Is e coli contagious?


Is E. coli Contagious? How to Minimize Your Risk of Infection

Preventing the Spread of E. coli

One of the best way to prevent the spread of E. coli to other people is to maintain proper hygiene. Always wash and scrub your hands carefully with soap and water after you:

  • Use the bathroom
  • Change a diaper
  • Come into direct contact with an animal or its environment, such as the enclosure of a petting zoo or a stable
  • Before touching someone’s mouth or any object that will go into someone’s mouth, including food and a pacifier (2)

In order to actually kill E. coli, wash hands vigorously for a minimum of 20 seconds, the equivalent of singing “Happy Birthday” twice. Contrary to popular belief, warm water is not a must when it comes to killing bacteria and germs; any temperature will do. But don’t forget to always wash the backs of hands, wrists, between the fingers, and under fingernails as well. After hands are dry, use a clean towel to turn off the faucet. (4)

Note that using hand sanitizer does not yield the same protective results as washing hands with warm, soapy water. In fact, the U.S. Food and Drug Administration (FDA) has not approved the use of any hand sanitizer products for preventing an infection from E. coli. (5)

If you’re at a restaurant, there isn’t much you can do to prevent food poisoning from E. coli, aside from sending back any meat that looks like it wasn’t cooked completely, such as pink hamburger meat. But there are a number of steps you can take at home to reduce your risk of getting an E. coli intestinal infection:

  • Cook beef thoroughly. To kill E. coli, steaks and roasts need to be cooked to an internal temperature of at least 145 degrees F; ground beef requires a minimum internal temperature of 160 degrees F.
  • Rinse all fruits and vegetables. These should be rinsed until no visible grime or dirt is left on the produce. Be sure to also wash fruit like melons. When you cut into, say, a cantaloupe, you can drag surface E. coli through the fruit, contaminating the inside.
  • Avoid cross-contamination. Separate raw meats from produce, using different cutting boards and knives when preparing them. Always wash hands, utensils, counters, serving trays, and cutting boards after they’ve been in contact with raw meat. And don’t put cooked meat back on the same plate it was on before it was cooked. (2)

Understanding the Signs of Infection

One of the best ways to avoid spreading your gastrointestinal-related E. coli illness to others is to understand what signs and symptoms indicate that you actually have an infection. These common symptoms include:

  • Severe or bloody diarrhea
  • Nausea, with or without vomiting
  • Severe stomach cramps
  • Fatigue
  • Low-grade fever (a rare symptom)

But keep in mind that you may still have pathogenic E. coli in your system even if you do not experience any symptoms. In fact, most people with a shiga toxin–producing (STEC) E. coli infection — the most common gastrointestinal-related E. coli infection — don’t feel ill until three to four days after consuming something that contained the bacteria.

It’s important to contact your physician if you experience diarrhea that lasts for more than three days, or if your diarrhea is accompanied by high fever, blood in your stool, reduced urine output, or excessive vomiting. (6)


E. coli Bacteria

What is E. coli ?

  • E. coli are bacteria that are commonly found in the intestines of humans and animals. There are different types of E. coli; some not harmful to people and some which cause serious illness such as E. coli O157: H7.

How can you get sick from the harmful type of E. coli ?

  • E. coli infections can be spread by many food sources such as undercooked ground beef, unpasteurized apple cider and milk, ham, turkey, roast beef, sandwich meats, raw vegetables, cheese and contaminated water.
  • Once someone has consumed contaminated food or water, this infection can be passed from person to person by hand to mouth contact.
  • E. coli does not survive in the air, on surfaces like tables or counters and is not spread by coughing, kissing or normal, everyday interactions with friends and neighbours.
  • Poor hand washing and improper food handling are factors that lead to the spread of this illness.

How do you prevent E. coli infections ?

