Molecular epidemiology of Salmonella enteritidis

Sixteen strains of Salmonella enteritidis isolated in 1991 from 13 unrelated poultry-associated sources, 7 strains from 2 community outbreaks, and 18 human sporadic isolates were investigated by phage typing, analysis of rRNA gene restriction patterns (ribotyping) and plasmid profiles. Four different phage types and 10 SphI patterns were found, whereas plasmids were identical in all but 4 isolates. Only one ribotype (RT A) occurred among both human and avian strains. This particular ribotype was also responsible for the two outbreaks investigated, suggesting that such strains may be of special significance for the increase of S. enteritidis infections.