Escherichia coli infection

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at June 25, 2016
StartDiseasesEscherichia coli infection

E. coli infections (or Escherichia coli infections) cause serious flu-like symptoms, and outbreaks are responsible for food recalls and restaurant shutdowns. If not treated correctly or affects individuals with weakened immune systems, the infection may become serious and even life-threatening.


Definition & Facts

The Escherichia (E. coli) bacteria are very common, normally living within the gastrointestinal tract of healthy mammals, including people. There are many varieties of E. coli bacteria, and most are either harmless or healthy. However a few strains of E. coli, such as Escherichia coli O157:H7, can create a bacterial infection in the intestines and cause symptoms such as severe abdominal cramping, diarrhea, and vomiting.

Some cases of E. coli infection may progress to kidney failure, possibly resulting in death. Other strains of the bacteria can cause different types of issues, such as urinary tract infections. Most people contract this bacteria from contact with people or animals carrying it, or by eating or drinking food or water that was contaminated or not prepared properly.

Symptoms & Complaints

The symptoms of E. coli infection usually begin to develop two to four days after coming into contact with the bacteria, although in some people it develops almost immediately or takes several days. The characteristic signs and symptoms of E. coli include:

Those who experience E. coli infections may experience some of these symptoms. However, symptoms as serious as blood in the urine or stools, along with a high grade fever are rare and should be taken very seriously.


Common causes of E. coli infection usually involve some sort of improper food handling or drinking from a contaminated water source. Meat that is not cooked entirely, especially ground beef, can contain the bacteria if it was in the animal before it was slaughtered, as can unpasteurized milk. Sometimes even fresh produce sold by farms, like lettuce or squash, can carry the bacteria on them.

A person does not necessarily need to drink contaminated water to get the infection since swimming in it or simply having the water splashed into an opening such as the eyes, nose, or mouth is enough for the bacteria to enter the body. If someone were to not wash their hands after a bowel movement, that bacteria can easily spread to whatever they touch.

E. coli can also be spread to a healthy person by means of contact with another person or animal that is carrying the bacteria. Animals are especially at risk of carrying the infection, making those who work with them on a daily basis especially vulnerable to contracting it.

Diagnosis & Tests

Professional diagnosis of an E. coli infection is usually not necessary, as the infection most commonly passes before professional treatment is needed. Home diagnosis can also be difficult because the symptoms of E. coli infections can be easily confused with several common illnesses like other types of food poisoning, stomach flu, or other harmful bacterial infections. Because of this, it may be helpful to write down and keep track of one's symptoms as they arise. This can be helpful to a doctor in diagnosing and treating a patient’s illness.

In cases presenting severe symptoms of a possible E. coli infection, diagnosis is recommended, a laboratory test is needed. A doctor will take a patient’s stool sample and send it to a laboratory to test for the presence of E. coli, especially the specific toxic strains such as O157:H7.

Treatment & Therapy

E. coli infections are highly resistant to antibiotics; therefore there is little help hospitals can provide besides basic care until the infection has passed. In the rare cases in which a patient with an E. coli infection requires professional care, steps may be required to insure no permanent damage to the kidney is done.

Usually, E. coli infections are treated at home like many common illnesses. Getting plenty of rest is important, as is drinking large amounts of fluids to keep from becoming dehydrated. As the infection usually causes lack of hunger, it is also important to slowly add foods back into the diet, sticking with low-fiber foods like crackers or eggs at first. Some foods like dairy products and foods with high amounts of fat or fiber should be avoided as they can cause the symptoms to worsen.

Unlike the symptoms of more common food poisoning, the symptoms of E. coli infection may require up to a week of treatment before improvement begins. If serious symptoms like blood in bowel movements or urine or fever should arise, a doctor should be contacted. Those suffering from these symptoms for over a week with little to no sign of improvement should also seek professional medical advice.

Young children, as well as the elderly, should be cared for with extra vigilance as they are more prone to developing life-threatening kidney problems including organ failure. Hemolytic-uremic syndrome is a condition that develops in children with E. coli infection and causes the kidneys to stop being able to filter the blood. The toxins produced by the bacteria kill off red blood cells which then clog the glomeruli, which are the parts of the kidneys that filter blood.

Prevention & Prophylaxis

Preventing E. coli infections is possible. Since a large amount of the bacteria is transferred from animals to humans either through physical contact or not preparing food correctly, washing hands often and preparing meat safely are simple but effective measures to prevent the illness. This includes thoroughly washing raw produce as well, as the E.coli bacteria in farm animals can make its way onto the produce sold in the grocery store.

Usually, less control is available over one’s water supply, but those with home wells should get their water treated regularly and any suspicious water should be boiled before consumption in order to kill off any E. coli bacteria.