Occurrence of enterotoxigenic Staphylococcus aureus in food.

Gastroenteritis is one of the most frequent microbial diseases, which is caused by the ingestion of food contaminated with staphylococcal enterotoxins. In our study, the production of staphylococcal enterotoxins A, B (SEA, SEB) and the presence of respective staphylococcal enterotoxin genes were investigated in the field S. aureus isolates obtained from foods and food industry manufactures in East Slovakia. Radioimmunoassay (RIA), polymerase chain reaction (PCR) and dot-blot hybridisation were used for examination. The ability to synthesise enterotoxins was found in 20 (39.2%) of the total number of 51 isolates. Production of SEA was recorded in 3 (5.9%), production of SEB in 12 (23.5%) and production SEA together with SEB in 5 (9.8%) staphylococcal isolates. Nine (47.4%) sheep cheese isolates of the total number of 19 produced enterotoxins, especially SEB (36.8%). S. aureus isolates from pasta were enterotoxigenic in 6 cases (33.3%). The synthesis of enterotoxins was not detected in Bryndza cheese and sausages isolates. One enterotoxigenic isolate was obtained from smears of technological equipment and 4 isolates from throat and nasal swabs. No differences in results were recorded between RIA and PCR as well as PCR and dot-blot hybridisation. Our results suggest that it is of special importance to follow the presence of enterotoxigenic S. aureus strains in foodstuffs, especially for protecting the consumers from food poisoning.