E. Coli, Escherichia coli
Escherichia coli (abbreviated as E. coli) are a large and diverse group of bacteria. Although most strains of E. coli are harmless, others can make you sick. Some kinds of E. coli can cause diarrhea, while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses. Some kinds of E. coli cause disease by making a toxin called Shiga toxin. The bacteria that make these toxins are called "Shiga toxin-producing" E. coli, or STEC for short. When you hear news reports about outbreaks of "E. coli" infections, they are usually talking about E. coli O157. Other kinds of E. coli are used as markers for water contamination, so you might hear about E. coli being found in drinking water, which are not themselves harmful, but indicate the water is contaminated.
People of any age can become infected from E. coli. The time between ingesting the STEC bacteria and feeling sick is called the "incubation period." The incubation period is usually 3-4 days after the exposure, but may be as short as 1 day or as long as 10 days. The symptoms of these infections vary for each person but often include severe stomach cramps, diarrhea (often bloody), and vomiting. If there is fever, it usually is not very high (less than 101 degrees F. Most people get better within 5-7 days. Some infections are very mild, but others are severe or even life-threatening.
Very young children and the elderly are more likely to develop severe illness and hemolytic uremic syndrome (HUS) than others, although healthy older children and young adults can become seriously ill. Around 5-10% of those who are diagnosed with STEC infection develop HUS, a potentially life-threatening complication. A person that is developing HUS may experience decreased frequency of urination, feeling very tired, and losing pink color in cheeks and inside the lower eyelids. Persons with HUS should be hospitalized because their kidneys may stop working and they may develop other serious problems. Most persons with HUS recover within a few weeks, but some suffer permanent damage or die.
Infections start when you swallow STEC, in other words, when you get tiny (usually invisible) amounts of human or animal feces in your mouth. Unfortunately, this happens more often than we would like to think about. Almost everyone has some risk of infection. Because there are so many possible sources, for most people health providers can only guess where their infection came from. If your infection happens to be part of the about 20% of cases that are part of a recognized outbreak, the health department might identify the source. Good hand-washing after changing diapers, after using the toilet, and before preparing food is always a smart idea to protect yourself, your family, and other persons from the spread of these and many other infections.