Bacillus cereus

This spore forming bacteria is causing an increasing number of cases of food poisoning mainly due to rice from take-away food premises.

The symptoms of Bacillus cereus type food poisoning mimic those of Clostridium perfringens food poisoning. The onset of watery diarrhoea, abdominal cramps, and pain occurs 6 - 15 hours after consumption of contaminated food. Nausea may accompany diarrhoea, but vomiting rarely occurs. Symptoms persist for 24 hours in most instances.

The emetic type of food poisoning is characterised by nausea and vomiting within 0.5 to 6 hours after consumption of contaminated foods. Occasionally, abdominal cramps and / or diarrhoea may also occur. Duration of symptoms is generally less than 24 hours. The symptoms of this type of food poisoning parallel those of Staphylococcus aureus.

Foods incriminated:

A wide variety of foods including meats, milk, vegetables and fish have been associated with the diarrhoea type Bacillus cereus food poisoning. The vomiting type outbreaks have generally been associated with rice products; however, other starchy foods such as potatoe, pasta and cheese products have also been implicated. Food mixtures such as sauces, puddings, soups, casseroles, pastries and salads have frequently been incriminated in food poisoning outbreaks