Cholera is an acute secretory diarrheal illness caused by the bacterium Vibrio cholerae. It spreads through contaminated food and water. Symptoms include copious watery diarrhea that can lead to severe dehydration and death if untreated. Treatment focuses on oral rehydration and intravenous fluids to replace fluid losses. Antibiotics may also be given. Prevention relies on water treatment, sanitation, handwashing, and oral cholera vaccines.

1. Cholera
HASSAN QURESHI

2. About Myself
Born and Raised in
Jersey
Rutgers University
2007
LECOM class of 2014

3. OBJECTIVES
DEFINITION
EPIDEMIOLOGY
ETIOLOGY
RISK FACTORS
HISTORY & EXAM
TESTS
SCREENING
DIAGNOSIS
TREATMENT
PREVENTION

4. Definition
Vibrio Cholerae
 Secretory diarrheal
illness caused by gram
negative curved rods
 Oxidase positive
 Ferments Sucrose
 Grow naturally in
marine waters
 Fecal-oral
transmission

5. Pathogenesis
Vibrio Cholerae
 Vibrio Cholerae
enterotoxin activates the
stimulatory Gs protein
via ADP-ribosylation.
This stimulates secretion
of chloride ions and
water from enterocytes
into the small intestines,
and causing watery
diarrhea.

6. Epidemiology
 Major pandemics since 1817
 V. cholerae O1 biotype el tor
 Began in Asia in 1961, spread to Africa and Europe
 In 1991, the pandemic strain spread to Peru
 V. cholerae O139 Bengal emerged in 1992 in India
 History of travel (S. America, India, Asia)

7. Epidemiology
Cases have occurred in U.S. (1992)

8. Etiology
 Drinking contaminated and inadequately sterilized water or
eating undercooked seafood
 Risk Factor: antacids and achlorhydria
 Gastric acid production is reduced will allow easier entrance of the
bacteria to the small interstines
 Based on agglutination of antiserum against O1 (LPS) antigen
 O1 and non-O1 strains
 V. cholerae O1 and O139 associated with epidemics
 Produce cholera toxin
 Non-O1, non-O139 serotypes
 Cause diarrheal disease identical to classical cholera but does not
cause large outbreaks of disease.
 Due to being a nonadherent strain.

9. DIAGNOSIS

10. Risk Factors
 Ingestion of contaminated water
 Replicates in fresh and low-salt-containing water
 Drinking unsterile water and ice in developing countries
 Ingestion of comtaminated food sources
 Shelfish, clams, oysters and crabs and its products or food handlers
 High poverty
 Urban slums, refugee camps, conflict zones, naterual disasters and
prisons where sanitation facilities may not exist
 Periods of flooding
 Peope using tube-wells that become contaminated with fecal contents
from the poo-quality sanitation.
 Blood Group O at a risk of more severe disease, but
may actually be protective against initial infection.

11. Key Diagnostic Factors
 Onset begins 2-3 days after ingestion of bacteria
 Copious Watery Diarrhea
 Diarrhea >1 liter/hour is most likely cholera if sustained.
 >20 mL/kg during a 4-hour observation period
 Evidence of Volume Depletion (WHO Criteria)
 Mild (<5% volume depletion) = alert, but increased HR, dry mucous
membranes and small postural BP drop (<20 mmHg)
 Moderate (5% to 10%) = irritability, sunken eyes, dry mouth, decreased
skin turgor significant (>20 mmHg) postural BP drop.
 Severe (>10% volume depletion) = lethargy or coma, circulatory collapse
(systolic BP< 80 mmHg
 Family History of recent, severe cholera outbreak
 Family clusters due to secondary cases or due to a common source

12. Key Diagnostic Factors Continued
Greater than 20 Liters
Rice Water Stool
lost per day

13. Diagnostic Tests
 CBC  Elevated Hct / Neutrophil CT.
 Serum Electrolyes  K+ (low normal or high) and
anion gap acidosis
 ECG  Assess severtiy of volume
depletion
 Serogroup confirmation
 Antisera
 Either O1 or O139
 Darkfield Phase contrast  Large quantity of curved
microscopy of stool bacteria

14. Diagnostic Tests Continued
Vibrio Cholerae
 Microscopy:
 Small, rarely seen on
stool Gram stain
 Darkfield microscopy
can be used
 Culture:
 Next Slide

15. Question
 What media does V. Cholerae grow on?
 A. Mannitol salt agar
 B. Eosin methylene blue
 C. Thiosulfate citrate bile salts sucrose
 D. Buffered charcoal yeast extract agar
 E. Don’t care, hurry up I want to leave.

