E. coli (Escherichia coli)

Overview

E. coli (Escherichia coli) is a group of bacteria present in the human intestines. While otherwise deemed harmless, strains like E. coli O157:H7 can cause infections and severe illnesses, triggering symptoms like watery and occasionally bloody diarrhoea, fever, fatigue, vomiting, etc. An E. coli infection may develop in the urinary tract, GI tract or other body parts. STEC is the strain of E. coli that holds a record of having caused severe illnesses.

Contaminated water, undercooked meat or raw, unwashed vegetables are all categorised under 'improperly handled foods/drinks' and can expose people to illnesses caused by E. coli. While the average individual recovers from an E. coli infection within a week, the condition can worsen in children or older people.

What is E. coli Infection?

E. coli naturally lives in the intestines of healthy people and animals. This category of naturally occurring bacteria helps the individual digest food easily and also produce vitamins needed by the body to thrive.

However, some strains of E. coli cause illnesses, like gut and urinary tract infections, painful diarrhoea, sepsis and in severe conditions, pneumonia and other life-threatening diseases. For example, the Shiga toxin-producing E. coli infection can cause HUS (Hemolytic Uremic Syndrome), which in turn, may lead to kidney failure or even death.

People with poor immunity systems, individuals aged below 5 years or above 65 years and ones travelling internationally often (at risk of carrying and causing the outbreak of illness-causing E. coli), are more prone to E. coli infections.

Types of E. Coli Infections

While most E. coli strains are harmless, there are certain strains which cause mild to severe degrees of illnesses in individuals. Here are the 6 types of E. coli that cause diarrhoea and other nagging symptoms in people:

ETEC (Enterotoxigenic Escherichia coli)

This type of E. coli is responsible for travellers' diarrhoea. An outbreak of the ETEC is mostly recorded in areas of poor sanitation, spread through contaminated food and water.

EAEC (Enteroaggregative Escherichia coli)

EAEC is another source of travellers' diarrhoea, causing acute diarrhoea. However, the usual accompanying symptoms of fever and vomiting are not recorded here.

EPEC (Enteropathogenic Escherichia coli)

EPEC mostly affects children and babies, with nursing and daycare places being more prone to its outbreak. It can be found in food and water, owing to poor sanitation efforts which do not meet the hygiene standard mark.

EIEC (Enteroinvasive Escherichia coli)

This type of E. coli may cause bloody stools and severe stomach pains. Fever, vomiting and mucus-filled stools are also notable symptoms. EIEC can be found in raw vegetables and milk, undercooked meat and poorly handled food in general.

EHEC (Enterohemorrhagic Escherichia coli)

EHEC is also known as STEC (Shiga toxin-producing Escherichia coli). It can cause mild to very painful diarrhoea, even characterised by bloody stools. It can also cause life-threatening diseases like HUS leading to kidney failure and other severe conditions. This type of E. coli damages the lining of the affected individual's intestine. EHEC may be found in raw milk, vegetables fertilised with STEC/EHEC-containing manure, undercooked beef, etc.
DAEC (Diffusely adherent Escherichia coli)

The strain of E. coli is rather rare, mainly affecting children below 5 years of age (pre-school). It causes diarrhoea and vomiting in affected children.

Symptoms of E. Coli Infection

While E. coli symptoms are usually experienced within 3 to 4 days of being infected, they may show up any time within 2 weeks. Some common symptoms include watery diarrhoea, stomach pain, tenderness and cramps, bloody stools, nausea and fatigue. A lot of people also get fevers and experience chilling shudders.

In severe cases, people may develop hemolytic uremic syndrome (HUS), a rather serious condition. The symptoms associated with it include reduced urges to urinate, easy bruising or swelling and getting quickly tired.

Causes of E. Coli Infection

Certain strains, like the O157:H7 E. coli, produce powerful toxins which damage the inner lining of the small intestine. If this strain of E. coli is ingested, even in small amounts, the individual develops an infection/illness.

Eating improperly handled foods can lead to exposure to the dangerous strains of E. coli. Indulging in ground beef that has been undercooked can lead to grave health problems. Unpasteurised milk is also unsafe if you’re taking precautions against E.coli.

Uncontrolled cattle may run off into grounds that are home to fresh produce, contaminating them in the process. So, fresh produce may also cause E. coli infections in individuals who consume such foods.

Contaminated water is another major source of E. coli. Water may get contaminated upon coming in contact with human or animal stools. Thus, engulfing a mouth full of water from the stream, river or even swimming pools may serve as a cause of E. coli infections.

E. Coli Infection Diagnosis and Tests

E. coli diagnosis includes the examination of a sample of the infected person's stools at the laboratory. This test checks for the presence of E. coli bacteria in the sample. Further, the bacteria may also be cultured to determine the type of E. coli strain, producing toxins. Upon identification, the plan of action shall be traced accordingly.

Treatment of E. Coli Infection

As there are no specific medicines to cure E. coli at once or relieve its symptoms. Rest and drinking ample amounts of fluids are the major recommendations made, so the infected person can heal faster. While rest can relieve the individual of the fatigue commonly experienced as a symptom of the infection, drinking enough water shall help remain hydrated and make the flushing out of toxins process much easier.

Healthcare professionals recommend avoiding antidiarrheal medication as it will only slow the digestive system down. This, in turn, shall create bloating problems and add to the pain already experienced by an infected individual. If one is diagnosed with a severe form of E. coli, he/she is hospitalised. The treatment regimen shall consist of blood transfusions, kidney dialysis and IV fluids - as and when necessary.

Preventive Measures for E. Coli Infection

Efforts to improve sanitation in every corner shall serve as an effective preventative measure for E. coli infection. For example, washing one’s hands and maintaining cleanliness within food preparation areas are major steps towards boosting sanitation efforts. Apart from that, cooking and serving meals at proper temperatures, avoiding unpasteurised milk and other beverages, and being mindful about indulging in meat, shall all help.

To avoid coming in contact with contaminated water, it is recommended that one undertakes the necessary protective precautions before diving into public swimming pools or other local water bodies. If one deals with animals, they must do it with utmost care. Finally, parents should keep their children away from the daycare centres to avoid the possible outbreak of an E. coli infection.

Myths and Facts Related to E. coli

Here are some myths attached to E. coli and the facts to prove them wrong:

Myth 1: All E. coli Are Harmful for the Body
Fact: Not all E. coli strains are harmful to the body. E. coli is naturally present in the human intestine. Only certain strains, including the O157:H7 E. coli, can trigger illnesses in people.

Myth 2: Vegetarians Will Not Get E. coli
Fact: Vegetables can also get contaminated upon coming in contact with water that may have been left out in poorly sanitised areas. Improper handling of foods can cause their exposure to dangerous E. coli strains. Thus, vegetarians are not completely safe from illnesses only because they do not consume beef.

Myth 3: If I have E. coli, I will have to get hospitalised
Fact: Most individuals with E. coli do not have to get hospitalised. Instead, they can be treated at home. Getting enough rest and drinking adequate water shall speed up the recovery process.