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Learn the causes of E. coli infections and steps you can take to avoid getting sick.

You've probably heard of E. coli—a group of bacteria that can cause severe cramps and diarrhea. E. coli makes the headlines all too often when people get sick from eating contaminated food products. Fortunately, there's a lot you can do to help protect yourself and your family.

Here are some answers to questions about this common foodborne illness.

Q: What is E. coli?

A: E. coli—short for Escherichia coli—is a large and diverse group of bacteria. While most strains of E. coli are harmless, others can make you very ill. Outbreaks of foodborne disease caused by E. coli have become a particularly serious problem.

E. coli infections are most common during the summer months.

Q: What causes E. coli?

A: According to the Centers for Disease Control and Prevention (CDC), you can get E. coli by eating contaminated food or through contact with the stool of an infected person or animal. You can also get an E. coli infection by drinking contaminated water or unpasteurized milk, apple juice or cider or eating contaminated, uncooked fruits or vegetables.

One of the most common causes of E. coli is eating undercooked ground beef. Healthy beef and dairy cattle may carry the E. coli germ in their intestines. During the slaughtering process, meat can become contaminated with the bacteria. When the beef is ground up, the E. coli germs get mixed throughout the meat. If you don't cook the ground beef at a high enough temperature or long enough, you can be infected with E. coli when the germs go into your stomach and intestines.

According to the U.S. Department of Agriculture, ground beef should be cooked to an internal temperature of at least 160 degrees.

Q: What are the symptoms of E. coli?

A: The symptoms of E. coli usually show up 3 or 4 days after exposure, but may occur between 1 and 10 days after exposure. The symptoms often include severe abdominal cramps, diarrhea that is often bloody, vomiting, and a mild fever.

Symptoms of E. coli are generally most severe in children, older people and anyone who already has another illness, according to the American Academy of Family Physicians (AAFP).

If you have any symptoms of E. coli, it's important to see a doctor right away.

Q: Can E. coli cause serious complications?

A: Some people develop a potentially life-threatening complication of E. coli infection called hemolytic uremic syndrome (HUS). This is most common in very young children and the elderly.

Symptoms of HUS can include bloody diarrhea, pale skin, and feeling irritable or lethargic.

It is important to contact a doctor right away if you think you or a loved one may have HUS because it can damage kidneys or even lead to kidney failure, according to the AAFP.

Q: How is E. coli diagnosed?

A: To diagnose E. coli, your doctor must examine a stool culture to find out if you have the bacteria in your intestines. The culture must be taken within 48 hours after the bloody diarrhea starts, according to the AAFP.

Q: How is the infection treated?

A: There's no specific treatment for E. coli. However, it's important to drink a lot of water to help prevent dehydration, according to the AAFP. You should not take medicine for diarrhea unless it is approved by your doctor. Some medicines can stop your intestines from getting rid of the E. coli bacteria. If you are seriously dehydrated, you may need to go to the hospital and receive fluids intravenously.

Q: How can I avoid E. coli?

A: There are several steps you can take to keep from getting an E. coli infection. Most important, you should always follow food safety rules when handling or cooking meat. Learn more about preventing foodborne illness in the Food Safety health topic center.

You should also wash your hands with soap and water for at least 30 seconds before cooking and after using the bathroom, according to the AAFP.

To learn more about E. coli and how to avoid getting infected, talk to your doctor or visit the CDC website at cdc.gov.

Reviewed 5/21/2024