[Production of enterotoxins A, B and C in staphylococcal strains isolated from animal food products and other sources].

Studies were carried out on the production of enterotoxins A, B, and C by a total of 654 strains of Staphylococcus aureus. Of these, 326 were isolated from food products of animal origin (and had no connection with intoxications); 190 were isolated from personnel working in the food industry; and 138 were isolated from milk animals, containers, and equipment at productional enterprises. Thirty strains of S. epidermidis, isolated from food products and workers were likewise tested for the production of the same enterotoxins. The enterotoxins were obtained by the modified method of Hallander, and their demonstration was performed by a variant technique of the double gel diffusion test after Ouchterlony. It was found that the Staphylococcus aureus strains isolated from food products produced enterotoxins in 12.3 per cent of the cases; was found in 6.1% of the strains, C--in 3.1%, and B--in 2.5%. Types A and C were found simultaneously in 0.6% of the strains. Enterotoxins were found in 16.6% of the strains isolated from workers and in 1.7% of those isolated from the udder of cows. The incidence of toxin production and the relative share of the three types of enterotoxins depended on the origin of staphylococci and their capacity to produce them in amounts that could be demonstrated by the methods employed. Under optimal conditions the amounts varied: for strains that produced type A they ranged from 1 to 20 micrograms/cm3; for those that produced type B they were from 1 up to 100 micrograms/cm3; and for those that produced type C they were from 1 to 40 micrograms/cm3. No production of enterotoxins A, B, and C was established with S. epidermidis strains.