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Ohio State University Extension Fact Sheet

Family and Consumer Sciences

1787 Neil Avenue, Columbus, Ohio 43210-1295



A Constant Challenge


Barbara Rohrs

Have you ever had "food poisoning?" Food poisoning is the common term many people use to refer to foodborne illness. When a source for an outbreak is identified, salmonella is one of the most common types of foodborne illnesses reported. It is responsible for millions of cases of foodborne illnesses each year.

What are the symptoms?

The exact number of salmonella foodborne illnesses each year is hard to determine because many people attribute their illness to a virus or flu. The symptoms are very similar and include abdominal pain, headache, nausea, vomiting, fever, and diarrhea. Since the incubation period for salmonellosis is 8 to 72 hours it is often hard to trace back to the food that was eaten. Influenza often lasts longer than the two to three days of salmonella foodborne illness.

Where does salmonella come from?

Foods usually involved in salmonellosis are poultry and poultry salads, meat and meat products, raw milk, shell eggs, egg custards, improperly cooked mayonnaise, ice cream, sauces, and other protein foods. Once people believed that cracked shells were the only source of salmonella in eggs. However, salmonella was found in healthy hens and uncracked eggs. Futher investigation showed hens that have eaten mouse feces can produce infected eggs. Now we know that salmonella is in domestic and wild animals and even in the intestinal tract of people. It is important to keep pets out of the kitchen when preparing food for this reason.

Is food the only source?

Iguanas and lizards are growing in popularity as pets. They are also carriers of salmonella. Children under the age of five should not have direct contact with iguanas and other reptiles. Young children have an increased risk for reptile-associated salmonellosis and complications such as meningitis.

How can I reduce my risk?

The salmonella pathogen that causes this foodborne illness is very hard to get rid of, but it can be controlled by careful food preparation. Take these precautions when handling meat, milk, poultry and both raw eggs and foods containing eggs.

1.Avoid eating raw eggs and foods containing raw eggs: homemade Caesar salad, homemade Hollandaise sauce, and homemade mayonnaise, for example. Also homemade ice cream and homemade eggnog should be avoided unless made with a cooked, custard-type base. Commercial forms of these products are safe to serve since they are made with pasteurized liquid eggs. Commercial pasteurization destroys salmonella bacteria. Review traditional recipes that have raw or undercooked eggs and replace them with recipes that thoroughly cook eggs.

2.Cook eggs thoroughly until both the yolk and the whites are firm. This is especially important for people most at risk for foodborne illness. Fried eggs should be cooked on both sides or in a covered pan. Scrambled eggs should be cooked until firm throughout.

3.Realize that eating lightly-cooked foods containing eggs, such as meringues, and French toast, may be risky for people in high-risk groups.

4.Wash hands, utensils, equipment, and work areas with hot soapy water before and after they come in contact with eggs, egg-containing foods, raw meat and poultry


  1. National Center for Disease Control, Center for Disease Control and Prevention

  2. U.S. F DA, Center for Food Safety and Applied Nutrition, Foodborne Pathogenic Microorganisms and Natural Toxins Handbook, The Bad Bug Book.
  3. U.S. FDA, Center For Food Safety & Applied Nutrition, MMWR43 (40): 1994 Oct. 14
  4. Texas Agricultural Extension Service Newsletter, July-September 1995.
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