What should you know about cholera due to Vibrio cholerae O1 biovar cholerae?

Vibrio cholerae is a bacterium that can live in contaminated water or food. O1 identifies a group associated with cholera illness, while biovar cholerae is a further laboratory classification. The label describes the organism identified by testing; it does not predict how severe an individual person's illness will become.

The infection affects the intestine and may produce sudden, large-volume watery stools with or without vomiting. The dangerous feature is loss of water and salts, which can progress quickly. Transmission occurs when contaminated material is swallowed, not because the bacteria are airborne during ordinary conversation.

If a clinician suspects or confirms cholera, follow the treatment plan and start appropriate oral rehydration when the person is awake and able to drink. Use safe water, wash hands with soap, and clean areas contaminated by stool or vomit. Do not prepare food for others while ill, and follow local public-health instructions about testing and infection control.

For an overview of loose stools, see [Diarrhoea](/symptoms/diarrhoea/). [Oral Rehydration Therapy](/treatments/acute-and-urgent-care/oral-rehydration-therapy/) may replace fluid when drinking is possible; severe dehydration may need [IV Fluid Therapy](/treatments/acute-and-urgent-care/iv-fluid-therapy/).

Go for urgent assessment if watery stools are frequent, vomiting prevents drinking, urine becomes scant, or the person develops severe thirst, dizziness, fainting, weakness, confusion, or unusual sleepiness. Infants, pregnant people, older adults, and people with kidney or heart problems should be assessed early because fluid shifts may be harder to manage safely.

What did the test show, and does it change my treatment? How much oral rehydration should I take? Do household contacts need advice or monitoring? Which symptoms mean I should return immediately?