Escherichia coli, also known as E. Coli, are bacteria that can be found in the intestines of healthy humans and animals. Most strains of E. Coli are harmless and do not cause disease. However, some types of E. Coli can produce Shiga toxin. This toxin can cause illness with symptoms of stomach cramps, diarrhea (sometimes bloody), and vomiting. Shiga toxin-producing E. Coli (STEC) is the most common type of toxin-producing E. Coli.
Animals or people infected with STEC can shed the bacteria in stool and contaminate food, water, or surfaces with the bacteria. Infections happen when the bacteria are ingested or swallowed. This can happen in several ways, such as:
Symptoms normally begin around three to four days after being exposed to STEC, but it can range from one to 10 days. STEC symptoms can vary and illness can range from mild to severe. Common symptoms include:
Most people will start to feel better in five to seven days. If it does develop, HUS normally appears around seven days after symptom onset and when diarrhea is improving. Symptoms of HUS include:
Diagnosis
STEC infections are normally diagnosed through laboratory testing of a poop sample. Shiga toxin positive specimens must be sent to the Indiana Department of Health Lab for confirmation and additional testing.
Treatment
STEC infections should be treated with supportive therapy, such as hydration. There is also no evidence that treating STEC infections with antibiotics is helpful, and they should not be used since they may increase the risk of HUS. Antidiarrheal agents like Imodium® may also lead to an increased risk of HUS and should be avoided.
Once you or your child start having symptoms of the illness, such as diarrhea, do not attend work (specifically for food handlers, healthcare workers, daycare workers) or attend daycare or school until a healthcare provider or someone from your local health department says you are clear to go back.
If you believe you have STEC and have not yet been treated or spoken to a doctor, please be sure to do so. You should be evaluated by a doctor to confirm that you have STEC, and that you get the correct treatment. You should also respond to requests to be interviewed by your local or state public health department. An investigation will take place for every confirmed case of STEC. It is important that you answer the call from your local or state health department so that other people in your home or near you are not at risk of getting STEC as well. An investigation may also look into your exposures to check if other people are at risk.
Most people infected with STEC recover within five to seven days, but others may not. If not, it can sometimes cause severe disease such as hemolytic uremic syndrome (HUS). HUS is a type of kidney failure associated with STEC infections. These cases are more likely to require hospitalization and may develop into other, more serious health issues . This type of infection is most common in young children under 5 years old and those with weakened immune systems. Although, anyone can develop HUS. Always visit your healthcare provider if your STEC symptoms worsen or do not improve over time.
Approximately 20% of individuals will develop HUS without a prior STEC infection. This is known as “atypical HUS.” To learn more about this, please visit the resource link below.
Page last reviewed/updated: December 2024
