Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get Started
About our e-newsletters
- Free e-newsletters
- Mayo Clinic expertise
- We do not share your e-mail address
Housecall, our weekly general-interest e-newsletter, keeps you up to date on a wide variety of health topics with timely, reliable, practical information, recipes, blogs, questions and answers with Mayo Clinic experts and more. Our biweekly topic-specific e-newsletters also include blogs, questions and answers with Mayo Clinic experts, and other useful information that will help you manage your health.
Housecall Archives
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Causes
By Mayo Clinic staffContamination of food can happen at any point during its production: growing, harvesting, processing, storing, shipping or preparing. Cross-contamination — the transfer of harmful organisms from one surface to another — is often the cause. This is especially troublesome for raw, ready-to-eat foods, such as salads or other produce. Because these foods aren't cooked, harmful organisms aren't destroyed before eating and can cause food poisoning.
Many bacterial, viral or parasitic agents cause food poisoning. The following table shows some of the possible contaminants, when you might start to feel symptoms and common ways the organism is spread.
| Contaminant | Onset of symptoms | Foods affected and means of transmission |
|---|---|---|
| Campylobacter | 2 to 5 days | Meat and poultry. Contamination occurs during processing if animal feces contact meat surfaces. Other sources include unpasteurized milk and contaminated water. |
| Clostridium perfringens | 8 to 16 hours | Meats, stews and gravies. Commonly spread when serving dishes don't keep food hot enough or food is chilled too slowly. |
| Escherichia coli (E. coli) O157:H7 | 1 to 8 days | Beef contaminated during slaughter. Spread mainly by undercooked ground beef. Other sources include unpasteurized milk and apple cider, alfalfa sprouts, and contaminated water. |
| Giardia lamblia | 1 to 2 weeks | Raw, ready-to-eat produce and contaminated water. Can be spread by an infected food handler. |
| Hepatitis A | 28 days | Raw, ready-to-eat produce and shellfish from contaminated water. Can be spread by an infected food handler. |
| Listeria | 9 to 48 hours | Hot dogs, luncheon meats, unpasteurized milk and cheeses, and unwashed raw produce. Can be spread through contaminated soil and water. |
| Noroviruses (Norwalk-like viruses) | 12 to 48 hours | Raw, ready-to-eat produce and shellfish from contaminated water. Can be spread by an infected food handler. |
| Rotavirus | 1 to 3 days | Raw, ready-to-eat produce. Can be spread by an infected food handler. |
| Salmonella | 1 to 3 days | Raw or contaminated meat, poultry, milk or egg yolks. Survives inadequate cooking. Can be spread by knives, cutting surfaces or an infected food handler. |
| Shigella | 24 to 48 hours | Raw, ready-to-eat produce. Can be spread by an infected food handler. |
| Staphylococcus aureus | 1 to 6 hours | Meats and prepared salads, cream sauces and cream-filled pastries. Can be spread by hand contact, coughing and sneezing. |
| Vibrio vulnificus | 1 to 7 days | Raw oysters and raw or undercooked mussels, clams and whole scallops. Can be spread through contaminated seawater. |
- Diagnosis and management of foodborne illnesses: A primer for physicians and other health care professionals. Rockville, Md.: Agency for Healthcare Research and Quality. http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=5266&nbr=3593. Accessed April 20, 2009.
- Bacteria and foodborne illness. National Digestive Diseases Information Clearinghouse (NDDIC). http://www.digestive.niddk.nih.gov/ddiseases/pubs/bacteria/index.htm. Accessed April 20, 2009.
- Foodborne illness. Centers for Disease Control and Prevention. http://www.cdc.gov/ncidod/dbmd/diseaseinfo/foodborneinfections_g.htm. Accessed April 20, 2009.
- Basics for handling food safely. United States Department of Agriculture Food Safety and Inspection Service. http://www.fsis.usda.gov/PDF/Basics_for_Safe_Food_Handling.pdf. Accessed April 20, 2009.
- Centers for Disease Control and Prevention, et al. Diagnosis and management of foodborne illnesses: A primer for physicians and other health care professionals. MMWR Recommendations and Reports. 2004;53:1. http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5304a1.htm. Accessed April 20, 2009.
- Avoid foodborne illness: Fight BAC! American Medical Association. http://www.ama-assn.org/ama/upload/mm/36/foodborne_patient.pdf. Accessed April 20, 2009.
- Listeriosis. Centers for Disease Control and Prevention Division of Foodborne, Bacterial and Mycotic Diseases. http://www.cdc.gov/nczved/dfbmd/disease_listing/listeriosis_gi.html. Accessed April 20, 2009.
- Conlon CP. Food-borne and water-borne infections. In: Cohen J, et al. Infectious Diseases. 2nd ed. New York, N.Y.: Mosby; 2004. http://www.mdconsult.com/das/book/body/132803244-4/0/1209/288.html?tocnode=49354199&fromURL=288.html#4-u1.0-B0-323-02407-6..50095-7_3004. Accessed April 21, 2009.
