What is cholera?
Cholera is an infection of the bowel caused by a type of bacteria known as Vibrio cholerae. Cholera is extremely rare in Australia and other developed nations, but is still fairly common in certain parts of the world, such as Asia, Africa, and South and Central America.
How do you catch it?
You can become infected if your food or drink is contaminated with cholera bacteria. The bacteria usually come from faeces or vomit from a person infected with cholera. Cholera bacteria may also live in coastal waters and brackish rivers and undercooked or raw shellfish and other seafood can be a source of infection. Cholera can spread quickly in areas that do not have a clean water supply and adequate sewage treatment systems.
Many people who become infected do not have any symptoms at all, and more than 90 per cent of people who do experience symptoms have only a mild-to-moderate form of the disease.
The main symptom is watery diarrhoea, which usually comes on suddenly. Because people with cholera can lose a lot of their body water through diarrhoea, they can become dehydrated. Dehydration can cause you to feel very thirsty, tired and light-headed.
About one in 20 people who are infected have a severe form of the disease. People with severe disease have large amounts of watery diarrhoea, accompanied by other symptoms including vomiting, abdominal pain and leg cramps.They lose fluids very quickly, resulting in severe dehydration and shock. Without treatment, people with severe disease can die within hours.
The main treatment is to replenish the fluid and salts that you have lost as a result of the diarrhoea. A special pre-packaged salt and sugar mixture, called oral rehydration salts (ORS) which you combine with water and drink, can be used to treat dehydration. This oral rehydration solution, developed by the World Health Organization, is used to treat diarrhoea all over the world. Similar oral rehydration mixtures (for example, Gastrolyte or Hydralyte) are available from pharmacies. People with severe dehydration may need to be given additional fluids through a drip.
If you have a severe case of cholera you may also need antibiotics, which can reduce the volume of diarrhoea and shorten the duration of symptoms.
If you are travelling in a cholera-affected country, it’s important to take certain steps to avoid infection.
- Always remember to drink boiled water or water that you have treated with chlorine or iodine.
- Carbonated, bottled drinks are also usually safe, but be careful not to add ice to your drinks.
- Eat foods that have been thoroughly cooked and are still hot.
- Always peel fruit and vegetables before you eat them.
- You should also avoid eating high-risk foods such as raw or undercooked seafood or meat.
- Be careful to always wash your hands properly before preparing food and eating. But generally wash your hands often with soap and water or alcohol-based hand cleaner.
The risk of getting cholera is very low if you follow these precautions. It’s also a good idea to take sachets of oral rehydration mixture with you when visiting cholera-affected countries, just in case of infection.
An oral cholera vaccine is available for people who are planning an overseas trip to an area where a cholera infection may occur, such as Africa. Adults require 2 doses. Vaccination is generally only recommended for people at high risk, such as emergency relief and health workers. People with pre-existing conditions that would be exacerbated by cholera, such as inflammatory bowel disease, may also be advised to get vaccinated.
You should still follow the food hygiene measures, because the vaccine doesn’t give complete protection and protection only lasts a relatively short time.
Ask your doctor whether you should be vaccinated before going overseas. No countries require proof that you have been vaccinated against cholera as a condition for entry.
Last Reviewed: 14/02/2013
Your Doctor. Dr Michael Jones, Medical Editor.
1. World Health Organization. Chapter 6: Vaccine preventable diseases and vaccines. Cholera. International Travel and Health 2012. http://www.who.int/ith/chapters/ith2012en_chap6.pdf (accessed Feb 2013).
2. CDC. Cholera. Last updated 24 Feb 2011. http://www.cdc.gov/cholera/general/ (accessed Feb 2013).
3. eMIMS March 2013. Dukoral Prescribing Information. (accessed Feb 2013).