Skip to main content

E. coli outbreaks are fairly common, with an estimated 265,000 illnesses and 100 deaths each year in the US. But this bacteria, and the illness they cause, aren’t something to take lightly.

Not all strains of E. coli can cause illness, but the ones that do can be pretty unpleasant. E. coli can lead to an array of symptoms, from diarrhea to urinary tract infections (UTIs), and is typically spread through contaminated food or drink. So what signs should you look out for, and how can you protect yourself from getting sick with E. coli, especially during a known outbreak?

Keep reading for a quick guide on how to keep yourself safe from this bacterial infection.


Experts Featured in This Article:

Laleh Gharahbaghian, MD, is a clinical professor of emergency medicine at Stanford Health Care.

Nicholaos Bellos, MD, is the national medical director, extended care services, at Quest Diagnostics.


What Is E. Coli?

E. coli stands for Escherichia coli, a type of bacteria “found in the environment, foods, and intestines of people and animals,” according to the CDC. Many types of E. coli are harmless and even beneficial, living in your gut and aiding in digestion while protecting your body from other microbes. Not all strains are so helpful, however. “There are different strains of E. coli, some of which are pathogenic, meaning it causes disease/illness,” says Laleh Gharahbaghian, MD, a clinical professor of emergency medicine at Stanford Health Care. Those pathogenic strains can lead to very severe illness, Dr. Gharahbaghian tells PS, and may even cause death if they get into the bloodstream and go untreated.

E. Coli Causes and Symptoms

You can become infected by pathogenic E. coli by consuming contaminated food or water. “It spreads via the oral-fecal route,” Dr. Gharahbaghian says. That means an E. coli infection can happen when disease-causing strains of E. coli make it from the gut onto surfaces or hands and then into someone’s mucus membranes (like their nose and mouth) or from the gut to the urinary tract.

In many cases of food contamination, E. coli bacteria come into contact with the food (for example, beef or raw vegetables) through farming practices or processing, according to the Mayo Clinic. Fruits and vegetables, in particular, can be contaminated when they’re grown near animal farms, says Nicholaos Bellos, MD, the national medical director, extended care services, at Quest Diagnostics. “Contaminated fecal matter combines with rainwater, and the runoff enters produce fields,” he explains. “This is why it’s important to always wash fruits and vegetables before consuming, even if you’re going to cook them.” (More on that later.) E. coli can also be transmitted person to person, he says, “usually through hand-to-mouth contact, not kissing, coughing, or normal interactions.”

Symptoms of an E. coli infection vary, because different strains cause different symptoms, Dr. Gharahbaghian adds. Symptoms of the most common strains may include:

  • Severe stomach cramps
  • Diarrhea (may be bloody)
  • Vomiting
  • Fever (typically less than 101 degrees Fahrenheit)
  • UTIs, if the E. coli travels from the gut to the urinary tract
  • Meningitis, in rare cases, if the E. coli spreads to the fluid surrounding the brain

E. coli that makes its way into your bloodstream may also cause sepsis and septic shock, “a life-threatening condition that requires immediate antibiotic management,” Dr. Gharahbaghian says. Another rare outcome is a severe GI infection, which can sometimes be fatal, Dr. Bellos says. Another rare complication of E. coli is hemolytic uremic syndrome, a life-threatening form of kidney failure that typically begins with several days of often-bloody diarrhea, according to the Mayo Clinic.

E. Coli Treatment

An E. coli infection may be mild and go away on its own, but others can be severe or life threatening. Most people start feeling sick two to four days after consuming the bacteria (although illnesses can start up to 10 days after exposure), and many will get better within five to seven days, per the CDC.

“This is not a bacteria that you want to ignore,” Dr. Gharahbaghian emphasizes. “It can be strong and cause severe illness if not treated appropriately.” According to the CDC, you should see a doctor for an E. coli infection if you experience:

  • Diarrhea or vomiting that lasts for more than two days
  • A fever higher than 102 degrees Fahrenheit
  • Bloody poop or pee
  • Signs of dehydration or hemolytic uremic syndrome

There is no cure for an E. coli illness. But treatment typically includes drinking water to prevent dehydration and exhaustion, as well as lots of rest. Your doctor may also prescribe antibiotics depending on the strain of E. coli you have, Dr. Gharahbaghian says, either with oral pills or (for more severe infections) through an IV.

Protecting Yourself From E. Coli

A few healthy habits can lessen your risk of getting sick from an E. coli infection.

  • Wash your hands. “The best way to avoid having [E. coli] cause illness is by thoroughly washing hands frequently, especially before eating,” Dr. Gharahbaghian says. The CDC also recommends washing your hands with soap and water (or using alcohol-based hand sanitizer) before and after prepping or eating food; after using the bathroom or changing a diaper; after touching animals; before feeding an infant or toddler; and before touching an infant or toddler’s mouth or anything that goes in their mouth (like a pacifier).
  • Wash fruits and vegetables thoroughly under running water. You can skip this if the product is packaged and says the food has already been washed.
  • Cook meat thoroughly. For beef steaks and roasts, this means cooking to an internal temperature of at least 145 degrees Fahrenheit. For ground beef and pork, this means an internal temperature of at least 160 degrees Fahrenheit. Make sure to use a food thermometer to check the internal temperature.
  • Refrigerate perishable foods within two hours of opening, buying, or preparing. This includes food like meat, seafood, dairy, some types of fruits and vegetables, and cooked leftovers.
  • Thaw food safely. The CDC recommends thawing frozen food in the refrigerator, in cold water, or in the microwave, as thawing food on the counter may allow bacteria to quickly multiply as parts of the food reach room temperature at different times.
  • Avoid cross-contamination of food and food-prep items. Make sure you wash your hands and any other items (like counters, cutting boards, and utensils) after they touch raw meat.
  • Avoid drinking raw milk and unpasteurized dairy products and juices.
  • Avoid swallowing large amounts of water while swimming in pools, lakes, ponds, and streams.
  • Wipe from front to back after urinating. This ensures you don’t push any bacteria (including E. coli) from around your anus and genital region closer to your urinary tract, which can increase your risk of a UTI.

Note that some people are naturally at a higher risk of contracting a foodborne illness, including pregnant people, newborns, children, older adults, and people with weak immune systems (such as people with cancer, diabetes, or HIV/AIDS). That said, anyone can get ill from E. coli. “It’s important to communicate with a doctor if there are concerns,” Dr. Gharahbaghian says, “and to go an emergency department if you’re feeling very ill.”


Maggie Ryan was an assistant editor at PS. A longtime runner and athlete, Maggie has nearly four years of experience covering topics in the wellness space, specializing in fitness, sports, nutrition, and mental health.