Serotyping of Salmonella Enterica Isolated from Mice Caught on US Poultry Farms 1995 through 1998

: In this study, a collection of Salmonella enterica subspecies obtained from live mice caught on 32 poultry farms in the Northeast US between 1995 to 1998 was evaluated to provide a historical reference for serotype distribution during a time when egg contamination by serotype Enteritidis was at its peak. Of 821 mice cultured, 157 were positive (19.1%). Seven mice harbored two serotypes of Salmonella. Nine serotypes were detected, eight of which are often associated with foodborne illness. The three most prevalent serotypes were Enteritidis, Heidelberg, and Typhimurium. Enteritidis and Typhimurium were obtained from both spleens and intestines without preference according to type of sample. In contrast, Heidelberg was isolated most often from intestines and Schwarzengrund was most often obtained from spleens. These results support that the house mouse Mus musculus was a risk factor for introduction of multiple pathogenic Salmonella serotypes in poultry raised in the Northeast US during the mid-1990s. Isolates were submitted to the Food and Drug Administration and draft genomes for 64 isolates of Salmonella enterica serovar Enteritidis data have been released through the National Center for Biotechnology Information via the GenomeTrakr network.