Also known as E. coli

1. Escherichia Coli Also known as E. coli

2. Presentation by: Katie Langlitz

3. History • In 1885, Dr. Theodor von Escherich, a german pediatrician and bacteriologist, first discovered this species in the fecal matter of healthy individuals. He called it bacterium coli commune, due to the fact it is found in the colon. It can also be found in the healthy human intestinal tract and comes in multiple forms. One group of E. coli produces a powerful toxin that damages the lining of the small intestine. Early classifications of prokaryotes placed these in a handful of genera based on their shape and motility. • This bacterium was later reclassified as Bacillus coli in 1895 and then later reclassified again as Escherichia, named after its original discoverer Dr Theodor von Escherich. • E. coli was thought to have originated in its first strains/forms about 102 million years ago (WOW!).

4. Case Study Sandy woke one morning with an upset stomach but thought nothing of this discomfort and proceeded on with her day. As the day progressed, she began to experience severe abdominal cramping followed by a low grade fever, nausea, vomiting, and diarrhea. This persisted for several hours before she was taken to the emergency room. Upon arrival, they drew her blood for testing, and collected and tested a stool sample. Results determined that Sandy had contracted a strain of E. coli. After recounting the , she pinpointed the assumed source of the infection; Sandy and her family had gone out for a quick bite to eat at the local taco bell three nights prior where she ordered a few soft tacos which she had initially thought the ground beef to have been slightly rare. The infection lasted about a week and unfortunately, doctors recommended that she let the infection run its course. The use of antibiotics may increase the risk of developing post-diarrheal hemolytic uremic syndrome. The best recommended action for Sandy was to stay hydrated and full of nutrients. She was fully recovered two weeks later.

5. Characteristics • Pathogen Type: E. coli is a bacterium. • Size: E. coli is about one-hundredth the size of a human cell (about a micron long and one-tenth of a micron wide). • Shape: E. coli has a distinctive, capsule shape. • Motility: This bacterium is highly motile. Some strains have flagella or pili that allow the bacteria to move and attach to human cells. • Staining Characteristics: E. coli is a gram negative bacterium meaning it has a thin wall of peptidoglycan and an outer membrane containing lipopolysaccharide appearing pink under a microscope after the gram stain process is complete. • Culture Characteristics: This bacterium grows as fermenting colonies; some beta hemolysis upon initial isolation. • Growth/Metabolic Characteristics: E. coli can grow in the presence or absence of oxygen, meaning it is a facultative anaerobe.

6. Characteristics continued Virulence Factors • Has a distinctive capsule shape that allows for protection and prevention of phagocytosis. • These bacteria commonly live in the intestines of people and animals. They are typically not harmful to the host unless absorbed into the tissues. • Bacterial adhesion onto mucosal or urothelial cells is important in determining bacterial virulence. • Two closely spaced membranes protecting the cell. • Flagella or Pilli that help the bacteria move about the cell and attach to human cells. • Inside the membrane is a cytoplasm, made up of millions of enzymes, sugars, ATP and other molecules floating freely in the liquid. • E. coli bacteria contain shiga-like toxins that inactivate ribosomes of eukaryotes blocking mRNA translation causing cell death.

7. Pathophysiology • The most common symptoms seen in most strains of E. coli are: • bloody diarrhea • stomach cramps • nausea • vomiting • However, some strains of E. coli can cause severe anemia, kidney failure, or urinary tract infections. • Once a person comes in contact with the E. coli bacterium, the bacteria rapidly multiply in the large intestine and bind tightly to cells in the intestinal lining. Most common in young children and older adults, some strains of E. coli can lead to hemolytic uremic syndrome, a condition affecting the kidneys leading them to shut down which can be deadly if not treated immediately.

8. Pathophysiology continued This snug attachment to cells in the intestinal lining aids in facilitating absorption of the toxic bacteria into the small capillaries within the bowel where it attaches to Gb3 receptors. This inflammation caused by the toxin is believed to be the cause of hemorrhagic colitis. This is the first symptom of E. coli, characterized by the sudden onset of abdominal pain and severe cramps followed within 24 hours by diarrhea. The first of these symptoms occur within 2-5 days after ingestion of E. coli. The incubation period may be as broad as 1-10 days.

9. Mode of Transmission Escherichia coli can be directly transmitted in the following ways: Contaminated Food; most commonly ground beef, unpasteurized milk, and fresh produce. Contaminated water, animals, and humans (i.e. personal contact) are other modes of transmission. E. coli lives naturally in the intestines of humans and animals and does not cause harm. However, if a person ingests food contaminated with E. coli, it can cause harm to that person if the bacteria gets into the tissues. A person can get sick from products contaminated with E. coli if the food or water comes into contact with the feces from a human or animal and becomes ingested. It is very important to wash vegetables, fruits, cooking meats thoroughly, as well as washing your hands after using the restroom to prevent contamination between yourself and others.

