E. coli bacteria comprise a broad group of bacteria that live in the intestinal tract of healthy people and animals. Most of the bacteria are harmless and play an essential role in absorbing certain vitamins, but a few strains of E. coli are responsible for serious food-borne infections. I am sure most of you have heard at some point in your life how someone had an E. coli infection. That is why it would be wise to learn more about these bacteria, their symptoms of infection, and possible treatment.
What are Escherichia coli?
A particularly virulent strain of E. coli can cause severe, bloody diarrhea, kidney failure. and even death. Most cases of E. coli trace back to undercooked ground meat. Although it is not always possible to prevent food poisoning, knowing how E. coli spreads and how to handle food safely can help you avoid infections.
Escherichia coli is the abbreviated name for the bacterium in the family Enterobacteriaceae. Interestingly, E. coli is normally is already present in a newborn infant’s intestines, along with lactobacilli and enterococci, representing the most abundant bacterial flora. The organisms which happily inhabit the intestinal tract as normal flora are enteric bacteria, named after the Greek word enterikos, which pertains to the intestine. The name Escherichia comes from the name of the person Escherich, who isolated and characterized this bacterium first. The presence of Escherichia coli and other kinds of bacteria within our intestines is necessary for us to develop and operate properly, which is why we could say these are somehow “good” bacteria that help us remain healthy, along with other species of bacteria. These bacteria provide us with many necessary vitamins for example.
The bacteria make the vitamins, and we gladly absorb them, so we pretty much depend upon Escherichia coli in our intestines for our Vitamin K and B-complex vitamins. The fetus of any animal is completely sterile, but immediately after birth, the newborn acquires all kinds of different bacteria, which live symbiotically with the newborn and throughout the individual’s life. “Symbiotically” means we help them to live and they help us as well. From the day we are born, we are never without bacteria. However, the helpful bacteria like these are located only in regions of our body directly exposed to the environment. These parts of the body are our intestines, upper and lower respiratory tract, etc. Bacteria should never come into the bloodstream or the tissues inside our body. Although it might sound weird, but it is true that billions of these little critters chugging away, making things we need, helping digest our food, are very important to us.
When are E. coli bacteria bad for us?
Bacteria are somewhat like humans in that certain individual ones are not very nice. We know that some individual humans can be downright dangerous. Therefore, as there are individual humans, so too can different individuals exist among Escherichia coli bacteria. Some of these different strains of bacteria can be harmful to us. Each of us – given the assumption that a human is reading this information – is sort of a strain of the human species, sapiens. We are different because we are genetically different. Since an individual strain of E. coli may exist, this situation means that this particular strain of E. coli is genetically different from the vast majority of E. coli in our intestines. Otherwise, it would not be a different strain of this organism. If this E. coli strain happens to have genetic information for producing something harmful to us, then, we may be in trouble.
Signs and symptoms of an E. coli infection
It is clear already that not all disease-causing Escherichia coli bacteria are equal. One strain, enterotoxigenic Escherichia coli, is a leading cause of diarrhea in children in developing nations. It is also responsible for most cases of traveler’s diarrhea, and is an increasing source of food-borne infection in modern industrialized countries. Enterotoxigenic E. coli bacteria spread in contaminated food including raw fruits and vegetables, raw seafood, un-pasteurized dairy products, and contaminated water. Signs and symptoms include watery diarrhea and abdominal cramping. These symptoms usually last just a few days. The infection normally clears on its own without treatment, and most adults and children have no lasting ill effects after. However, E. coli O157: H7 is different, because this kind produces a toxin that damages the lining of the small intestine, leading to intense abdominal cramps and severe, bloody diarrhea as the main symptom. A patient may have ten or more bowel movements a day, some consisting almost entirely of blood. The marked loss of fluids and electrolytes causes dehydration and fatigue as a serious problem of the E. coli infection. Nevertheless, many people recover completely from the infection in five to ten days, while others, especially older adults, children under the age of 5, and people with weakened immune systems, may develop a serious complication called hemolytic uremic syndrome. This syndrome damages the lining of the tiny blood vessels in the kidneys, sometimes leading to kidney failure. Even with the best of care, including blood and platelet transfusions and kidney dialysis, a few children die every year of hemolytic uremic syndrome as a complication of E. coli infection. Others may have lifelong kidney problems or require long-term dialysis, while yet others develop further complications such as high blood pressure, seizures, blindness and paralysis.
How E. coli bacteria spread
You develop an Escherichia coli infection when you accidentally ingest the bacteria. The most common sources of infection are:
Contaminated food, since Escherichia coli bacteria exist naturally in the intestine of many animals, including cattle. The problem with E. coli is particularly serious in modern feedlots, where animals spend their lives in crowded, filthy conditions. Although beef in general may be contaminated, ground meat is a special concern. This is because grinding combines meat from different animals and transfers bacteria from the meat’s surface to its interior. The bacteria also can spread from one surface to another, which means that bacteria on a cow’s udder or on equipment can end up in milk. Pasteurization kills the bacteria, but raw milk can be a source of E. coli infection. Other foods that can be contaminated with the bacteria include dry cured sausage, salami, alfalfa sprouts, lettuce, and un-pasteurized apple juice.
Contaminated water is a possible way of spreading E. coli as well. Runoff from feedlots can contaminate ground and surface water, including water used to irrigate crops for example. Drinking or inadvertently swallowing untreated water from lakes and streams can cause you to catch an infection with Escherichia coli. The same problem occurs with eating unwashed raw fruits and vegetables. Although public water systems use chlorine, ultraviolet light, or ozone to kill E. coli, some outbreaks links to contaminated municipal water supplies.
Person-to-person contact is a common way of spreading the infection, because Escherichia coli bacteria can easily travel from one person to the next. It happens especially when infected adults and children do not wash their hands properly. Family members of young children with the infection are especially likely to become sick themselves, because children can shed the bacteria in their stools for up to two weeks after the symptoms improve.
How to prevent an infection with Escherichia coli
To prevent the growth of bacteria in your kitchen, thoroughly wash anything that comes in contact with raw meat, including your hands, counters, and utensils. Try to use hot, soapy water, bleach or disinfecting wipes, and never put cooked hamburgers on the same plate you used for raw patties.
You should also order beef cooked medium or well done when eating out. Try to be persistent about getting what you ask for, even if it means sending your food back more than once. Drink pasteurized milk, juice, and cider, knowing that any boxed or bottled juice kept at room temperature is pasteurized, even if the label does not say so. Wash raw produce thoroughly, using plenty of running water, and a scrub brush or a vegetable wash.
Children, older adults and people with weakened immune systems should avoid alfalfa sprouts. Avoid drinking untreated water from lakes and streams, and swallowing water when swimming. It is important to be aware that pool water can be contaminated with feces. You have to make sure that family members, including children, wash their hands after using the bathroom, changing diapers, and before eating.
Treatment of an E. coli infection
Most Escherichia coli infections, even those caused by the infamous Escherichia coli O157:H7, are not life threatening. However, these bacteria can cause serious and even fatal illness in some people. Even if you are not at risk, seek medical advice if your symptoms are severe or persistent; in that case you should have your stool checked for E. coli bacteria. Most cases of traveler’s diarrhea clear up on their own in a few days, although doctors sometimes prescribe a short course of the antibiotic Xifaxan. This drug reduces the number of E. coli bacteria in the gut. When it comes to more severe infections such as O157:H7, no current treatments can cure the infection, relieve symptoms, or prevent complications. For people with O157:H7 infection, resting and having plenty of fluids to prevent dehydration are the best treatment options.