16. C.
Thiosulfate
citrate bile
salts sucrose
(TCBS) agar

17. World Health Organization Diagnosis Criteria
[WHO: Standard clinical case definition]
 WHO Standard case definition:
A case of cholera suspected when:
 An area where the disease is not known to be present, a patient aged
5 years or more develops severe dehydration or dies from acute
watery diarrhoea;
 In an area where there is a cholera epidemic, a patient aged 5 years
or more develops acute watery diarrhoea, with or without vomiting.
 A case of cholera is confirmed when Vibrio cholerae O1 or O139 is
isolated from any patient with diarrhoea.

18. TREATMENT
HYDRATION
HYDRATION
HYDRATION
!!!!!!!!!!!!!!!

19. Treatment
 No need for a a formal diagnosis of cholera to initiate treatment
 Urgent rehydration is the most important feature of treatment.
 IV rehydration is usually started for severely volume-depleted
patients, but oral replacement solution (ORS) is the mainstay of
therapy for mild-to-moderate disease and should be added to IV
therapy as soon as is clinically possible.
 Antibiotics (based on local resistances) reduce both the severity and
length of disease and should be used where possible
 Vitamin and micronutrient supplements in specific cases.
 Antisecretory agents have NOT been shown to be useful

20. The standard
World Health
Organization
Oral
Rehydration
Salts (ORS)
comes
prepacked and
contains:
Na+ 75, K+ 20, Cl- 65, citrate 10,
and glucose 75, with an osmolality
of 245 mosmol/L (all in mmol/L)

21. Treatment of Severe Volume Depleted
 Precisely calculating volume depletion is difficult. The
equations provided in WHO document may be used in
balance with clinical judgment. [WHO/UNICEF: Clinical
mgmt of acute diarrhea]
 Secretory diarrhea is high in Sodium, Potassium and
Bicarbonate therefore Ringer lactate should be used.
 With the loss of Bicarbonate and Potassium in the stool,
cholera patients have a profound metabolic acidosis and
total body K+ depletion.
 K+ should be replaced through inclusion of K+ in the IV or oral
fluids regardless of initial K+ level.

22. Treatment of Moderate - Mild Volume Depleted
 Oral Rehydration is usually preferred as this avoids
the complications of IV fluids
 Aggressive catch-up rehydration for 2-4 hours,
followed by maintenance fluids until diarrhea stops,
which takes 2 to 5 days later.

23. A SLIDE WITH NO USEFUL
INFORMATION AT ALL
JUST FILLING IN THE GAP BETWEEN THE LAST SLIDE
AND THE NEXT ONE (WHICH WILL BE ALONG IN JUST A
MOMENT)
NO NEED TO WRITE THIS DOWN, UNLESS YOU FEEL
COMPELLED TO DO SO
NOTHING ON THIS SLIDE IS EXAMINABLE
IN FACT I’M NOT REALLY SURE WHY I BOTHERED WITH
IT

24. Cholera Cot
Death can occurs within hours if untreated
60% mortality rate in untreated patients and <1% in treated
 The use of the cholera
Cot enables health care
providers to measure
the enteric loss and
replace losses with an
equal volume of oral or
IV fluids.

25. PREVENTION

26. Prevention
 Water treatment and sanitation with chlorination of
municipal water supplies.
 Boiling or filtration of water locally
 Health education
 Attention to careful handwashing with soap and water
 Disinfection of the dead and their belongings with simple
burial procedures
 2 oral vaccines available
 Composed of Killed, whole-cell bateria
 Contains the B-toxin subunit

27. Questions

28. The Painted Veil (2006)

29. References
 https://online.epocrates.com/noFrame/showPage.do?
method=diseases&MonographId=451&ActiveSectionId
=11
 Google Images
 http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH000
1348/
 http://www.nathnac.org/pro/factsheets/documents/C
holerarevisedAug07.pdf
 http://www.uptodate.com/contents/minor-vibrio-and-
vibrio-like-species-associated-with-human-
disease?source=search_result&search=cholera&selecte
dTitle=3~57#H631646153