10. Diagnostic Process Escherichia coli is usually confirmed by the detection of the bacteria in a stool specimen collected from an infected individual. This bacteria can also be cultured in a laboratory to confirm the diagnosis and identify specific toxins and forms of E. coli. Most hospital professionals such as physicians, nurses, and laboratory technicians know to test for these particular bacteria, especially if the infected individual has bloody diarrhea.

11. Prevention and Treatment In most cases of E. coli, infected individuals will have an infection that lasts about a week and will then resolve without any long term problems. Antibiotics typically do not improve the illness, and some medical researchers believe that these medications can actually increase the risk of developing post-diarrheal hemolytic uremic syndrome (HUS) which poses many more symptoms and complications. Apart from good supportive care as far as paying close attention to hydration and nutritional needs, there is no specific therapy to treat the symptoms of E. coli. Since almost all cases of E. coli come from the direct contamination of food to people, it is very important to be aware of the foods you eat and how they are prepared.

12. Prevention and Treatment continued The following methods are extremely important methods of preventing illness and infection. • Be careful to avoid cross contamination when preparing and cooking food, especially if beef is being served. • Wash your hands before and after eating. Before eating at a restaurant, you may want to check the restaurant report rating for hygiene to ensure they are rated high among surveyors. • Make sure meats have a core temperature of at least 160 degrees Fahrenheit for at least 15 seconds to ensure any contamination of meat has been killed. • Do not allow children to share bath water with anyone who has diarrhea or the stomach flu. Keep any toddlers still in diapers out of bodies of water such as swimming pools, lakes etc. • Wear disposable gloves when changing diapers of any children with diarrhea as children with E. coli may not have bloody diarrhea but are still very infectious.

13. E. coli Outbreaks In the United States in 2003, contaminated food caused about 48 million illnesses, 128,000 hospitalizations and 3,000 deaths annually. These are the results of all contaminations combined; luckily E. coli contaminations have greatly decreased from previous years and have since decreased significantly. In the U.S., it is estimated that there are 73,000 cases of E. coli each year annually, approximately 2,000 are hospitalized, and 60 people died from infections from E. coli. Complications from this infection account for less than 1% of all food borne illnesses. The most common food borne illness is salmonella, followed by E. coli. In Oregon, the average number of cases of E. coli increased from 83 in 2009 to 118 in 2010.

14. Why is this important to study? Food borne illnesses, including E. coli, have been a major problem in our country for many years. Although many cases on infected individuals return to their normal healthy state after the infection has run its course, there are some cases in which patients succumb to the illness. It is very important to continue education and research on preventing and treating the spread of E. coli. With the rise in infection over the last few years, we need to continue efforts to treat and prevent future encounters with this particular bacteria. One area to begin in the area of prevention involves the FDA. If the FDA continues to take measures to ensure that restaurants and food providers are taking every measure possible to avoid contamination, we will see a great decline in the abundance of infections.

15. References Marler, Bill. 2010, October 17. E. coli Lawyer and E. coli Attorney-18 years of experience.http://www.ecoliblog.com/e-coli-legal-cases/ This website has some great references on statistics of E. coli and annual cases of the infection. Davis, Charles Patrick. E. coli 0157:H7 (Escherichia coli 0157:H7 infection). http://www.medicinenet.com/e_coli__0157h7/article.htm This website provided a great description for E.coli bacteria as far as staining techniques, structures, ability to survive in environments and provided some great pictures used in the slides as well. Brain, Marshall. How Cells Work. http://science.howstuffworks.com/environmental/life/cellular-microscopic/cell1.htm This website had a great article describing the shape, size and structure of E. coli and also provided a great comparison to human cells. WebMD. 2010, June 14. E. Coli Infection- Topic Overview. http://www.webmd.com/a-to-z-guides/e-coli-infection-topic-overview WebMD has always been a source I use for medical information. This provided a general overview of E. coli such as symptoms, treatment, prevention, as well as structure, function and pathophysiology. MarlerClark. E. coli- E. coli bacteria: what are they, where did they come from, and why are some so dangerous?http://www.about-ecoli.com/ This website providing a lot of information about methods of prevention and treatment of E. coli. It gives a step by step list of different actions to take in regards to preventing future encounters with this bacteria.