Campylobacter bacteria are easily killed by thorough cooking, therefore the risk lies in the consumption of raw foods or cooked foods which have been contaminated either as a result of poor handling or the use of dirty utensils. Clostridium perfringens is a type of food poisoning organism often associated with large scale catering, such as canteens, schools and hospitals. It may be found in the bowels of animals, birds and man, and in such a habitat it spores readily. Spores will survive in soil or dust for a very long time and if the vegetation or water sources are contaminated, infection of food animals is likely. Contaminated products may result in human infection.
Soil adhering to vegetables is another potential source in food preparation areas.
Very large numbers of this organism are required to cause human illness. This type of food poisoning is often associated with reheated meat and meat products. Since the organism is only able to multiply in the absence of air, it thrives at the bottom of a stock pot or in the centre of a meat pie or rolled joint. Most outbreaks normally involve a large number of people because Clostridium perfringens is more commonly found in foods that have been prepared in bulk. The symptoms include stomach pains and diarrhoea and usually last for 12-24 hours.