Prevalence and genetic properties of Salmonella enterica serovar Typhimurium definitive phage type 104 isolated from Rattus norvegicus and Rattus rattus house rats in Yokohama City, Japan

The prevalence and genetic properties of Salmonella enterica serovar Typhimurium definitive phage type 104 (DT104) strains among serovar Typhimurium isolates from house rats are investigated by studying antimicrobial resistance, detection of class I integrons and antimicrobial resistance genes. The results have shown that DT104 strains are dominant in house rat colonies in each building and have suggested that house rats might play an important role in the epidemiology of DT104.