Cholera

May 18, 2017 Know Public Health Communicable Diseases, Info 0

Cholera; Introduction, Signs Symptoms, Diagnosis, Prevention, Control
Image taken from: CDC

Introduction

Cholera is acute, secretory diarrhea caused by Vibrio cholerae of the O1 and O139 serogroups. It is an important public health problem worldwide mostly at the time of outbreaks and in developing countries. Developed countries show no cases of Cholera over centuries because of the good water and sewage treatment facilities.

Cholerae is a member of the Vibrionaceae family of curved, Gram-negative rods that are found in coastal waters and estuaries. This species has been classified into more than 20 serogroups on O antigen of the lipopolysaccharide; of these, only O1 and O139 serogroups cause epidemic cholera. When the pathogen is ingested, majority of them are killed by gastric acid. The one which survive colonize the small intestine and elaborate cholera toxin, it’s the major virulence factor of V. cholerae.



Cholera can kill within hours if left untreated. Researchers have shown that each year due to cholera there are 1.3 million to 4 million cases of cholera and 21,000 to 143000 deaths worldwide. In majority of cases children are suffered from cholera. Cholera has been categorized as the one of the emerging and reemerging infections, threatening many developing countries.

Cholera occurs in both endemic and epidemic patterns. It is found endemic in many parts of Asia and Africa. Environmental factors are important in the epidemiology if the cholera. The incubation period of cholera ranges from 12 hours and 5 days.

Signs and Symptoms

  • Profuse watery diarrhoea, sometimes described as “rice-watery stools.”
  • Vomiting
  • Rapid heart rate
  • Loss of skin elasticity
  • Dry mucous membranes
  • Low blood pressure
  • Thirst
  • Muscle cramps
  • Restlessness or irritability.

These are the symptoms but the person with severe cholera can develop renal failure, severe electrolyte imbalance leading to coma. If not treated, severe dehydration can rapidly lead to shock and death in hours

Diagnosis

  • Isolation and identification of Vibrio cholerae serogroup O1 or O139 by culture of stool specimen.
  • The Crystal VC® dipstick rapid test

Prevention and Control



  • Prevention of cholera is dependent on access to safe water,basic hygiene needs, and adequate sanitation .
  • Cook food well, keep it covered, eat it hot and always peel fruits and vegetables.
  • Vaccination for adult who are 18-64 years old and travelers who are travelling to an area of active cholera transmission with cholera vaccine called Vaxchora.
  • After defecating, wash hands with soap and safe water .

Treatment

  • Rehydration therapy
  • Antibiotic treatment
  • Zinc treatment

References

  1. WHO fact sheet  
  2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3761070
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3314202
  4. https://www.cdc.gov/cholera/illness.html
  5. https://www.webmd.com/a-to-z-guides/cholera-faq#2
  6. https://www.medicalnewstoday.com/articles/189269.php
  7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC98947