Cholera

Cholera is an acute diarrheal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae, specifically affecting the small intestine. Only two serogroups, O1 and O139, are known to cause cholera outbreaks, with V. cholerae O1 responsible for all recent epidemics. The disease serves as an indicator of inequity and lack of social and economic development in affected populations.

Cholera presents with a spectrum of symptoms ranging from asymptomatic infection to severe, rapidly fatal disease. The classic manifestation is profuse, watery diarrhea often described as 'rice water' in appearance with a characteristic fishy odor, which may be accompanied by vomiting of clear fluid and muscle cramps. An untreated individual may produce 10 to 20 liters of diarrhea per day, leading within hours to severe dehydration, electrolyte imbalance, sunken eyes, cyanotic skin, and decreased skin elasticity. Most infected persons develop mild or moderate symptoms, while a minority progress to life-threatening dehydration that can kill within hours without treatment. The incubation period ranges from 12 hours to 5 days following exposure.

Cholera remains endemic in multiple regions and periodically causes outbreaks in areas with compromised water and sanitation infrastructure. Global annual burden is estimated at 1.3 to 4.0 million cases resulting in 21,000 to 143,000 deaths, though reported figures to WHO in 2023 showed 535,321 cases and 4,007 deaths from 45 countries, suggesting significant underreporting due to surveillance limitations. The disease is strongly associated with limited access to safe water, inadequate sanitation facilities, and poor hygiene practices, with outbreaks frequently triggered by conflict, population displacement, climate events such as floods or drought, and insufficient investment in water, sanitation, and hygiene infrastructure. The current seventh pandemic began in South Asia in 1961 and continues to affect populations worldwide.

Cholera is transmitted primarily through the fecal-oral route via consumption of food or water contaminated with V. cholerae from infected individuals. Poor sanitation is the underlying driver of transmission, with most cases in developing countries linked to contaminated water while foodborne transmission predominates in developed settings. Undercooked shellfish harvested from contaminated waters represents a common vehicle, as V. cholerae accumulates in planktonic crustaceans that filter-feeding shellfish consume. Humans are the only known reservoir for the pathogenic serogroups, and infected persons can shed bacteria in their feces for 1 to 10 days even when asymptomatic.

Children aged two to four years experience the highest infection rates among all age groups, reflecting both exposure patterns and developing immunity. Individuals with blood type O demonstrate increased susceptibility to severe disease compared to other blood types. Persons with compromised immunity, including those with AIDS and malnourished children, face elevated risk of developing severe cholera if infected. Additionally, individuals with reduced gastric acidity require a lower infectious dose to develop disease, making those using proton pump inhibitors more vulnerable. Populations lacking access to clean water, adequate sanitation, and hygiene services bear the greatest burden of disease.

Prevention and control of cholera require a comprehensive approach combining improved water, sanitation, and hygiene infrastructure with vaccination and community engagement. Access to safe water and basic sanitation facilities is fundamental to preventing transmission, while oral cholera vaccines provide reasonable protection for approximately six months. Health education emphasizing handwashing with soap after defecation and before food handling, along with safe food preparation and storage practices, forms an essential component of prevention strategies. Strengthening surveillance systems enables early outbreak detection and guides rapid public health response.

Cholera surveillance requires strong epidemiological and laboratory capacity to swiftly detect cases, confirm outbreaks through stool testing or rapid diagnostic methods, and monitor transmission patterns. The discrepancy between estimated and reported case numbers reflects significant surveillance gaps in many endemic settings, suggesting that reported figures represent only a fraction of the true global burden. Countries need robust surveillance systems not only to identify outbreaks but also to guide resource allocation, evaluate control measures, and track the effectiveness of vaccination campaigns in at-risk populations.

1. 1 WHO Health Topics. Cholera.
2. 2 WHO Fact Sheet. Cholera.
3. 3 WHO Q&A. News.
4. 4 Wikidata. cholera.
5. 5 Wikipedia. Cholera - Wikipedia.

ICD-10

A00

ICD-11

1A00

Total cases

592

Total deaths

2

Peak month

2010-08

Coverage

4 reporting countries · 2000-01-01 → 2026-05-09