Cholera

What is Cholera?

Cholera is a disease of the gastro-intestinal tract and is caused by a bacterium known as Vibrio cholerae. There are multiple types and strains of these bacteria. Outbreaks of cholera are common in many tropical countries around the world. Serious epidemics can occur anywhere in the world where water supplies, sanitation, food safety and hygiene are inadequate. Overpopulated communities and refugee camps are particularly high risk settings due to poor sanitation and unsafe drinking water supplies.

Cholera can be a dangerous and sometimes fatal disease because it may cause severe diarrhoea and rapid dehydration resulting in hypotension (low blood pressure), shock, and death, sometimes within hours.

How do you get Cholera?

Cholera is spread by eating food or drinking water contaminated by the feces or vomit of infected persons. Contaminated municipal water supplies and unsafe water storage can lead to large scale outbreaks. The organism can remain alive in water for considerable periods of time. Sources of cholera infection include beverages and ice prepared with contaminated water, fruits and vegetables washed with contaminated water, as well as raw or undercooked seafood. Infected food handlers who do not practice good personal hygiene can introduce cholera into prepared foods.  For safe eating and drinking, wash your hands often.

Susceptibility and Resistance

Generally, everyone is susceptible in the absence of any previous exposure. After acute infection and illness, some immunity does develop but not against all strains of the bacterium.

Incubation Period

The incubation period for Cholera is 1-5 days.

What are the Symptoms?

Infection with the cholera bacteria results in a very sudden onset of profuse, painless, watery diarrhoea with nausea and vomiting. If not treated rapidly, dehydration can occur with collapse of the circulation, resulting in death, sometimes in just a few hours. There are many variations in the illness due to the different strains of cholera bacteria. The infection can range from a very mild, almost unapparent illness to a severe life-threatening disease. With proper rapid treatment, death occurs in less than 1 percent of the cases, but in untreated severe cases, death may occur in up to 50 percent of the cases.

Preventative Measures

Avoid improperly prepared food and water that is not bottled or boiled. If you are exposed to a person with cholera where there is an increased risk of transmission, e.g., living in the same household, you should seek medical advice to obtain an appropriate antibiotic to prevent the illness from developing.

An oral cholera vaccine is currently available but only provides limited protection for relatively short periods of time.  The vaccine is given in two doses at least one week apart and both doses should be finished at least one week before travelling to an area where the traveller might come in contact with cholera.

Treatment

Treatment consists of three measures:

  1. Aggressive replacement of lost fluid by oral or intravenous means;
  2. Administration of an effective antibiotic (e.g., tetracycline or one of several other readily available antibiotics) to reduce the volume of loss of fluids and the duration of the diarrhoea; and
  3. Treatment of any complications that may result from the aggressive replacement of lost fluid.

Medications

Vaccinations

Where Does It Commonly Occur?

Cholera is commonly found in many tropical countries around the world.