Cholera is an acute intestinal infection that heavily affects populations in developing countries.
Every year, the disease kills an estimated 100,000-120,000 people and 3–5 million others are infected, according to the World Health organisation.
The disease, which can kill within hours if left untreated, is caused by ingestion of food or water contaminated with the bacterium vibrio cholera.
It is waterborne and spreads quickly in areas where sanitation is poor and access to clean drinking water is lacking.
Victims suffer a copious, painless, watery diarrhoea that leads to severe dehydration. Vomiting also occurs in most patients.
Easy to cure
The disease is easy to cure. Up to 80 per cent of cases can be successfully treated with oral rehydration salts.
"Individuals can boil water, take a litre of it and mix it with a teaspoon of salt and eight teaspoons of sugar and thereby create oral rehydration therapy," Doctor Rishi Manchanda, a specialist in public health, told Al Jazeera.
Very severely dehydrated patients also require administration of intravenous fluids and antibiotics.
The source of the contamination is typically other cholera patients when their faeces gets into waterways, groundwater or drinking water supplies.
Any infected water and any foods washed in the water can cause an infection. Cholera is rarely spread directly from person to person.
Crowded camps for internally displaced people or refugees are especially at risk of cholera outbreaks if minimum requirements of clean water and sanitation are not met.
For example, in the aftermath of the Rwanda crisis in 1994, 23,800 people died in cholera within one month in the refugee camps in Goma in the Democratic Republic of Congo.
Cholera likely has its origins on the Indian subcontinent. During the 19th century, the disease spread across the world. Six subsequent pandemics killed millions of people across all continents.
There are oral cholera vaccines available on the market, including Dukoral which is WHO prequalified and licensed in more than 60 countries.