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Chapter 27
Foodborne toxico-infections
introduction
The pathogenesis and disease symptoms of several pathogens associated with foodborne and
waterborne gastroenteritis are somewhat different from classical food poisoning or foodborne
infection caused by the pathogens described in Chapters 25 and 26. Although the differences are
not always very clear, in this chapter, the gastroenteritis caused by Clostridium perfringens, Bacillus
cereus, Vibrio cholerae, and enterotoxigenic Escherichia coli is described as a toxico-infection. The
first two are Gram-positive spore-formers, and the last two are gram-negative short rods. For each
pathogen, importance, characteristics, nature of toxins, food association, and control measures are
discussed. For some, detection methods and analysis of outbreaks are also included. The following
are some characteristics of foodborne toxico-infection:
1. For spore-formers, ingestion of large numbers of live vegetative cells is usually necessary.
2. Vegetative cells of spore-formers do not multiply in the digestive tract but sporulate and
release toxins.
3. For gram-negative bacteria, live cells can be ingested in moderate numbers.
4. Gram-negative cells rapidly multiply in the digestive tract.
5. Many cells also die, releasing toxins.
6. Toxins of both groups produce the gastroenteritis symptoms.
Clostridium perfringens 1
Importance
Clostridium perfringens causes various disease in humans, animals, and birds, including necrotic
enteritis, gangrene in animals and humans, and food poisoning or gastroenteritis in humans.
Gastroenteritis caused by Clo. perfringens has several specific characteristics. In most outbreaks,
large numbers of cases are involved. In the United States, in the 1960s and 1970s, it was involved
Chapter 27
Foodborne toxico-infections
introduction
The pathogenesis and disease symptoms of several pathogens associated with foodborne and
waterborne gastroenteritis are somewhat different from classical food poisoning or foodborne
infection caused by the pathogens described in Chapters 25 and 26. Although the differences are
not always very clear, in this chapter, the gastroenteritis caused by Clostridium perfringens, Bacillus
cereus, Vibrio cholerae, and enterotoxigenic Escherichia coli is described as a toxico-infection. The
first two are Gram-positive spore-formers, and the last two are gram-negative short rods. For each
pathogen, importance, characteristics, nature of toxins, food association, and control measures are
discussed. For some, detection methods and analysis of outbreaks are also included. The following
are some characteristics of foodborne toxico-infection:
1. For spore-formers, ingestion of large numbers of live vegetative cells is usually necessary.
2. Vegetative cells of spore-formers do not multiply in the digestive tract but sporulate and
release toxins.
3. For gram-negative bacteria, live cells can be ingested in moderate numbers.
4. Gram-negative cells rapidly multiply in the digestive tract.
5. Many cells also die, releasing toxins.
6. Toxins of both groups produce the gastroenteritis symptoms.
Clostridium perfringens 1
Importance
Clostridium perfringens causes various disease in humans, animals, and birds, including necrotic
enteritis, gangrene in animals and humans, and food poisoning or gastroenteritis in humans.
Gastroenteritis caused by Clo. perfringens has several specific characteristics. In most outbreaks,
large numbers of cases are involved. In the United States, in the 1960s and 1970s, it was involved