Cholera

Most people infected with V. cholerae will NOT become unwell. Of those who do develop symptoms, most will have mild or moderate diarrhoea with little fever. However, some people will develop profuse watery diarrhoea with severe dehydration, which can lead to death within hours if not treated.

Dehydration due to cholera can be easily treated in most cases with oral rehydration solution, a mixture of sugar and salts in water. Intravenous fluids, and sometimes antibiotics, may be required for people with severe disease.

Cholera is usually spread by food or water that has been contaminated by human faeces. People can also become infected if they eat raw seafood taken from contaminated sea waters.

Direct person-to-person spread of cholera is uncommon.

Cholera can spread rapidly in areas where sewage and drinking water supplies are not adequately treated. It is very rare in countries that have adequate sanitation and safe water supplies. The risk of a cholera outbreak anywhere in Australia is extremely low.

The time between being exposed to V. cholerae and becoming unwell is short, usually between 2 hours and 5 days.

Severely dehydrated patients may require intravenous fluids and antibiotics.

While cholera is a very rare disease in Australia, the following good hygiene measures should help to prevent gastrointestinal illnesses in general.

• Wash hands with soap and running water, and dry them thoroughly:
• after using the toilet or changing nappies
• before preparing, cooking and eating food
• after cleaning or contact with soiled items.
• Avoid sharing linen and towels with an ill person.
• Wash these items and any clothing from the person separately in hot water.
• Clean soiled surfaces with warm water and a detergent.
• Wash all shellfish, fruits and vegetables in clean treated water.
• Store cooked foods and raw foods separately.
• Use different chopping boards and utensils for preparation of raw and cooked foods (or wash them well in warm soapy water before reusing).
• Do not drink untreated water from wells or creeks.
• People with diarrhoea and/or vomiting should not handle or prepare food until they have been well for at least 24 hours; food handlers must not work until they have been well for at least 48hrs.

Additional precautions when travelling

By taking a few basic precautions, travellers can protect themselves against cholera and most other food and water-borne diseases, even in areas with no clean water and poor sanitation.

Above all, travellers should be very careful with food and water, including ice. Remember this simple rule: Boil it, cook it, peel it, or forget it.

• Drink only water that has been boiled or disinfected with chlorine, iodine or other suitable products.  Products for disinfecting water are generally available in pharmacies.
• Other safer drink choices include hot tea or coffee; water, sodas, sports drinks from a sealed can or bottle (carbonated is safer); and fruit juices, wine or beer from a sealed bottle, can or package.
• Avoid ice, unless you are sure that it is made from safe water.
• Eat food that has been thoroughly cooked and is still hot when served.
• Avoid raw or undercooked foods. The exceptions are fruits and vegetables that you have washed in clean water, or peeled yourself.
• Boil unpasteurised milk before drinking it.

Vaccination

An oral cholera vaccine is available.  Most travellers do not require vaccination for cholera as they have a very low risk of illness.

Oral vaccine is recommended:

• for travellers at high risk of exposure such as humanitarian relief workers in disaster areas and refugee camps
• for travellers vulnerable to severe diarrhoea, such as those with impaired immunity or with inflammatory bowel disease. (Consult your doctor for more information.)

13 HEALTH (call 13 43 25 84)

Immunisation Australia (call 1800 671 811)

For further information please contact your local doctor or nearest public health unit or call 13 HEALTH (13 43 25 84) 24 hours a day 7 days a week for the cost of a local call.

References

Heymann D (ed), 2015.  Control of Communicable Diseases Manual, 20th edition.  Washington, DC: American Public Health Association.

Cholera factsheet, World Health Organization

National Health and Medical Research Council, 2013. The Australian Immunisation Handbook, 10th edition, 4.1 Cholera. Australian Government Department of Health and Ageing: Canberra.