Stage of Evacuation
The onset is abrupt with profuse, painless, watery diarrhea followed by vomiting. The patient may pass as many as 40 stools in a day. The stools may have a rice water appearance.

Stage of Collapse
The patient soon passes into a stage of collapse due to dehydration. Death may occur due to it. The classical form of severe cholera occurs in only 5 to 10% of cases. In the rest, the disease tends to be mild, characterized by diarrhea with or without vomiting or marked dehydration. As a rule, mild cases recover in about one to three days.

Laboratory Diagnosis of Cholera
The organisms can also be isolated from contaminated water or food. Laboratory methods of diagnosis are required to confirm the diagnosis:

Collection of Stools
A fresh sample should be collected before the person is treated with antibiotics.

Direct Examination
It may be possible to diagnose about 80% of the cases within a few minutes.