Most persons infected with cholera will have very mild illness or have no symptoms and won’t feel ill at all. Mild cholera presents as a diarrhoeal illness and isn’t easily distinguished from other common causes of diarrhoea.
The incubation period (the period from when the person ingests cholera contaminated water/food to when they first become ill) ranges from a few hours to 5 days (usually 2-3 days). Even if a person has no symptoms bacteria can remain in their stools up to 14 days meaning they can still potentially infect other people.
Common symptoms are: Acute watery diarrhoea (usually painless), muscle cramps or spasms, nausea and vomiting. Fever is uncommon but can occur mostly in children. These symptoms can begin within hours of being infected but can take up to 5 days to develop after ingesting contaminated food or water.
In its severe form, cholera typically presents as follows:
• sudden onset of illness
• diarrhoea becomes severe, painless and watery, with flecks of mucus in the stool (looks like "rice water" stools)
• vomiting may occur, usually early in the illness
• most persons don’t have fever, although children may develop a fever
• dehydration occurs rapidly and if untreated can be fatal
Diagnosis is confirmed by stool sample testing by the laboratory. People do not have to wait for results to start treatment, especially during an outbreak. Diarrhoea with dehydration in adults should have a high suspicion of cholera!