Transcript E coli
Escherichia coli Genus Enterobacteriaceae Species Escherichia coli Morphology Gram Negative Rod Grows as fermenting colonies with some beta hemolysis upon initial isolation Motile Non-pigmented Physical Requirements Temperature Mesophile 10*C, 37*C, 45*C pH Prefer Neutral Environment Oxygen Facultative Anaerobe • Media Glucose Fermentor Oxidase (-) Nitrate Reducer Lysine (+) Citrate (-) Indol (+) Acetate (+) Lactose (+) Source Reservoir Cattle, Humans, Soil, Water Normal Flora Most predominant organism of the Large Intestine Ordinarily Non-pathogenic, but can be opportunistic •Virulence Factor Flagella Fimbriae (Pili) important for coloniaztion of host tissue Exotoxins Major Diseases Caused Clinical Syndromes: 85% of urinary tract infections 50% of primary nosocomial pneumonia in some hospitals Major cause of neonatal meningitis with up to 80% mortality Gastroenteritis (see above and Summary Table below for specific syndromes and virulence factors associated with specific strains) Wound infections Peritonitis: sepsis Urinary Tract Infection Alternate Names : Bladder Infection, Cystitis, UTI Prevention of Cystitis Appropriate hygiene and cleanliness of the genital area may help reduce the chances of introducing bacteria through the urethra. Females are especially vulnerable to this, because the urethra is in close proximity to the rectum. The genitals should be cleaned and wiped from front to back to reduce the chance of dragging E. coli bacteria from the rectal area to the urethra. Coli Enteritis Treatment Cases usually resolve themselves in 1 to 3 days, and no treatment is required. Antidiarrheal medication may delay the elimination of the organism from the digestive tract, and therefore may not be recommended. Rehydration with electrolyte solutions may be necessary if dehydration from diarrhea occurs. People with diarrhea (especially in young children) who are unable to take oral fluids because of nausea may need medical attention and intravenous fluids. People taking diuretics need to be cautious with diarrhea, and may need to stop taking the diuretic during the acute episode, as directed by the health care provider. Dairy products should be avoided, as they can make the diarrhea worse (due to the temporary lactose intolerance that can arise.) How can I reduce the risk of infection from E.coli ? 1. Always clean any surface that has come in contact with raw meat, before any other item is placed on that surface. 2. Always thoroughly wash your hands after handling raw meat, and before you handle any other utensils or other food items. 3. Never use the same plate, tray or utensils for the cooked meat that you use for the raw meat - unless you thoroughly wash the plate, tray or utensils inbetween. 4. Always cook meat, _especially_ ground meat, until the juices run absolutely clear - pink _is not_ good enough. In fact, it is necessary for the internal temperature of a hamburger pattie to reach 160 degrees F to kill all of any contaminating E. coli. 5. In day-care centers, schools, etc., any small children with diarrhea should be carefully handled, and kept separate from all well children. All diapers, and any soiled clothing should be kept separate from all well children. The day-care worker, teacher, and health-care personnel should practice strict hygeine at all times, regardless of the health of the children.