Clostridium perfringens: characteristics and pathogenesis

Clostridium perfringens or as it is more commonly called C. perfringens, formerly known as C. welchii , is a bacterium which is part of the genus Clostridium. It is a common bacterium which occurs naturally and is subsequently

found all over the world (Ryan). Like many bacteria, it is most often found in decaying matter such as dead plants, animals, and insects. It can also be found in living matter, such as the intestines of infected human beings. In addition, the bacteria can survive in environments with very little oxygen present. Infection from C. perfringens can be very dangerous to people who contract it. It is defined as, "Clostridium perfringens is a pathogenic species of Clostridium that causes a wide range of disease in humans -- from a limited gastroenteritis to a myonecrosis termed gas gangrene" (Nanney). C. perfringens is most often found in ill-cooked food matter or in fecal matter, which then gets passed to food through poor hygiene. If care is given to cook the food materials properly and then to store it hygienically afterwards, then the food product will most likely be safe to eat.

Causes of Infection:

C. perfringens is a common bacterium which is found in food and is one of the leading causes of food poisoning in people (Warrell). People become sick from the ingestion of the bacteria which then germinates in the body. It is extremely common, infecting as many as a million people each year (Clostridium). The bacteria can be found in meat and particularly in poultry that is not cooked properly. Also, if these products are left out too long and not refrigerated, then they can develop C. perfringens bacteria. The bacteria can live in foods despite proper heating, which makes it dangerous to eat food matter that has been left out too long and not properly stored. Most instances of C. perfringens infection are traced back to large institutional settings, such as restaurants or school cafeterias where large amounts of food are prepared and allowed to set for too long a period of time (Clostridium). It is believed that because so much food goes out in these settings, those preparing the food may become careless in their work. The cooking process kills the adult bacteria, but the spores of the bacteria survive and can germinated in the food after it has cooled down, which is prevented if the food is properly stored. The bacteria thrive at room temperatures, but are arrested at very high or very low temperatures. C. perfringens bacteria can only be passed through consumption of food matter and cannot be passed from one person to another through indirect interactions (CDC). It was originally believed to be contagious because people within a single household might all be affected, but science has shown that this is because the members of the household will be likely to eat the same food.

Symptoms of Infection:

People who are infected with C. perfringens will likely show symptoms, although some people become infected without showing any symptoms and the bacteria passes through their system without incident. Usually, the patient will show signs of infection at some point between six and 24 hours after the ingestion of the material containing the bacteria. Most people afflicted will experience mile to severe cramping of the patient's abdominal muscles, watery or prolonged diarrhea, some vomiting, and in some cases a patient may experience fever as well (Warrell). Vomiting and fever are two of the rarer symptoms and usually indicates a complication or a concurrent medical condition. Patients will most often suffer from the food poisoning for a period of 24-48 hours before it passes through their digestive system. The Center for Disease Control and Prevention has stated that C. perfringens is most dangerous for very young people or the elderly. These two groups will usually experience worse symptoms for a longer period of time than normal, healthy adults dealing with the bacteria (CDC). Some people who have extreme cases of infection may show symptoms for a full week to two weeks. Unfortunately, some people have died from C. perfringens food poisoning due to a rare strain of the bacteria known as type C which has most often been found in developing or undeveloped countries. According to an article in Britain's The Daily Mail, "It is not usually fatal and only one in 10,000 victims die -- mainly the elderly, babies or those with an underlying illness" (Borland). C. perfringens can also be fatal in cases of gas gangrene wherein the bacterium putrefies the tissues and creates bacterial toxins in the body. When this happens, a massive edema and inflammation is the result, which is often fatal.

Testing for the Bacteria:

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