The Food Spoilers: Bacteria and Viruses

A foodborne illness may be caused by a variety of things associated with foods. Bacteria, viruses, parasites, natural plant toxins, and commercial chemicals can all cause foodborne illnesses. This publication deals with foodborne illnesses caused by the microorganisms we think of as germs—bacteria and viruses.

If you contract a foodborne illness you may think you have the flu or a virus that is going around. This is natural because the symptoms of food poisoning are similar to those of other illnesses. These symptoms often include diarrhea, vomiting, abdominal cramps, fever, chills, and headache.

In contagious diseases, you contract the disease from another human. With foodborne illnesses, the germs are on food or in water. Humans or animals may transfer the germs to the food or water, but you actually contract the illness from what you eat or drink.

Bacteria and viruses are located almost everywhere—in the soil, water, and air. Therefore, it is very difficult to rid a food product of all germs. The necessary conditions for germs to grow include:

• Nourishment—foods are an excellent source.
• Correct temperature—between 40 and 140 degrees Fahrenheit. When foods are not in the refrigerator or being cooked, they will usually be in this range.
• Time to grow.

As the following table shows, very little time is needed for germs to grow. It takes only about 20 minutes for them to double their number if the conditions are right. A single bacterium can reproduce to over 60 in 2 hours, to over 500 in 3 hours, to over 2 million in 7 hours. When you consider that many bacteria may be present in the beginning, you can see how important it is to take precautions, including good personal hygiene and proper food handling.

This publication can help you avoid foodborne illnesses by providing you with:

• Descriptions of the major microorganisms as they relate to foodborne illnesses.
• Habitat—where the germs are found.
• Foods involved—water and foods that are a good place for the germs to live.

Bacterial Growth Rate
	Time		Bacteria
	8:00		1
	8:20		2
	8:40		4
	9:00		8
	9:20		16
	9:40		32
	10:00		64
	10:20		128
	10:40		256
	11:00		512
	11:20		1,024
	11:40		2,048
	12:00		4,096
	12:20		8,192
	12:40		16,384
	1:00		32,768
	1:20		65,536
	1:40		131,072
	2:00		262,144
	2:20		524,288
	2:40		1,048,576
	3:00		2,097,152

• Method of transmission&3151;how you can get the illness.
• Symptoms—:signs of sickness.
• Onset—how long it takes for you to get sick.
• Duration—how long the illness may last.
• Prevention—what you can do to keep from getting sick.

The number of germs required to cause illness varies between types of germs and between individuals. Those people most vulnerable to foodborne illnesses include the elderly, infants, and people who are already sick. The people in these groups have one thing in common: their immune systems are not as capable of fighting off germs.

For more detailed information about a certain foodborne illness, contact your county Extension agent or local health department.

Bacteria In Foods

How to Fight the Food Spoilers

• When shopping for food, pick up perishable foods, meat, poultry, and dairy items last; get them home and into the refrigerator or freezer quickly.

• Never buy food in damaged containers such as leaking, bulging, or severely dented cans, cracked jars, or jars with loose or bulging lids.

• Maintain a refrigerator temperature of 40 degrees F (2 to 4 degrees C) or below, and a freezer temperature of 32 degrees F (0 degrees C) or lower. Check each frequently.

• Thaw meat and poultry in the refrigerator or, for faster results, in a watertight package under cold running water.

• Wash hands thoroughly with soap and warm water before handling foods.

• After handling raw foods such as meat, poultry, vegetables, or fruits, wash your hands before touching other foods or food surfaces.

• Wash utensils, containers, and work surfaces before and after they come into contact with raw foods, especially meat or poultry.

• Always keep hot foods hot (above 140 degrees F) and cold foods cold (below 40 degrees F).

• Refrigerate leftovers promptly in properly covered containers.

1. Preserve the evidence. Wrap remaining food securely, mark “DANGER,” and freeze it. Save all the packaging material. Write down all available information about the food and symptoms. Save any identical unopened products.

2. Seek treatment as necessary. If the victim is in an at-risk group or if symptoms persist or are severe (bloody diarrhea, excessive nausea and vomiting, high temperature), call your doctor.

3. Call the local health department if the suspect food was served at a large gathering, from a restaurant, or if it is a commercial product.

   

4. Call the USDA Meat and Poultry Hotline (1-800-535-4555) if the suspect food is a USDA-inspected product and you have all the packaging.

HE-0654 Revised March 2004. Jean Weese, Extension Food Scientist, Associate Professor, Nutrition and Food Science; William R. Jones, former Extension Animal Scientist, Professor, Animal Sciences, Auburn University. Originally prepared by Benjy Mikel, former Extension Food Scientist.

For more information, contact your county Extension office. Visit http://www.aces.edu/counties or look in your telephone directory under your county's name to find contact information. Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, and other related acts, in cooperation with the U.S. Department of Agriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color, national origin, religion, sex, age, veteran status, or disability.