  • Cook ground beef thoroughly to an internal temperature of 71°C or until the juices run clear and the meat is no longer pink.
  • Drink only pasteurized apple cider and milk. Never let youngsters sample milk produced directly from the animal.
  • Wash all fruits and vegetables before eating.
  • Thorough hand washing is always a good practice. Make sure hands are washed with soap and water after using the toilet, handling diapers, pets, livestock or before preparing food.
  • Clean and sanitize counter tops and utensils after these have been in contact with raw meats and poultry.
  • Use separate work surfaces and utensils for preparing raw and cooked foods.
  • Keep cold foods at 4°C or lower. Keep hot foods at 60°C or higher.
  • Drink water from a supply intended for human consumption.
  • Do not drink water from open streams and lakes.
  • If ill with diarrhea, avoid preparing or handling food that others will be eating. If employed as a food handler or a health care worker, report any symptoms to your manager.

Frequently Asked Questions

What are the symptoms of infection ?

Stomach cramps, diarrhea (possibly bloody), fever (infrequent), nausea, vomiting. If you or a family member have any of the symptoms, it is important to wash your hands, after going to the bathroom, and before preparing food for others. If possible, have someone who has not been infected prepare the meals.

Can I get it from shaking hands with, or by kissing an infected person ?

E. Coli is not spread by coughing, kissing, or through normal, everyday interactions with friends or neighbours. However, once someone has consumed contaminated food or water, this infection can be passed from person to person by hand to mouth contact. Poor hand washing and improper food handling are factors that lead to the spread of this illness.

What should I do if symptoms persist ?

Anyone who shows symptoms of E. coli should see their physician immediately.

Under 10% of individuals with E. coli infection will develop Hemolytic Uremic Syndrome (HUS). HUS is a serious complication of E. coli infection that may lead to kidney failure. Symptoms of HUS may include a decrease in the amount of urine produced, swelling in the face, hands, and feet, paleness of the skin, irritability and fatigue. Young children (especially under 5 years of age) and the elderly are most at risk for HUS. It is important to watch for the signs of HUS even after diarrhea has stopped. Anyone with these symptoms should see their physician immediately.

What is the treatment ?

Generally, an E. coli infection must run its course. Antibiotics and antimotility medications are not recommended and may increase the risk of complications.

Who can tell me more about E. coli Bacteria ?

Contact your local public health unit for more information.

Facts about E. coli

For the latest information on the *2011 E. coli outbreak in Germany

see our news section, or for advice on food safety see our Live Well section*

Over the weekend a number of news sources have reported on an outbreak of E. coli infection in children in the UK. The outbreak has been linked to a children’s farm in Surrey and all the infected children are under 10 years old. According to BBC News, 36 cases have so far been reported._ The Times_ report focused on the number of children that the farm may have put at risk, estimating that this number may in the thousands because the farm was allowed to remain open for two weeks after it first “fell under suspicion”.

This weekend a press release was issued by the Health Protection Agency (HPA), an independent organisation set up by the government to protect the public from health threats. It says that the farm is now closed to visitors while the HPA investigates the outbreak. Of the 36 children affected, 12 are reported to currently be in hospital with complications from their infection, with three children considered to be seriously ill.

What is E. coli?

Escherichia coli (E. coli) is a type of bacteria common in human and animal intestines, and forms part of the normal gut flora (the bacteria that exist in the bowel). There are a number of different types of E. coli and while the majority are harmless some can cause serious food poisoning and serious infection. For example, E. coli bacteria are a common cause of cystitis, an infection of the bladder that occurs when there is a spread of the bacteria from the gut to the urinary system. Women are more susceptible to urinary tract infection by E. coli because of the close proximity of the urethra and the anus.

Some types of E. coli can cause gastrointestinal infections. As the bacteria can survive outside of the body, its levels serve as a measure of general hygiene and faecal contamination of an environment. A common mode of infection is by eating food that is contaminated with the bacteria.

Some E. coli strains produce toxins (Shiga toxins) that can cause severe illness. One common strain called E. coli 0157 produces such toxins and is usually responsible for the outbreaks that are covered by the news. This strain is responsible for the outbreak linked to the farm in Surrey.

What are the symptoms of infection?

The symptoms depend on the site of infection and which type of E. coli is causing the infection. The children infected by the E. coli 0157 strain from the Surrey farm are likely to have had the classic symptoms linked to this strain, that include severe stomach cramps, vomiting, and diarrhoea that may be bloody. The symptoms usually last up to seven days if there are no complications, but some infections can be severe and may be life threatening.

