Key points
- In 2025 cholera caused 451,499 cases and 7,870 deaths in 47 countries — the highest annual death toll since 1999 (WHO cholera fact sheet, 29 September 2026).
- Cholera is a disease of unsafe water and poor sanitation. WHO calls it an indicator of inequity and lack of social and economic development.
- Conflict and displacement drive outbreaks: in Yemen, cases tripled in three weeks as conflict displaced more than 200,000 people.
- Prevention is safe water, handwashing with soap, freshly cooked food and safe sanitation — plus oral cholera vaccine in outbreak settings.
Direct answer: Cholera keeps coming back because it is a disease of unsafe water and poor sanitation — and because conflict, displacement and climate events keep breaking the water and sanitation systems that hold it back. In 2025 it caused 451,499 cases and 7,870 deaths in 47 countries, the highest annual death toll since 1999 (WHO cholera fact sheet, 29 September 2026). Prevention is safe water, handwashing, freshly cooked food, safe sanitation, and oral cholera vaccine in outbreak settings.
What cholera is
Cholera is an acute diarrhoeal infection caused by the bacterium Vibrio cholerae, swallowed in contaminated water or food. Most people who are infected have no symptoms or mild ones, but in severe cases the watery diarrhoea can dehydrate a person within hours. It is the seventh cholera pandemic, running since 1961, and it remains a global threat — not a disease of the past. The 2025 toll of 451,499 cases and 7,870 deaths in 47 countries was the highest annual death toll since 1999, according to WHO’s cholera fact sheet of 29 September 2026.
The 2026 picture so far
Between 1 January and 30 August 2026, WHO recorded 275,284 cholera and acute watery diarrhoea cases and 2,601 deaths in 28 countries — 43% fewer cases than the same period in 2025. That fall must not be read as cholera declining: WHO explicitly warns that reporting delays and different case definitions mean the lower count is no proof transmission has fallen. The worst-affected countries in 2025 were Nigeria, Angola, Bangladesh, the Democratic Republic of the Congo, South Sudan, Sudan and Yemen, together accounting for about 90% of cases and deaths. In the DRC alone there were about 60,000 cases and 1,800 deaths from the start of 2026 (WHO Director-General, early November 2026).
Why it keeps coming back
WHO’s fact sheet names the drivers plainly: cholera outbreaks “may be due to conflict, population displacement, climate events like cyclones, floods or drought, and lack of investment in maintaining and improving WASH services”. Yemen shows the mechanism: escalating conflict from 6 August 2026 displaced more than 200,000 people across 10 governorates into overcrowded camps with unsafe water, and weekly cases tripled from 217 to 647 in three weeks to 3 October 2026 — 8,034 suspected cases and 27 deaths in 2026 (WHO EMRO, 13 October 2026). In Sudan, WHO attributes the severity of the outbreak to the war, 13.4 million displaced people, overwhelmed facilities and a supply blockade. In the DRC, cholera concentrates in North and South Kivu, areas frequently experiencing conflict between armed groups. And cholera “indicates inequity and lack of social and economic development” — it strikes hardest where water and sanitation are weakest.
There is also a supply constraint. A global shortage of oral cholera vaccine since October 2022 meant only single-dose regimens could be used; production has more than doubled since (about 30 million doses in 2022 to about 80 million in 2025), but demand still pressures supply, and preventive vaccination only resumed in 2026 (20 million doses allocated in February 2026).
How cholera is prevented
The prevention measures are the same ones the WHO fact sheet lists, and they are all about water, food and hands: use safe (treated or boiled) water for drinking and cooking; wash hands with soap, especially after using the toilet and before handling food; eat freshly cooked food and avoid food that has been standing; use safe sanitation and keep human waste away from water sources. Oral cholera vaccine can help in outbreak settings — ask a health professional or follow the local campaign. This page does not advise any individual; for the water, sanitation and hygiene systems behind prevention, see the WASH guide and the WASH tool on this site.
Frequently asked questions
Is cholera declining?
Not as a headline. Reported cases in January to August 2026 were lower than the same period in 2025, but WHO warns reporting delays mean this is no proof transmission has fallen.
How do people catch cholera?
By swallowing water or food contaminated with Vibrio cholerae, usually where drinking water and sanitation are unsafe. It is not caught through casual everyday contact.
Is there a cholera vaccine?
Yes, an oral cholera vaccine is used in outbreak settings and campaigns. Ask a health professional or follow the local campaign; this page does not advise individuals.