Over the past few months, we've heard about outbreaks of E. coli.  These types of outbreaks seem to happen periodically, but not all E. coli bacteria are harmful.  Here is everything you need to know about what E. coli bacteria is, when it is harmful, and how you should be concerned about it.

What is E. coli, anyway?  E. coli is short for Escherichia coli which are bacteria that live in the intestines of both humans and animals alike.  Most E. coli bacteria are harmless and actually help the body with waste processing and food absorption.  The bacteria that cause illness in humans are a type of mutated E. coli bacteria that can live in animals known as Shiga toxin producing Escherichia coli or STEC.  It is the Shiga toxin secreted by these type of E. coli that make people sick. 

How does it make me sick?  Common symptoms of STEC infection include severe or bloody diarrhea, severe stomach cramps, fatigue, low grade fever,  and nausea with or without vomiting.  The symptoms can sometimes vary depending on the strain of STEC, some strains producing more severe symptoms than others.  The O157:H7 strain of STEC is the one most commonly known for severe outbreaks in the United States.  One of the more severe symptoms of this strain is a potentially life-threatening complication known as hemolytic uremic syndrome (HUS) which is a type of kidney failure.  The symptoms of HUS generally begin to show about 7 days after diarrhea symptoms begin, just when the diarrhea is starting to improve.  Most people affected with HUS recover within a few weeks, but in some cases it can cause permanent kidney damage or even death.  Other strains of STEC can cause symptoms such as urinary tract infections or respiratory illness including pneumonia.  The O26 strain (which was responsible for the recent outbreak at Chipotle restaurants) causes similar symptoms to the O157:H7 strain, but is less likely to lead to HUS or other kidney problems. Other strains include O104:H4, which can cause symptoms as severe or worse than the O157:H7 strain, and O26, O145, O111, and O103 which often have less severe symptoms and less risk of long term kidney damage.

What can I do to treat it if I get sick?  Most of the time, illness caused from STEC infection will run its course in 5-10 days.  Even though E. coli is a bacteria, antibiotics are not recommended for treatment.  Remember, the illness is caused from the powerful toxin secreted by the E. coli bacteria, not the bacteria itself.  Killing the bacteria with antibiotics could release more of the toxin into your system potentially putting you at greater risk of developing HUS and seriously damaging your kidneys.  For normal symptoms of STEC infection the best thing to do is to stay hydrated to offset the loss of fluids caused by diarrhea or vomiting.  If  you experience symptoms such as high grade fever or vomiting that is so severe you cannot keep liquids down and pass very little urine, see your healthcare provider.  If symptoms of HUS arise, such as decreased frequency of urination, extreme fatigue, or losing pink color in cheeks or lower eyelids, you may need to be hospitalized.  Young children, the elderly, and those with a weakened immune system are most likely to be at risk of HUS or severe complications from infection.

How did I get exposed to E. coli in the first place?  This part gets a little gross.  STEC lives in the feces of animals and infected people and is spread to other people when they swallow small amounts of feces that have the STEC living in it.  I know, I know…you don't eat poop, but I warned you it was going to get a little gross.  A lot of times STEC outbreaks start from food that has been contaminated with the bacteria.  Meat can sometimes become contaminated during the butchering process and fruits and vegetables that grow close to the ground can become contaminated if improperly composted manure is used as fertilizer.  The bacteria can also sometimes contaminate unpasteurized milks or juices.  If meats are undercooked or fruits and vegetables are not washed properly, it is possible to spread the bacteria to people who eat the food.  The bacteria is not often spread person to person by kissing, coughing or sneezing, but it can be spread by direct hand to mouth contact or if an infected person does not properly wash their hands before preparing food for another person.   The best way to protect yourself and to prevent the spread of harmful STEC is to practice proper hygiene, especially after using the bathroom, and to properly clean, prepare and cook foods prior to eating them.