Distribution of staphylococcal enterotoxin genes among Staphylococcus aureus isolates from poultry and humans with invasive staphylococcal disease

Food poisoning by Staphylococcus aureus affects hundreds of thousands of people each year. Staphylococcus aureus also causes invasive diseases such as arthritis (in poultry) and septicemia (in poultry and humans). Foodborne disease is caused by the ingestion of a staphylococcal enterotoxin (SE). Enterotoxin has also been associated with other S. aureus illnesses in humans and domestic animals. In this study, polymerase chain reaction was used to detect the staphylococcal enterotoxin genes, SEA, SEB, SEC, SED, and SEE, in S. aureus isolates associated with invasive disease in poultry and humans. In the 34 poultry isolates, only one isolate was found to contain a SE gene, sec. In the 41 human isolates, over 51% tested positive for an SE gene with 12.2% positive for the gene for SEA, 2.4% for SEB, 22% for SEC, 24.4% for SED, and 0 for SEE. The disparity between the rates for SE gene(s) in poultry and human isolates suggests a lesser role for the enterotoxins in invasive poultry disease than in human disease.