Q. Define Clostridium perfringens-associated gastroenteritis?

Clostridium perfringens-associated gastroenteritis is a food borne disease which is frequently reported and is a common cause of illness. The organism Clostridium perfringens is a large (2-8 pm long; 1 pm wide), non-motile, gram positive, obligate anaerobe and spore-forming rod as can be seen in Figure 5.10. The organism does not produce spores while growing in the food but it forms spores when it reaches the intestinal tract.

The spores of C. perfringens can withstand boiling temperatures for up to 6 hours. The optimum temperature for growth is between 43°C to 45"C, whereas, the maximal temperature at which it can grow is 55°C. Its growth gets restricted at the temperatures of about 15-20°C. The vegetative cells of the organism are usually destroyed at the temperatures of 60°C and above.

The strains of C. perfringens are classified into 5 types-A to E, depending on the type of toxin produced. The strains of C. perfringens type A, the spores of which are heat resistant survive at temperatures from 95-100°C for periods of upto one hour. These are responsible for several outbreaks in the United Kingdom. The incubation period for the disease ranges between 8 to 22 hours, but normally the symptoms occur between 8 to 12 hours after the ingestion of contaminated food. The important symptoms are severe abdominal cramps and watery diarrhoea, vomiting is rare. The recovery is usually within 1' or 2 days.