E. coli is a type of bacteria that normally lives in the intestines, where it helps the body break down and digest the food we eat. But certain types (or strains) of E. coli are infectious and spread through contaminated food or water, or from other infected people or animals.
Infections due to E. coli (Escherichia coli) bacteria can cause severe, bloody diarrhea. Some cases can lead to serious health problems. Fortunately, most healthy people who get an infection don't develop serious problems and recover on their own without treatment.
How Do E. Coli Infections Happen?
Most often, E. coli spreads when someone eats food that contains the bacteria. At-risk foods include:
undercooked ground beef (such as in hamburgers)
produce grown in animal manure (of cows, sheep, goat, or deer) or washed in contaminated water
unpasteurized dairy or juice products
The bacteria also can spread from person to person on unwashed hands and surfaces, by swimming in contaminated water, and from touching animals at farms or petting zoos.
What Are the Signs of an E. Coli Infection?
Some types of E. coli bacteria make a toxin (a poisonous substance) that can damage the lining of the small intestine. This can lead to bad stomach cramps, vomiting, and diarrhea (often with blood in it). When that happens, people can get dehydrated.
Symptoms usually start 3–4 days after a person has come into contact with the bacteria and end within about a week.
Are E. Coli Infections Contagious?
An E. coli infection is contagious for at least as long as the person has diarrhea, and sometimes longer.
What Problems Can Happen?
Most people recover completely from an E. coli infection. But some can develop a serious kidney and blood problem called hemolytic uremic syndrome (HUS).
Signs of HUS include:
decreased urination (peeing)
a pale or swollen appearance
bleeding from the nose or gums
HUS can be life-threatening and needs to be treated in a hospital.
A doctor might take a stool sample to look for E. coli bacteria. Blood tests may be used to check for possible complications.
Antibiotics aren't helpful and, in fact, can be harmful. Likewise, anti-diarrheal medicines can increase the risk of complications and should not be used.
Kids with an E. coli infection should rest as much as possible and drink plenty of fluids to avoid dehydration. Those who become dehydrated might need to be hospitalized to get IV fluids, and those with HUS may need dialysis for kidney failure and/or blood transfusions.
While recovering from an infection, kids can return to their normal activities after two stool cultures are free of the bacteria. Don't let kids use swimming pools or water slides until 2 weeks after all symptoms have gone away.
Can E. Coli Infections Be Prevented?
E. coli outbreaks have been tied to a wide variety of foods, such as fresh spinach, hamburgers, ground beef, bologna, hazelnuts, packaged cheeses, shredded lettuce, and prepackaged cookie dough.
Teach your kids the importance of regular, thorough hand washing, especially after going to the bathroom, touching animals, or playing outside, and before eating or preparing food. They should avoid swallowing water while swimming.
When Should I Call the Doctor?
Call your doctor if your child has any symptoms of an E. coli infection, especially stomach pain or lasting, severe, or bloody diarrhea.
Call immediately if your child shows signs of dehydration, such as peeing less than normal, or of hemolytic uremic syndrome, especially if your child had a recent gastrointestinal illness.