E. coli are mostly harmless bacteria that live in the intestines of people and animals and contribute to intestinal health. However, eating or drinking food or water contaminated with certain types of E. coli can cause mild to severe gastrointestinal illness. Some types of pathogenic (illness-causing) E. coli, such as Shiga toxin-producing E. coli (STEC), can be life-threatening.
People infected with pathogenic E. coli can start to notice symptoms anywhere from a few days after consuming contaminated food or as much as nine days later. Generally, the symptoms include severe stomach cramps, diarrhea, fever, nausea, and/or vomiting.
The severity or presence of certain symptoms may depend on the type of pathogenic E. coli causing the infection. Some infections can cause severe bloody diarrhea and lead to life-threatening conditions, such as a type of kidney failure called hemolytic uremic syndrome (HUS), or the development of high blood pressure, chronic kidney disease, and neurologic problems. Other infections may have no symptoms or may resolve without medical treatment within five to seven days.
Due to the range in severity of illness, people should consult their health care provider if they suspect that they have developed symptoms that resemble an E. coli infection, including HUS, but even healthy older children and young adults can become seriously ill.
People of any age can become infected with pathogenic E. coli. Children under the age of 5 years, adults older than 65, and people with weakened immune systems are more likely to develop severe illness as a result of an E. coliinfection. However, even healthy older children and young adults can become seriously