A particular life-threatening complication called haemolytic uremic syndrome (HUS) may develop in 5-10% of people infected with a toxin-producing form of E. coli. This is a severe kidney-related complication that may, in extreme cases, lead to renal failure and the need for renal replacement therapy.

While all ages are at risk, the HPA explains that children may be more vulnerable to severe infections and complications because they cannot tolerate much fluid and blood loss through vomiting and diarrhoea.

How is E. coli treated?

The specific treatment will depend on the type of infection. Cystitis infections are usually self-limiting (they go away by themselves) after two to four days. In some cases a short course of antibiotics may be given.

Intestinal infections by E. coli are not usually treated with antibiotics either. Rehydration is important as a lot of fluid may be lost through diarrhoea. This is the mainstay of treatment and important whether the infection is being managed in hospital or at home. Oral rehydration solutions are particularly helpful in children with diarrhoea. In addition to providing fluids they also replace other important substances lost from the body, including sodium, potassium and glucose.

How can I prevent E. coli?

E. coli infections can be serious so preventing infections is important. The bacteria are usually spread through faecal matter reaching the mouth, so good hygiene is critical in preventing contamination and spread. This is particularly important with regards to going to the toilet or handling or preparing food as consumption of contaminated food or water and contact with infected faeces or animals are common sources of infection.

The usual hygiene rules apply, including the need to wash and dry hands thoroughly after going to the toilet and after touching animals (for example, at farms). Foods should be cooked thoroughly and it is best to avoid unpasteurised dairy products.

Some people have been infected by swallowing water while swimming or playing in lakes or ponds, and so the CDC recommends that swallowing water during these activities should be avoided.

How did these children become infected?

The precise details surrounding the outbreak of the E. coli infection at Godstone Farm in Surrey are currently being investigated. The HPA has published a timeline of the events leading up to the closure of the farm over the weekend.

The first laboratory case was confirmed on 27 August when Environmental Health Officers learned that an infected individual had visited the farm. A further two cases were confirmed around the 1 September. Environmental Health Officers and a Health Protection Agency team visited the farm on several occasions to inspect it and to advise on important hygiene messages.

Between 4 September and 11 September, the HPA received reports of further infections but all had been contracted prior to 3 September when a team inspected the farm and advised on more stringent hygiene measures and cessation of contact with high-risk animals. The HPA assumed that as the cases seem to have been infected before their advice, their control measures were working. On the 11 September, the HPA was informed of a further case arising from someone becoming infected on the 4 September. Based on this report the children’s farm was closed on 12 September.

It is not clear precisely how the children were infected but it is likely to be related to petting the farm animals. Results of the investigation will reveal if this is the case.

While The Times focuses on the children that were put at risk by the delay between the first reported case and the farm closure, the HPA deem their response to be “proportionate and effective” for the scale of the incident up to and including 3 September. The farm is reported to be a busy farm, particularly during the school holidays, when it receives up to 2,000 visitors per day. Only 36 cases of infection have so far been reported.

Analysis by Bazian
Edited by NHS Website

Links to the headlines

20,000 children put at risk by dithering at E. coli farm.

The Times, 14 September 2009

E.coli children ‘seriously ill’.

BBC News, 12 September 2009

Godstone Farm E-coli outbreak: parents’ anger that attraction stayed open

The Daily Telegraph, 14 September 2009

Links to the science

Investigation of cases of E coli 0157 at Surrey Farm.

HPA. September 12 2009

E coli 0157 in Surrey: Update.

HPA. September 12 2009

Understanding E. coli: symptoms, spread, prevention

You can’t see it, smell it or taste it. But food or water tainted with certain strains of E. coli bacteria can leave you fighting for your life, especially if your immune system is compromised or you’re very young or very old.

Seven people died and more than 2,300 others fell ill in Walkerton, Ont., in May 2000, in Canada’s worst-ever E. coli outbreak after the bacteria got into the town’s water supply. The source of the contamination was manure spread on a farmer’s field near one of the town’s wells.

The largest beef recall in Canada was prompted by an E. coli outbreak at XL Foods in Brooks, Alta., in September 2012. In all, 18 people became sick and more than 4,000 tonnes of beef were recalled from across Canada and the U.S.

