Acute Watery Diarrhoea (AWD)

Acute watery diarrhoea is an illness characterized by three or more loose or watery (non-bloody) stools within a 24-hour period.

Suspected Cholera Case

In areas where a cholera outbreak has not yet been declared, any person 2 years of age or older presenting with acute watery diarrhoea and severe dehydration or dying from acute watery diarrhoea.

In areas where a cholera outbreak has been declared, any person presenting with or dying from acute watery diarrhoea.

Confirmed Cholera Case

A suspected case with V. cholerae O1 or O139 confirmed by culture or polymerase chain reaction (PCR). In countries where cholera was never known to be present, or has been eliminated, the V. cholerae O1 or O139 strain is demonstrated to be toxigenic.

Cholera Alert

A cholera alert (suspected cholera outbreak) is defined by the detection of at least one of the following:

a) two or more people aged 2 years or older with acute watery diarrhoea and severe dehydration, or dying from acute watery diarrhoea, from the same area within 1 week of one another;

b) one death from severe acute watery diarrhoea in a person aged 5 years or older;

c) one case of acute watery diarrhoea testing positive for cholera by rapid diagnostic test (RDT) in an area (including areas at risk for extension from a current outbreak) that has not yet detected a confirmed case of cholera.

Cholera Outbreak

A cholera outbreak is defined by the occurrence of at least one confirmed case of cholera and evidence of local transmission.

In areas with sustained (year-round) transmission, a cholera outbreak is defined as an unexpected increase (in magnitude or timing) of suspected cases, over 2 consecutive weeks, of which some are laboratory confirmed.

Cholera-Endemic Area

An area where confirmed cholera cases, resulting from local transmission, have been detected in the last 3 years. An area can be defined as any subnational administrative unit including state, district or smaller localities.

Any country that contains one or more subnational administrative units that are endemic, as defined above, is considered a cholera-endemic country.

Cholera Hotspot

A geographically limited area (such as a city, administrative level 2 or health district catchment area) where environmental, cultural and/or socioeconomic conditions facilitate the transmission of the disease and where cholera persists or reappears regularly. Hotspots play a central role in the spread of the disease to other areas.