The dangerous E coli bacteria

Heather Little-White, PhD, Contributor

It takes the deadly scare of E. coli contamination to make people sceptical about food, its source and methods of preparation. Investigations into the source of the recent E. coli outbreak in Europe, have led to bean sprouts from an organic farm in northern Germany. According to reports, the outbreak has killed over 30 people and infected thousands more.

Bean sprouts are the crisp, tender sprouts of various germinated beans and seeds. Mung bean sprouts are popular in Chinese cooking where they are sautéed or stir-fried. Other sprouts used in cooking include alfalfa, soybeans and lentils.

Types of E. coli

E. Coli (Escherichia coli) is a bacterium that thrives in the intestinal tract of humans and animals. There are many types of E. coli and most of them are harmless. Some strains may cause bloody diarrhoea (enterohemorrhagic E. coli) while other strains can cause urinary-tract or other infections.

One common strain is the E. coli O157:H7, which may cause severe anaemia or kidney failure, and may also lead to death. This strain may come from eating raw or undercooked ground beef, or unpasteurised milk. The health-related problems from consuming food contaminated by E. coli include vomiting, abdominal cramps, bloody diarrhoea, nausea and this may even cause complications leading to death.

Food contamination

Other likely sources of E. coli contamination of food include:

During processing, meat should be cooked to temperatures above 160F. to kill harmful bacteria. To ensure that there is no contamination by strains of E. coli, meat should be reheated thoroughly and ground beef used in hamburgers should be cooked properly.

Raw milk or dairy products where the E. coli bacteria can spread from a cow's udders to its milk. Dairy products should have the word 'pasteurised', indicating that the food has been heated to destroy bacteria.

Raw fruits and vegetables, such as lettuce, alfalfa sprouts, or unpasteurised apple cider or other unpasteurised juices, that may have come in contact with infected animal faeces.

Person-to-person contact

E. coli bacteria can be passed from person to person if an infected person does not wash their hands after defecating, so the bacteria can spread to other people or objects. Hands should be washed front and back as often as possible, as bacteria multiply on warm, moist hands easily picked up from surfaces, food and other individuals.

Water contamination

Critical to food preparation is the safe supply of water. Water may be contaminated with human or animal faeces and common sources are lakes, pools, irrigation canals and the public water supply. The public water supply should be treated with chlorine. Travellers' diarrhoea may be caused by drinking infected water.

Cross-contamination

Avoid cross-contamination of food by transferring bacteria from one food to another by dirty utensils, cutting boards, plates and hands.

Cutting surfaces should be kept clean and there should be cutting boards for different functions, for example, vegetables should not be cut on the same surface as meat, and meat should be cut on a different board from the one used for fish or poultry. Colour-coded cutting boards are becoming increasingly popular, because they reduce the risk of cross-contamination. Cutting boards should air-dry naturally.

Sanitising solutions should be used at the dish-washing chain - scraping, washing and rinsing. Two teaspoons of chlorine bleach in a quart of water is safe.

Dish towels should be changed and washed every day and allowed to sun-dry.

Safe food preparation is important in keeping the family safe, especially younger and older family members who are at greater risk for food-borne illness, as the immune system has less ability to fight back.

Heather Little-White, PhD, is a nutrition and lifestyle consultant in Kingston. Send comments to editor@gleanerjm.com or fax: 922-6223.