A common illness

It was the well-known Canadian version, E. coli O157:H7, which contaminated the water system in Walkerton and the XL Foods plant.

While the Walkerton outbreak was unusual, health authorities in Canada normally deal with a few thousand cases of E. coli illness a year. In the U.S., it’s estimated that about 73,000 people a year are sickened by the bacteria and 61 die.

In 2006, tainted spinach from California led to the deaths of five Americans and sickened over 200, including a Canadian woman.

E. coli O157:H7 can contaminate ground beef during the butchering process. (iStock)

In another outbreak, Ontario health authorities in October 2008 investigated an E. coli outbreak linked to a Harvey’s restaurant in North Bay.

In July 2009, President’s Choice-brand steaks, roasts and ground beef products were pulled from store shelves because of possible contamination with E. coli. Undercooked ground beef is one of the most common sources.

In 2012, the outbreaks included Fredericton, N.B. in July and Miramichi, N.B. in April.

While the vast majority of people fully recover from a bout of E. coli within a week to 10 days, some people will spend the rest of their lives dealing with the after-effects of the illness.

What is E. coli and where does it come from?

Escherichia coli, its full name, is a type of bacteria commonly found in the intestines of animals and humans. There are hundreds of strains of the bacterium, but E. coli O157:H7 has been identified as dangerous to people, producing a powerful toxin that can cause severe illness.

This highly magnified image shows a number of Gram-negative Escherichia coli bacteria of the strain O157:H7, which is one of hundreds of strains of this bacterium. Although most strains are harmless, and live in the intestines of healthy humans and animals, this strain produces a powerful toxin, which can cause severe illness. (Janice Haney Carr/CDC)It was first recognized in the U.S. in 1982, when an outbreak of severe, bloody diarrhea was traced to contaminated hamburgers, leading the illness to be dubbed “hamburger disease.”

E. coli O157:H7, E. coli O104:H4 and other deadly strains belong to a family of bacteria that’s evolved since the 1960s, when scientists believe E. coli and another bacteria, shigella, met and swapped genes. This created a form of E. coli that secretes the dangerous shiga toxin.

E. coli O157:H7 can contaminate ground beef during the butchering process. If it is present in the intestines of the slaughtered animal, it can get into the meat as it is ground into hamburger.

How does E. coli spread?

While E. coli is most often found in meat, it is not limited to it. The bacteria are also found in unpasteurized milk and apple cider, ham, turkey, chicken, roast beef, sandwich meats, raw vegetables, cheese and contaminated water.

Bean and alfalfa sprouts have also been recalled because of E. coli contamination.

Fruits and vegetables that grow close to the ground are susceptible to E. coli contamination if, for example, improperly composted cattle manure is used as a fertilizer.

E. coli, salmonella and cryptosporidium can also be found in unpasteurized juice. Children, the elderly and people with compromised immune systems are encouraged to drink pasteurized juice or boil unpasteurized juice before consuming it.

Once someone has eaten contaminated food, the infection can be passed from one person to another person by hand-to-mouth contact. The bacteria are most often spread person to person.

What are the symptoms of E. coli O157:H7?

Symptoms — characterized by severe abdominal cramping — can appear within hours but could also take up to 10 days to show up. Some people may be afflicted with bloody diarrhea or non-bloody diarrhea. seizures or strokes may occur. Frequently, no fever is present.

Some people may show no symptoms at all but can still carry the bacteria and pass it on to people who will become sick.

What are the health effects of E. coli O157:H7?

An E. coli O157:H7 bacterium under a microscope. (iStock)

People who suffer severe E. coli O157:H7 poisoning face a 30 per cent higher risk of high blood pressure or kidney damage, according to a Canadian study released in October 2008.

The seven-year study, which included 2,800 citizens of Walkerton, noted medication has stemmed further kidney damage and long-term complications in children. Researchers also found that 88 per cent of participants rated their health at the end of the study as good to excellent.

In severe cases, people may die.

How is it treated?

In most cases, symptoms clear up on their own within five to 10 days. The use of antibiotics is not recommended because the bacteria creates a toxin in its cell and if you kill the cell with antibiotics the toxin gets released into the bloodstream.

