Contamination of Japanese Retail Foods With Enterotoxigenic Clostridium Perfringens Spores

The contamination of Japanese retail foods and the intestinal contents of animals with the spores of enterotoxigenic Clostridium perfringens were investigated by analyzing clostridial toxin genes (cpa and cpe) using a culture method and PCR. Enterotoxigenic C. perfringens was detected in 12.3% (8/65 samples) of shellfishes, 8.4% (7/83 samples) of dried seafoods, 7.4% (15/204 samples) of curry mixes and spices, 2.6% (1/39 samples) of dried seaweeds, 2.5% (2/79 samples) of fishes and shrimp, 1.9% (2/105 samples) of chicken, and 0.8% (1/121 samples) of root vegetables. Enterotoxigenic C. perfringens was not detected in beef (95 samples) and pork (110 samples). The ratio of enterotoxigenic C. perfringens-positive to all C. perfringens-positive samples was high for fish and shrimp (40.0%), curry mixes and spices (19.0%), shellfish (18.1%), dried seafood (16.7%), and dried seaweed (16.7%). Although C. perfringens was investigated in the intestinal contents of cattle (212 samples), pigs (207 samples), and chicken (159 samples), enterotoxigenic C. perfringens was not detected. These results indicate that beef and pork sold in Japan are unlikely to be contaminated with enterotoxigenic C. perfringens, and that other foods such as curry powder, shellfish, and dried seafoods are more important as the sources of contamination in Japan. Dried seafoods are frequently used to make soup stock in Japanese and other Asian dishes. In cases of food-borne illness linked to C. perfringens contamination of Japanese and Asian dishes, dried seafood should be investigated, in addition to other ingredients such as meat.