successfully control this microorganism, it is important to attribute salmonellosis to the exact source. Studies of Salmonella source attribution have been performed to determine the main food/food-production animals involved, toward which, control efforts should be correctly directed. Hence, the election of a ST subtyping method depends on the particular problem that efforts must be directed, the resources and the data available. Generally, before choosing a molecular subtyping, phenotyping approaches such as serotyping, phage typing, and antimicrobial resistance profiling are implemented as a screening of an investigation, and the results are computed using frequency-matching models (i.e., Dutch, Hald and Asymmetric Island models). Actually, due to the advancement of molecular tools as PFGE, MLVA, MLST, CRISPR, and WGS more precise results have been obtained, but even with these technologies, there are still gaps to be elucidated. To address this issue, an important question needs to be answered: what are the currently suitable subtyping methods to source attribute ST. This review presents the most frequently applied subtyping methods used to characterize ST, analyses the major available microbial subtyping attribution models and ponders the use of conventional phenotyping methods, as well as, the most applied genotypic tools in the context of their potential applicability to investigates ST source tracking.

Worldwide Epidemiology ofSalmonellaSerovars in Animal-Based Foods: a Meta-analysis

“…It is not surprising that the isolation of this serovar in outbreaks is strongly linked to the pork matrix. Additionally, as reported by Ferrari et al (77), currently several studies have demonstrated correlations between swine and human S. Typhimurium isolates.…”

Persistent Infection and Long-Term Carriage of Typhoidal and Nontyphoidal Salmonellae

“…Such molecular typing approaches include pulsed-field gel electrophoresis (PFGE) (101, 102); multilocus sequence typing (MLST), which is based on variation in the sequences of seven housekeeping gene fragments (103,104); ribotyping (105); clustered regularly interspaced short palindromic repeat (CRISPR) typing (106,107); as well as other molecular methods. Since several comprehensive reviews about molecular Salmonella typing approaches have been published in the last few years (108)(109)(110)(111), and because more-modern next-generation sequencing methods are now emerging (see below), which are expected to replace these techniques in the near future, I do not further discuss these techniques here.…”

Characteristics of microbial communities and intestinal pathogenic bacteria for migrated Larus ridibundus in southwest China

“…PFGE was used to analyze the important isolated strains (diarrheogenic E. coli, Salmonella and Yersinia enterocolitica) from L. ridibundus. The procedures were performed according to the protocols of each bacteria published by PulseNet (Curran et al, 2017;Ferrari, Panzenhagen, & Conte-Junior, 2017;Liang et al, 2014). The plugs digested with different enzymes, and electrophoresed with a recommendatory pulse times and hours at 20 V. For data analysis, *.tiff images of the gels were imported into the database of PFGE patterns.…”