Phylogenetic characterization of Salmonella enterica from pig production and humans in Thailand and Laos border provinces

BACKGROUND AND AIM: The genetic relationship among serotypes of Salmonella enterica from food animals, food of animal origin, and human is of interest as the data could provide an important clue for the source of human infection. This study aimed to determine the genetic relatedness of S. enterica from pig production and human in Thailand–Laos border provinces. MATERIALS AND METHODS: A total of 195 S. enterica serotypes isolated from pig and pork (n=178) and human (n=17) including four serotypes (Typhimurium, Rissen, Derby, and Stanley) were randomly selected to examine their genetic relatedness using highly conserved sequence of three genes (fim A, man B, and mdh). RESULTS: The results showed that 195 Salmonella isolates of four different serotypes were grouped into five different clusters, and members of the same Salmonella serotypes were found in the same cluster. Salmonella isolated from pig production and human in Thailand–Laos border provinces represented overlapping population and revealed a high degree of similarity, indicating close genetic relationship among the isolates. CONCLUSION: The results support that the determination of Salmonella serotyping combined with analysis of phylogenetic tree can be used track the clonal evolution and genetic diversity of Salmonella serotypes in different host species.