Escherichia coli (E. coli) is a bacterium commonly found in the gut of warm-blooded organisms.
Most strains of E. coli are not harmful but are part of the healthful bacterial flora in the human gut. However, some types can cause illness in humans, including diarrhea, abdominal pain, fever, and sometimes vomiting.
E. coli O157:H7 is one of the strains, and produces a toxin known as Shiga. It is one of the most powerful toxins, and it can cause an intestinal infection.
Some 265,000 Shiga toxin-producing E. coli (STEC) infections occur each year in the United States (U.S.). Around 36 percent of these are probably caused by E. coli O157:H7. When a foodborne outbreak occurs, it usually involves a shiga toxin-producing E. coli.
Most people recover within 6 to 8 days, but it can be life-threatening in infants and people with a weakened immune system.
Some other types of E. coli infection can lead to urinary tract infections, respiratory illness, pneumonia, and other illnesses like meningitis.
Fast facts on E. coli
Here are some key points about E. coli. More information is in the main article.
E. coli refers to a wide range of bacteria that can cause various diseases, including pneumonia, urinary tract infections, and diarrhea.
Most strains of E. coli are harmless to humans.
Some strains of E. coli infection can include nausea, vomiting, and fever.
In susceptible individuals, certain types of E. coli infection can lead to kidney failure
Following hygiene rules helps prevent its spread
E. coli infects the intestine and causes symptoms that range from non-presenting to severe.
Symptoms of infection with E. coli 0157 typically appear 3 to 4 days after being exposed to the bacteria. However, symptoms may appear as early as 24 hours or as late as 1 week later.
These can include:
abdominal pain or severe abdominal cramping, often starting suddenly
watery diarrhea, beginning a few hours after the pain begins
bright red bloody stools around a day later, resulting from the toxin’s damage to the intestines
nausea and, in some cases, vomiting
in some cases, fever, usually below 101 degrees Fahrenheit
fatigue, resulting from dehydration and the loss of fluids and electrolytes
Some people have no noticeable symptoms, but they can spread the infection to others.
There is no cure for E. coli O157:H7. It has to resolve itself. Antibiotics are not advised. They may increase the risk of HUS.
Patients should get plenty of rest and drink a lot of water to prevent dehydration.
Over-the-counter (OTC) medications for diarrhea are not recommended, as they can slow down the digestive system, undermining the body’s ability to eliminate the toxins efficiently.
E. coli bacteria are a common cause of urine infections, for example, cystitis. The exit of the urinary tract is near the anus, and so the bacteria can spread from the GI tract to the urinary tract.
Wiping from front to back can help reduce the risk.
Most strains of E. coli are harmless, but some produce a toxin that makes humans sick.
The group of E. coli that includes 0157:H7 produces a potent toxin called Shiga. This toxin can harm the lining of the small intestine.
Humans can become infected by:
Swallowing contaminated water: Tap water in the US is treated and contains chlorine, but some E. coli outbreaks have been caused by contaminated municipal water supplies.