Dr. Alok Agarwal
Foodborne illness, sometimes called "foodborne disease," "foodborne infection," or "food poisoning, is a common, costly—yet preventable—public health problem. Many different disease-causing microbes, or pathogens, can contaminate foods, so there are many different foodborne infections.
In addition, poisonous chemicals, or other harmful substances can cause foodborne diseases if they are present in food.
- More than 250 different foodborne diseases have been described. Most of these diseases are infections, caused by a variety of bacteria, viruses, and parasites that can be foodborne.
- Other diseases are poisonings, caused by harmful toxins or chemicals that have contaminated the food, for example, poisonous mushrooms.
- These different diseases have many different symptoms, so there is no one "syndrome" that is foodborne illness. However, the microbe or toxin enters the body through the gastrointestinal tract, and often causes the first symptoms there, so nausea, vomiting, abdominal cramps and diarrhoea are common symptoms in many foodborne diseases.
The types of Foodborne diseases are: Botulism; Campylobacteriosis; E. coli; Hepatitis A; Norovirus Infection; Salmonellosis and Shigellosis.
Symptoms of Foodborne Illness:
- Common symptoms of foodborne illness are diarrhea and/or vomiting, typically lasting 1 to 7 days. Other symptoms might include abdominal cramps, nausea, fever, joint/back aches, and fatigue.
- What some people call the “stomach flu” may actually be a foodborne illness caused by a pathogen (i.e., virus, bacteria, or parasite) in contaminated food or drink.
- The incubation period (the time between exposure to the pathogen and onset of symptoms) can range from several hours to 1 week.
Foods associated with Foodborne Illness:
- Raw foods of animal origin, that is, raw meat and poultry, raw eggs, unpasteurized milk, and raw shellfish are the most likely to be contaminated.
- Fruits and vegetables can also be contaminated with animal waste when manure is used to fertilize produce in the field, or unclean water is used for washing the produce.
- Raw sprouts are particularly concerning because the conditions under which they are sprouted are ideal for growing microbes.
- Unpasteurized fruit juices or cider can also be contaminated if there are pathogens on the fruit that is used to make it.
- Any food item that is touched by a person who is ill with vomiting or diarrhoea, or who has recently had such an illness, can become contaminated. When these food items are not subsequently cooked (e.g., salads, cut fruit) they can pass the illness to other people.
Causes of foodborne illness
The causes of foodborne illness fall into the following three categories:
- Biological hazards include bacteria, viruses, and parasites. Bacteria and viruses are responsible for most foodborne illnesses. Biological hazards are the biggest threat to food safety. This can be inherent in the product or due to mishandling (e.g. time/temperature abuse).
- Chemical hazards include natural toxins and chemical contaminants. Some natural toxins are associated with the food itself (that is certain mushrooms, PSP in molluscan shellfish), some are made by pathogens in the food when it is time/temperature abused (that is histamine development in certain seafood species). Some additives, such as sulfites, can be a hazard to certain individuals. Chemical contamination can also occur when products, such as cleaners and sanitizers are not used correctly.
Food allergens are also a chemical hazard. Some people are sensitive to proteins in foods. Every food is different. Regulatory authorities have identified 8 food allergens that cause 90% of the allergic reactions. These are milk, eggs, fish, crustacean shellfish (lobster, crab, shrimp), wheat, soy, peanuts, and tree nuts.
Physical hazards can include metal shavings from cans, wires from a grill bristle, and plastic pieces or broken glass.
Prevention of foodborne illness
Follow these four simple steps to keep food safe:
- Clean: Wash hands and food contact surfaces and utensils often, between tasks, and if they have become contaminated. Effective cleaning involves removing soil and debris, scrubbing with hot soapy water and rinsing, using potable/drinking water. Sanitizing involves the use of high heat (e.g. a dishwasher) or chemicals (e.g. chlorine bleach) to reduce or eliminate the number of microorganisms or germs to a safe level.
Wash hands with warm water and soap for 20 seconds and dry with a disposable paper towel or clean hand cloth.
- Wash cutting boards, dishes, and utensils after preparing each food item and before you use it for the next food.
- Use hot, soapy water, rinse with hot water, and air dry or dry with a clean paper towel or clean dish cloth.
- Wash countertops after preparing each food item and before you use it for the next food.
- Wash dish cloths often in the washing machine.
- Store sponge in a place so it can dry after use.
- Replace the dish sponge often.
- Separate to prevent cross contamination. Cross contamination is the transfer of harmful bacteria from uncooked food products (e.g. raw meat, fish, and poultry) or unclean people, countertops, and kitchen equipment to ready-to-eat foods (e.g., fruits, vegetables, deli meats/cheeses, and prepared or cooked foods).
- Prevent cross contamination when grocery shopping.
- Prevent cross contamination when storing food in the refrigerator.
- Prevent cross contamination when handling, preparing, and serving food.
- Cook food thoroughly and use a thermometer to verify the proper temperature was reached.
- Cook foods to the safe minimum internal cooking temperature, as indicated in the table below.
- To determine that the proper temperature was reached, place a food thermometer in the thickest part of the food and allow the thermometer to equilibrate.
- Clean your food thermometer with hot, soapy water before and after each use!
- For information on safe cooking temperatures for different foods,
- Chill foods promptly. Cold temperatures slow the growth of harmful bacteria. Cold air must circulate to help keep food safe, so do not over fill the refrigerator. Maintain the refrigerator temperature at 41°F or below. Place an appliance thermometer in the rear portion of the refrigerator, and monitor regularly. Maintain the freezer temperature at 0°F or below.
- Refrigerate and/or freeze meat, poultry, eggs and other perishables as soon as possible after purchasing.
- Consider using a cooler with ice or gel packs to transport perishable food.
- Perishable foods, such as cut fresh fruits or vegetables and cooked food should not sit at room temperature more than two hours before putting them in the refrigerator or freezer (one hour when the temperature is above 90°F).
- There are three safe ways to thaw food: in the refrigerator (see Separate), in cold water, and in the microwave. Food thawed in cold water or in the microwave should be cooked immediately.
- Cool leftovers quickly by dividing large amounts into shallow containers for quicker cooling in the refrigerator.