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Diseases / Cholera


What is it?: 

Cholera is a rapidly-dehydrating diarrhoeal disease, caused by toxigenic serogroups of the bacterium Vibrio cholerae; the disease is closely associated with poverty, poor sanitation and lack of clean drinking water.1

Approximately 1.3 billion people are at risk of cholera in endemic countries. An estimated 2.86 million cholera cases occur annually in endemic countries. Among these cases, there are an estimated 95 000 deaths. 1

About half of the cholera cases and deaths are estimated to occur in children ≤5 years of age, but any age group may be affected.1

Clinical features: 

Most patients do not have symptoms or only have mild diarrhoea while some develop severe watery diarrhoea with rice-water like stool and vomiting. Without prompt treatment, these patients may die from severe dehydration.2

Mode of transmission: 

Cholera is usually contracted through consumption of food or water contaminated with Vibrio cholerae. Human-to-human transmission rarely happens.2

Incubation period: 

Ranges from a few hours to 5 days, usually 2 - 3 days.2


Maintain good personal hygiene2

  • Perform hand hygiene frequently, wash hands thoroughly with liquid soap and water before handling food or eating, and after using toilet, or handling faecal matter.
  • Exclude infected persons and asymptomatic carriers from handling food and from providing care to children, elderly and immunocompromised people.
  • Refrain from work or school, and seek medical advice if suffering from gastrointestinal symptoms such as diarrhoea.

Food hygiene2

  • Drink only boiled water from the mains or bottled drinks from reliable sources.
  • Avoid drinks with ice of unknown origin.
  • Purchase fresh food from hygienic and reliable sources. Do not patronise illegal hawkers.
  • Susceptible populations and those who wish to reduce the risk of foodborne illnesses should avoid consuming raw and undercooked foods.

Environmental hygiene2

  • Maintain proper sanitary facilities and drainage system.
  • Cleanse and disinfect toilets used by infected person and the soiled areas.


  • Oral cholera vaccine is rarely recommended except for those at high risk e.g. aid workers. It is not officially required as a condition of entry of any country. Please visit the website of Travel Health Service of the Department of Health for more details.

The mainstay of treatment is timely and adequate rehydration. For mild dehydration, patients may take oral rehydration solution. Severe dehydration cases usually require intravenous rehydration to replenish fluid and electrolyte loss. Antibiotics may also be used if needed.2


  1. World Health Organization. Weekly epidemiological record. Cholera vaccines: WHO position paper - August 2017. 2017;34(92):477-500.
  2. Centre for Health Protection. Communicable diseases – Cholera. 5 Jul 2019. [ONLINE] Accessed 15 Mar 2021.