In a small number of cases, E. coli contamination can lead to hemolytic uremic syndrome (HUS), a life-threatening condition that is treated in hospital intensive care units. It kills three to five per cent of people who come down with it. Some people who recover still have to contend with lifelong complications that can include blindness, paralysis and kidney failure.

How does E. coli get in the water?

According to the U.S. Environmental Protection Agency, the presence of E. coli in water is a strong indication of recent sewage or animal waste contamination.

E. coli comes from human and animal wastes. During precipitation, E. coli may be washed into creeks, rivers, streams, lakes, or groundwater. When these are used as sources of drinking water – and the water is not treated or inadequately treated – E. coli may end up in drinking water.

What happened in the deadliest E. coli outbreak?

In summer 2011, a different and mysterious strain of E. coli led to the deaths of 51 people in Germany and one in Sweden and one in the U.S.. It sickened about 4,000 people, most of them in Germany.


This deadlier strain of E. coli, O104:H4, has been particularly virulent in that it has also led to hundreds of cases of HUS.

The source of the E. coli at first eluded health officials, who advised consumers not to eat cucumbers, tomatoes, lettuce or vegetable sprouts – all of which were investigated as possible carriers of the bacteria.

But after more than a month of searching, the problem was traced to sprouts from an organic farm in the northern German village of Bienenbuettel. The farm grows a wide variety of sprouts, including alfalfa, onion and radish, and officials weren’t immediately sure which kind caused the outbreak. Sprouts are often eaten raw in salads and sandwiches.

Then in July, the European Food Safety Authority said one lot of contaminated fenugreek seeds from Egypt was probably the source. Fenugreek leaves are commonly used as an herb and in curry. The seeds are often sold dried, and if they are contaminated with E. coli, the bacteria can survive for years.

E. coli O104 is a shiga toxin-producing E. coli, or STEC, that is especially vicious because it doesn’t take many bacteria to cause infection.

The bug gets into the stomach and then attaches to the intestinal wall and secretes a toxin that destroys red blood cells and shuts down the kidneys.

Once securely inside the gut of one person, the bacteria can then start spreading person to person through the fecal-oral route. That happens when traces of feces on the hands get passed on, which is why hand-washing is so important.

The E. coli outbreak in Europe has mostly affected healthy adults, not children or the elderly.

It seems a higher rate of people progress to HUS from the initial condition of bloody diarrhea, said Brett Finlay, a professor at the University of British Columbia who studies pathogenic strains of E. coli.

How can exposure to E. coli be prevented?

Proper food handling techniques can go a long way toward preventing exposure to E. coli. All ground meats should be cooked thoroughly. You should also:

  • Refrigerate or freeze meat as soon as possible after buying it and then thaw frozen meat in the refrigerator, not on the counter.
  • Place cooked meat on clean plates. Don’t re-use dishes that have been in contact with raw meat.
  • Use a digital food thermometer when cooking ground beef, which should be cooked to an internal temperature of at least 71 C (160 F).
  • Serve cooked meat immediately or keep it hot (60 C or 140 F).
  • Clean and sanitize countertops and utensils after contact with raw meat.
  • Not store raw and cooked food together.
  • When marinating meat, do not use the liquid as a dip or to pour over cooked meat.
  • Drink only pasteurized milk or cider.
  • Drink water from a supply known to be safe. If you have a private well, it should be tested several times a year.

Since most cases of E. coli contamination are passed from person to person, good personal hygiene is critical to protecting yourself:

  • Wash your hands thoroughly and frequently.
  • Don’t handle food if you have diarrhea.
  • Wash raw fruits and vegetables thoroughly before cooking or cutting them.
  • Sanitize food preparation surfaces and utensils.

Anyone known to be infected with E. coli, should not share dishes, cutlery or glasses with anyone. Their towels, face cloths and bedding should be washed separately in hot water and bleach.

E. coli O157:H7 and HUS Fact Sheet

Revised May 2009

Download a print version of this document:
E. coli O157:H7 and HUS Fact Sheet (PDF)

What is it?

