1. Cholera is an infection in the small intestine caused bythe
bacterium Vibrio cholerae. The main symptoms areprofuse, watery
diarrhea and vomiting. Transmissionoccurs primarily by drinking
water or eating food that hasbeen contaminated by the feces of an
infected person,including one with no apparent symptoms.
2. The Bacteria that causes Cholera
3. Acute infectious disease is often fatal characterized by
severe vomiting, diarrhoea, and collapse
4. Caused By: Vibrio cholerae Indirect transmission Vehicle
borne Reaches water through: Vomiting Diarrhoea Carriers active or
passive Produces toxins in sml intestines that cause severe
diarrhoea and dehydration
5. Through: Contaminated water Contaminated food Eating with
unwashed hands Also house flies and otherinsects
6. The primary symptoms of cholera are profuse, painless
diarrheaand vomiting of clear fluid. These symptoms usually start
suddenly,one to five days after ingestion of the bacteria. The
diarrhea isfrequently described as "rice water" in nature and may
have a fishyodor.An untreated person with cholera may produce 10 to
20 liters (3 to5 US gal) of diarrhea a day with fatal results. For
every symptomaticperson, 3 to 100 people get the infection but
remain asymptomatic.Cholera has been nicknamed the "blue death" due
to a patientsskin turning a bluish-gray hue from extreme loss of
fluids.
7. If the severe diarrhea is not treated with intravenous
rehydration, itcan result in life-threatening dehydration and
electrolyteimbalances.The typical symptoms of dehydration include
low bloodpressure, poor skin turgor (wrinkled hands), sunken eyes,
and arapid pulse.A person with severedehydration due to cholera
-note the sunken eyes anddecreased skin turgor whichproduces
wrinkled hands
8. Hostdrinks water Bacteria moves through the stomach Reach
the intestine & produce flagella Propel through mucus of the
sm.intestine Produce toxin causing diarrhea Feces carry new
bacteria into drinkingwater
9. When consumed, most bacteria do not survive the acidic
conditions ofthe human stomach. The few surviving bacteria conserve
their energyand stored nutrients during the passage through the
stomach byshutting down much protein production.When the surviving
bacteria exit the stomach and reach the smallintestine, they need
to propel themselves through the thick mucus thatlines the small
intestine to get to the intestinal walls where they canthrive. V.
cholerae bacteria start up production of the hollow
cylindricalprotein flagellin to make flagella, the cork-screw
helical fibers theyrotate to propel themselves through the mucus of
the small intestine.
10. Once the cholera bacteria reach the intestinal wall they no
longerneed the flagella to move. The bacteria stop producing the
proteinflagellin to conserve energy and nutrients by changing the
mix ofproteins which they express in response to the changed
chemicalsurroundings. On reaching the intestinal wall, V. cholerae
startproducing the toxic proteins that give the infected person a
waterydiarrhea.This carries the multiplying new generations of V.
cholerae bacteriaout into the drinking water of the next host if
proper sanitationmeasures are not in place.Advanced Mechanism
Structure Next
11. Stage 1Stage 3 Vomiting Start to recover Muscle cramps Mild
to severe diarrhoea Sudden onset and watery, Shock and
dehydrationpainless diarrhea Loss of important minerals Stool has a
characteristic rice and electrolyteswater appearance (gray,slightly
cloudy with bits of Intense thirstmucus, and a slightly sweaty
Reduced urinationodor) Muscle cramps/weaknessStage 2 Dehydration,
Thirst and Shock Cold Skin, sunken Eyes, weakpulse and feint
high-pitchedvoice Reduced urine Muscle cramps and
Muscleweakness
12. OralRehydration Therapy (ORT) Solution of salts and sugars,
taken by the mouth Also homemade solutions (water, sugar,
tablesalt, baking soda, and fruit) Sometimes intravenous
13. Tetracycline Shortens the course of the disease Weaken the
symptoms.
14. Squatter camps Bad hygiene Unsafe preparation of food
Drinking contaminated water To bathe / swim in contaminated
water
15. Immunization Boiling water, covering food Education
Personal and domestic hygiene Prevention of contamination of water
supplies Improvement of sewage systems Access to health care
16. Although cholera may be life-threatening, prevention ofthe
disease is normally straightforward if propersanitation practices
are followed. In developed countries,due to nearly universal
advanced water treatment andsanitation practices, cholera is no
longer a major healththreat.