Active perfringocin typing of food poisoning strains of Clostridium perfringens type A--a new tool for epidemiological investigations.

Active perfringocin typing, as an epidemiological tool, for investigation into food poisoning outbreaks due to C. perfringens type A has been developed. Ninety strains included in this study were from England, America, India, Japan, France and Canada Nine indicator strains exhibiting different patterns of inhibition were selected for perfringocin typing. With these indicator strains, 81.11 per cent of the strains were typable into ten perfringocin types. Type "a" and "b" alone could type 47.92 per cent of the strains. Type "f" was predominantly found to be for the American strains and "b" and "c" for the Indian strains. Active perfringocin typing developed for the first time for the food poisoning strains of C. perfringens type A was expected to prove useful in the epidemiological investigations.