A community health worker with a megaphone raises awareness about cholera in Bujumbura’s Buterere market. She explains the importance of handwashing before and after meals, and of washing and cooking fruit and vegetables to kill the bacteria. She also explains how to recognise initial symptoms of cholera, and what to do if they suspect they or a family member has caught the disease. © Evrard Ngendakumana/MSF


Cholera is a deadly but treatable disease that affects millions worldwide. It often breaks out when there is overcrowding and inadequate access to clean water, rubbish collection and clean toilets. 

It causes profuse diarrhea and vomiting which can lead to death by intense dehydration, sometimes within a matter of hours. Cholera is a serious risk in the aftermath of emergencies, like the cyclones that struck Mozambique in 2019, but can strike anywhere. The situation can be especially problematic in rainy seasons when houses and latrines flood and contaminated water collects in stagnant pools. 

In 2018, Doctors Without Borders/Médecins Sans Frontières (MSF) treated 63,722 people for cholera across the globe.

What causes cholera?

Cholera is caused by an infection of the intestine with the bacterium Vibrio cholerae. The bacterium causes the cells lining the intestine to produce large amounts of fluid, leading to profuse diarrhea and vomiting.

The infection spreads when someone ingests food or water contaminated with the feces or vomit of someone carrying the disease.

Contaminated food or water supplies can cause massive outbreaks in a short period of time, particularly in overcrowded areas such as slums or refugee camps.

Symptoms of cholera

Typically, symptoms of cholera appear within two to three days of infection. However, it can take anywhere from a few hours to five days or longer for symptoms to appear.

A cholera infection can be mild or without symptoms but can also be severe, resulting in profuse watery diarrhea, vomiting and leg cramps.


Diagnosing cholera

Cholera can be diagnosed by examining stool samples or rectal swabs but, due to the fast-acting nature of the disease, there is often little time to do so.

In epidemic situations, a diagnosis is often made by taking a patient history and conducting a brief examination, with treatment given before there is time for a laboratory to confirm the diagnosis.

Treating cholera

Cholera can be treated simply and successfully by immediately replacing the fluids and salts lost through vomiting and diarrhea – with prompt rehydration, less than one per cent of cholera patients die.

Cholera victims are always treated with oral rehydration solutions – prepackaged mixtures of sugars and salts that are mixed with water and drunk in large amounts. Severe cases will need these fluids to be replaced intravenously via a drip, and antibiotics are sometimes administered.

The patient rapidly loses body fluids, leading to dehydration and shock. Without treatment, they may die within hours.