Escherichia coli

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Escherichia coli

• Genus Enterobacteriaceae
• Species Escherichia coli

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• Morphology
• Gram Negative Rod
• Grows as fermenting colonies with some beta
  hemolysis upon initial isolation
• Motile
• Non-pigmented

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Physical Requirements

• Temperature
• Mesophile
• 10C, 37C, 45C
• pH
• Prefer Neutral Environment
• Oxygen
• Facultative Anaerobe

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Media Glucose Fermentor
Oxidase (-) Nitrate Reducer
Lysine () Citrate (-) Indol
() Acetate () Lactose
()
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Source

• Reservoir
• Cattle, Humans, Soil, Water
• Normal Flora
• Most predominant organism of the Large
  Intestine
• Ordinarily Non-pathogenic, but can be
  opportunistic

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Virulence Factor

• Flagella
• Fimbriae (Pili) - important for coloniaztion of
  host tissue
• Exotoxins

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Major Diseases Caused
Clinical Syndromes85 of urinary tract
infections50 of primary nosocomial pneumonia in
some hospitalsMajor cause of neonatal meningitis
with up to 80 mortalityGastroenteritis (see
above and Summary Table below for specific
syndromes and virulence factors associated with
specific strains) Wound infectionsPeritonitis
sepsis
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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.
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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.)
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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 in-between. 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.