Signs Of An E.Coli Infection

September 7, 2023

Why is it so important to recognize the symptoms associated with an E. coli infection? Escherichia coli, or E. coli, is a common bacteria that lives in the intestines of humans and animals. Most strains of this bacteria are harmless to humans and help the body break down and digest food. However, some strains wreak havoc on the body, and symptoms can range in severity from mild to life-threatening. Death from an E. coli infection is rare but can happen due to kidney failure. Once exposed to E. coli, symptoms can start in as little as twenty-four hours, and typically, the incubation period is between three and four days. Recognizing whether symptoms warrant a visit to the emergency room or simply require rest and rehydration can save a life.


As with many bacterial infections, a fever is an early sign of an E. coli infection. Since most pathogenic bacteria thrive at body temperature, a fever helps to create an environment in which they cannot proliferate. Bacteria cannot survive within the elevated core temperature of a febrile host. Therefore, the infection can begin to be thwarted. This is one of the body's first lines of defense in fighting disease. Fevers that remain below 103 degrees, though sometimes uncomfortable, are generally not of great concern. They are direct proof the body is fighting a foreign invader. Should a patient's temperature rise above 103 degrees, medical attention should be sought.


Another early sign of an E. coli infection is marked by feelings of extreme lethargy, sleepiness, and weakness in the body, and can result from being dehydrated. When the body is dehydrated, blood volume lowers, and the heart must work harder to pump oxygen-rich blood. This explains why lying down can feel like climbing a mountain. Completing simple daily tasks can feel daunting and exhausting when one is suffering from fatigue. Replacing lost fluids and electrolytes slowly to alleviate dehydration, along with getting ample rest, is essential to help mitigate this symptom. Fatigue can be caused by many different factors like poor sleep quality or vigorous exercise. For this reason, it is notable this symptom alone does not always indicate an infection.

Abdominal Pain

Abdominal pain is usually present with an E. coli infection and can be felt from the stomach area to the lower abdomen. Since the infection is in the intestines, the abdomen may be sensitive to touch and pressure. Much like the disease's symptoms, abdominal pain can range from mild to severe. Dull aching can turn into more acute cramping, and pain can intensify when a person tries to eat or drink making it a challenge to restore hydration and nutrients. Depending on pain intensity, a patient may be able to go about easy daily chores or might be restricted to lying in bed.


Diarrhea is almost always present with an E. coli infection. Since the bacteria attack the intestines, it makes sense the body would try to clear them this way. Frequent trips to the toilet are not only painful and exhausting, but they can quickly lead to dehydration, thus exacerbating other symptoms. Consequently, trying to rehydrate too quickly can intensify diarrhea. It is important to let it run its course rather than trying to alleviate it with an anti-diarrheal medication. This medicine slows down the digestive system allowing the bacteria to stay in the body longer. Diarrhea is the body's way of eliminating the bacteria and toxins from itself. Should blood be found in the stool, it is important to see a health care professional, as this is a sign the infection has become more virulent.

Nausea And Vomiting

Nausea and vomiting are sometimes present together with an E. coli infection. Nausea is feeling like you might get sick. Vomiting is regurgitating food from the stomach through the mouth. Though nausea and vomiting often accompany one another, vomiting from an E. coli infection is much rarer than nausea. The fact the disease invades the intestines means it is already too far past the stomach to induce vomiting. Often, vomiting will be present at the onset of infection and will decline as the patient's appetite declines over the course of infection. As noted previously, trying to rehydrate or introduce food too quickly can cause the stomach to eject its contents.

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