Food Poisoning Health Article

Definition

Food poisoning is a general term for health problems arising from eating contaminated food. Food may be contaminated by bacteria, viruses, environmental toxins, or toxins present within the food itself, such as the poisons in some mushrooms. Symptoms of food poisoning usually involve the prompt onset of vomiting and diarrhea. Some toxins also affect the nervous system.

Description

Every year millions of people suffer from bouts of vomiting and diarrhea that they blame on "something I ate." These people are generally correct. The Centers for Disease Control and Prevention (CDC) estimates that there are from six to 33 million cases of food poisoning in the United States each year. Many cases are mild and pass so rapidly that they are never diagnosed. Occasionally a severe outbreak creates a newsworthy public health hazard.

Classical food poisoning, sometimes incorrectly called ptomaine poisoning, is caused by a variety of different bacteria. The most common are Salmonella, Staphylococcus aureus, Escherichia coli O157:H7, Shigella, and Clostridium botulinum. Each has a slightly different incubation period and duration, but all except C. botulinum cause inflammation of the intestines and diarrhea. Sometimes food poisoning is called bacterial gastroenteritis or infectious diarrhea. Food and water can also be contaminated by viruses (cholera, rotavirus), environmental toxins (heavy metals), and poisons produced within the food itself (mushroom poisoning or fish and shellfish poisoning).

Careless food handling creates conditions for the growth of bacteria that make people sick. Food can become contaminated at many different points during its trip from farm to table. Vegetables that are eaten raw, such as lettuce, may be contaminated by bacteria in soil, water, and dust during washing and packing. Home canned and commercially canned food may be improperly processed at too low a temperature or for too short a time to kill the bacteria.

Raw meats carry many foodborne bacterial diseases. The United States Food and Drug Administration (FDA) estimates that 90% or more of raw poultry sold at retail carries some disease-causing bacteria. Other raw meat products and eggs are contaminated to a lesser degree. Thorough cooking kills the bacteria and makes the food harmless. However, properly cooked food can become recontaminated if it comes in contact with plates, cutting boards, counter tops, or utensils that were used with raw meat and not cleaned and sanitized.

Cooked foods can also be contaminated after cooking by bacteria carried by food handlers or from bacteria in the environment. It is estimated that 50% of healthy people have the bacterium Staphylococcus aureus in their nasal passages and throat, as well as on their skin and hair. Rubbing a runny nose, then touching food can introduce the bacteria into cooked food. Bacteria flourish at room temperature and will rapidly grow into quantities capable of making people sick. To prevent this growth, food must be kept hot or cold, but never just warm.

Although the food supply in the United States is probably the safest in the world, anyone can get food poisoning. Serious outbreaks are rare. When they occur, the very young, the very old, and those with immune system weaknesses have the most severe and life-threatening cases. For example, this group is 20 times more likely to become infected with the Salmonella bacterium than the general population.

Travel outside the United States to countries where less attention is paid to sanitation, water purification, and good food handling practices increases the chances that a person will get food poisoning. People living in institutions such as nursing homes are also more likely to get food poisoning.

Rotavirus is the most common cause of severe diarrhea in children and accounts for the hospitalization of an estimated 55,000 children in the United States and over 600,000 deaths of children worldwide per year.

Other less common but serious food-borne illnesses may arise from consuming animals infected with Bovine spongiform encephalopathy. Bovine spongiform encephalopathy (BSE) is a degenerative disorder affecting the central nervous system in cattle. It is also commonly referred to as "mad cow disease." BSE results from an "unconventional transmissible agent" which is yet to be determined precisely but is thought to be a pathogenic protein. Cell death leads to holes in the brain, creating a "sponge-like" consistency, which results in the animal's death. As of November 2000, there have been more than 177,500 cases of BSE confirmed in the United Kingdom (UK). However, no cases have been reported in the United States, where the food supply has been monitored closely. Imports of ruminants (suborder of mammals that includes sheep) and ruminant products have been restricted to some degree from countries where BSE was reported and has extended to all European countries. BSE is believed to be linked to a new variation of Creutzfeldt-Jakob disease (CJD) in humans, which is a progressive neurological disorder that can lead to death.