Escherichia coli O157:H7 (E. coli O157) is one of hundreds of strains of the bacterium Escherichia coli. Most strains of E. coli are harmless and live in the intestines of healthy humans and animals. However, the O157 strain produces a powerful toxin that can cause severe illness.

What are the symptoms?

Symptoms of E. coli O157 infection include severe diarrhea (often bloody) and abdominal cramps. Most people infected with E. coli O157 do not have a fever or vomiting.

Symptoms usually begin 2 to 5 days after exposure to the bacteria. Sometimes people infected with E. coli O157 have no symptoms at all, but can still pass the bacteria to others.

In some people, especially in children under 5 years old and the elderly, E. coli O157 infections can cause a complication called Hemolytic Uremic Syndrome (HUS). About 2 – 7% of E. coli O157 infections lead to HUS. HUS occurs when the E. coli O157 toxin destroys red blood cells. HUS can lead to kidney failure, neurologic damage, and in some cases, death. Approximately 5 – 10% of HUS cases are fatal.

How long does it last?

Symptoms usually last 5 to 10 days. People with mild symptoms usually recover on their own without treatment. Antibiotics are not helpful for treating E. coli O157 infections, and may even increase the likelihood of developing HUS. Antidiarrheal agents should not be used either.

How is it spread?

E. coli O157 lives in the intestines of healthy cattle and other animals. E. coli O157 can be found in water, food, soil, or on surfaces that have been contaminated with animal or human feces. Family members and playmates of children infected with E. coli O157are at high risk of becoming infected.

People can become infected by:

  • Eating contaminated food, such as:
    • undercooked hamburger
    • raw produce items, such as sprouts and lettuce
  • Drinking unpasteurized milk, juice, or cider.
  • Swallowing recreational water contaminated with E. coli O157 (recreational water includes lakes, streams, rivers, springs, ponds, swimming pools, hot tubs, Jacuzzis, and water park fountains).
  • Contact with farm animals or pets.
  • Touching contaminated surfaces or objects and then touching their mouth or putting a contaminated object into their mouth.
  • Not washing hands after using the bathroom or changing diapers and then eating foods.

What should I do if I have symptoms?

  • Contact your health care provider. Note that antibiotic treatment is not helpful for E. coli O157 infections, and may be harmful in some cases.
  • Wash your hands often.
  • Do not send your child to daycare or preschool if he or she has diarrhea.

How can I prevent E. coli infections?

  • Wash your hands with warm, soapy water for at least 20 seconds
    • After using the bathroom
    • After changing diapers
    • After contact with animals or their environment
    • Before eating
  • Supervise young children to be sure they properly wash their hands.
  • Wash your hands more often when someone in your household is sick.
  • Cook all ground beef and hamburger products to at least 160°F. Do not eat hamburgers if they are pink in the middle.
  • Prevent cross-contamination in the kitchen by washing hands, cutting boards, countertops, knives, utensils, and surfaces with warm, soapy water after handling raw foods.
  • Separate raw meats, poultry, and seafood from vegetables and cooked foods.
  • Wash and/or peel fruits and vegetables before eating them.
  • Do not drink unpasteurized milk, juice, or cider.
  • Clean and disinfect surfaces with household bleach immediately after vomiting or diarrheal accidents.
  • Don’t drink untreated water from lakes, rivers, streams, ponds, or shallow wells

Healthy Swimming Tips:

  • Do not swallow water or get water in your mouth while swimming.
  • Take a shower before and after swimming.
  • Do not swim when you have diarrhea.
  • When swimming, take your kids on frequent bathroom breaks – waiting to hear “I have to go” may mean that it’s already too late.
  • Change diapers in changing rooms, not poolside or on the beach. Wash hands after changing diapers.

E. Coli

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What Are E. Coli Infections?

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
  • unexplained bruises
  • bleeding from the nose or gums
  • extreme tiredness
  • seizures

HUS can be life-threatening and needs to be treated in a hospital.

How Are E. Coli Infections Treated?

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.

Safe food preparation can go a long way toward protecting your family from E. coli infections:

  • Cook meat well until it reaches a temperature of at least 160°F/70°C at its thickest point.
  • Thoroughly clean anything that comes into contact with raw meat.
  • Choose pasteurized juices and dairy products.
  • Clean raw produce well before eating.

