by Jones P

image for food allergy article Salmonella and E. coli have become well known causes of foodborne illness in the United States. The Centers for Disease Control and Prevention (CDC) work to find and contain the source of the illnesses.

Finding the source can be hard. Food is tracked from its farm through processing, packaging, store, and to homes or restaurants. Salmonella and E. coli are common causes, but there are many other bacteria, parasites, or viruses that cause illness. They can be picked up at any point along the food supply route. Poisonous chemicals or agents can also get into foods and cause illness. It can make a person wonder if any food can be trusted.

Why Worry?

Food-related illnesses often only cause minor sickness. Most people get better in a couple of days. The illness may cause diarrhea, vomiting, and cramping. However, for some, food poisoning can lead to disability or death. Pregnant women are at higher risk. It can lead to miscarriage, premature birth, or stillbirth. People with immune system problems also have a higher risk of more serious illness.

There are steps a person can take to lower the risk of these illnesses. Pasteurization and safety standards in food preparation and canning are just a few examples. Other processes like food irradiation are newer methods. It is not possible to wipe out every germ in the food process route. People also need to be aware of their role in lowering risk.

Food Watch

Agencies, such as the CDC, are always working to find and contain sources of foodborne illnesses. Meanwhile bacteria, viruses, and parasites are changing and finding new ways to grow. New illnesses may arise from new areas or with new packaging and processing methods. Different countries also have different food care standards and enforcements. Imported foods from other countries have caused some food illness outbreaks.

Public health departments track cases of foodborne illness. Many people with the same symptoms suggest a larger problem. Tests of virus or bacteria can confirm that one problem is causing widespread illness. Public health staff can track where people ate or bought food. It can help to find restaurants, grocery stores, or farms that may be the start of the illness. Foods may be recalled or restaurants may be closed to prevent more people from getting sick. Problems may be found at:

  • Farm or food source. Contaminated fertilizers or water can pass germs to food that grows in the soil. Sick animals can also pass some germs to humans. Seafood can become contaminated by bacteria in the water and pollution. Animals in cramped spaces can easily spread harmful germs.
  • Food processing plants. Water used to process foods may be contaminated. Water can also wash germs from one item and spread it to others if the same water is used. Human contact can also pass germs to food.
  • Slaughter centers. One sick animal can contaminate large batches of ground meat.
  • Kitchen. A food handler can pass germs during preparation. Washing hands is the best way to avoid this. Food also needs to be properly washed and stored. Surfaces and kitchen tools also need to be properly cleaned and stored. Germs can be spread through a whole meal in a dirty kitchen. Certain foods will also need to be cooked at a certain temperature to lower the risk of infections.
  • Home. Storing foods in the fridge can slow or stop the growth of germs.

How to Stay Safe

A person may not have much control over the first part of a food's journey. Read labels. Make sure the grocery store is clean and the food is well stored. Avoid foods stored in refrigerators that do not seem to be working well. Look for expiration or used by dates and follow them. Check the health department rating of restaurants. When dining out, ask that food be cooked thoroughly.

Steps to take at home:

  • Hands should be washed before making a meal and after contact with raw food.
  • Cook food thoroughly:
    • Eggs should be cooked until the yolk is firm.
    • Use a thermometer to make sure meat and poultry are cooked well.
    • Look on packages or kitchen thermometers for temperature goals.
  • Keep leftovers in the fridge. Do not let them sit out for too long.
  • Keep the refrigerator set at 40 ºF (degrees Fahrenheit)/4 ºC (degrees Celsius) or below.
  • Wash fruits and veggies before eating.
  • Keep raw foods separate while making the meal.
  • Wash kitchen tools and surfaces before moving to different type of food.
  • Use pasteurized eggs and dairy.

Food for Thought

Some foods have a higher risk of causing illness than others. Consider risks before eating:

  • Sushi and other raw fish, especially shellfish
  • Unpasteurized milks and juices
  • Ready to eat meats—hot dogs or luncheon meats
  • Soft cheeses, unless they are labeled as made from pasteurized milk
  • Refrigerated pates or meat spreads
  • Refrigerated smoked seafood (safe if it is cooked)
  • Raw eggs
  • Unwashed fruits and veggies

These foods should not be eaten by people at a higher risk of severe infections. This can include those with long-term illnesses, weak immune systems, and women who are pregnant.


Fight BAC!—Partnership for Food Safety Education 

National Restaurant Association 


Canadian Food Inspection Agency 

Health Canada 


Definition & facts of food poisoning. National Digestive Diseases Information Clearinghouse website. Accessed August 25, 2020.

Foodborne illnesses. EBSCO DynaMed website. Available at: . Accessed August 25, 2020.

Foodborne illness and disease. United States Department of Agriculture website. Available at: Accessed August 25, 2020.

Shane AL, Mody RK, et al. 2017 Infectious Diseases Society of America Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea. Clin Infect Dis. 2017 Nov 29;65(12):e45-e80.

Steps in a foodborne outbreak investigation. Centers for Disease Control and Prevention website. Available: Accessed August 25, 2020.

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