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.

Reviewed by: Steven Dowshen, MD Date reviewed: April 2017What is Shiga Toxin-producing Escherichia coli (STEC)?

Escherichia coli (also called E. coli) are bacteria that normally live in the intestines of humans and animals such as cows. Most strains of the E. coli bacteria do not cause illness. However, strains that produce toxins can lead to illness. The most common type of toxin-producing E. coli is referred to as Shiga toxin-producing E. coli (STEC). E. coli O157:H7 is the most common type of STEC, but other types exist.

Who gets STEC?

Anyone can get an STEC infection, but young children, older adults, and those with weakened immune systems are more likely to have severe illness.

How is STEC spread?

STEC has to enter the mouth to cause infection. People and animals infected with STEC shed the bacteria in their feces (stool). The feces can then contaminate surfaces, food, or water. People can become infected by touching contaminated surfaces, getting the bacteria on their hands and then putting their hands in their mouths, or by eating contaminated food or drinking contaminated water. Infected food handlers can contaminate food if they do not wash their hands properly after going to the bathroom and handle food that other people eat. The bacteria can also be spread in settings such as child care centers, where hands contaminated while changing diapers can spread the disease.

STEC has been associated with people eating contaminated products, such as undercooked ground beef, raw produce (e.g., sprouts, lettuce, and spinach), or raw dough or batter, or drinking unpasteurized (raw) milk or juice. It has also been associated with people swimming in water that has been contaminated with feces. Animal-to-human spread can occur by touching contaminated surfaces or animals (e.g., at agricultural fairs, petting zoos, or farm visits) and then putting hands in the mouth.

What are the symptoms of STEC infection?

Some people who are exposed to STEC do not become ill. Others develop stomach cramps and bloody diarrhea. Symptoms can also include vomiting, fever, and chills. In severe cases, the infection can damage organs, such as the kidneys.

How soon after exposure do symptoms appear?

Symptoms can appear anywhere from one to ten days after exposure, but usually appear around three to four days after exposure.

How is STEC diagnosed?

Special laboratory testing of a stool sample is needed to confirm that a person has been infected with STEC.

What is the treatment for STEC?

Persons with diarrhea should drink plenty of liquids to prevent dehydration. Most people get well within one week without being seen by a physician, but it is important for anyone with bloody diarrhea to seek medical attention. Antibiotics or drugs that stop diarrhea (e.g., Imodium) should not be used.

How can STEC infection be prevented?

STEC infection can be prevented by taking the following precautions:

  • Never eat rare or undercooked ground beef.
  • Cook ground beef and pork to a minimum internal temperature of 160°F.
  • Keep raw meat separate from ready-to-eat foods.
  • Wash hands, counters, utensils, and plates after contact with raw mea.t
  • Always refrigerate meat products.
  • Never leave raw meats at room temperature.
  • Do not drink milk, milk products, fruit juices, or ciders that have not been pasteurized.
  • Always wash raw fruits or vegetables before eating.
  • Always carefully wash hands before and after preparing foods.
  • Wash hands after animal contact and after visiting farms, petting zoos, and agricultural fairs.
  • Always carefully wash hands with soap and warm water after using the toilet or changing diapers.
  • Clean and disinfect diapering areas, toilets, potty chairs, toys, etc. at least daily and when soiled.
  • Make sure children wash their hands carefully, especially after using the toilet or touching animals.
  • Do not use public swimming facilities while having diarrhea.
  • Avoid swallowing water from a swimming pool or other recreational bodies of water.

How long can an infected person carry STEC?

An infected person can spread the bacteria to others for as long as the bacteria remain in the stool (usually one week, but up to three weeks in children).

Should an infected person be excluded from work or school?

It is best to stay home when you have diarrhea. The health department will give advice on each situation in which the person with STEC infection is a food handler, health care worker, child care worker, or child care attendee. Some people might not be allowed to go back to child care or work until two stool specimens test negative for the bacteria.

How can I get more information about STEC?

  • If you have concerns about STEC, contact your healthcare provider.
  • Call your local health department. A directory of local health departments is located at
  • Visit the Centers for Disease Control and Prevention website at

September 2018

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