3.2.1 Standard clinical case definition of cholera
Cholera diagnosis is based on a standardised clinical case definition. Once established, this definition remains constant over the affected territory for the entire duration of the outbreak.
The World Health Organization (WHO) defines a cholera case as follows
World Health Organization. Global Task Force on Cholera Control. Surveillance Working Group. Interim Guidance to Document on Cholera Surveillance, 2017.
WHO cholera case definition
In areas where a cholera outbreak is declared: any person presenting with or dying from acute watery diarrhoea a Citation a. Diarrhoea is defined as 3 or more loose stools in a 24-hour period, with or without dehydration. .
The case definition should be disseminated to all heath facilities (hospitals, health centres, health posts) and community health workers to improve case detection.
Treatment is delivered in facilities specifically organized to manage cases of cholera. There are 3 types of facilities:
Cholera treatment centre (CTC)
The CTC is the most central in-patient facility with the largest patient treatment capacity (as a rough guide, 50 to 200 beds
A CTC should not exceed 200 beds. Above this number it becomes very difficult to manage the facility.
A CTC operates 24 hours a day and can manage any case of cholera, including severe cases requiring IV rehydration and less severe cases requiring oral rehydration only.
Patients requiring close follow up (e.g. pregnant women, infants) are preferably treated in a CTC.
Thus, a CTC is both:
- A referral facility for cases from peripheral facilities,
- A local treatment facility for people who live in the immediate vicinity, whatever the severity of their case.
Cholera treatment unit (CTU)
The CTU is a smaller, often decentralized, in-patient facility (as a rough guide, less than 30 beds). It operates 24 hours a day and treats patients requiring IV or oral rehydration.
Oral rehydration point (ORP)
ORPs are small decentralized facilities that provide out-patient care and operate only during daylight hours (8 to 12 hours/day).
They are mainly intended to:
1. Provide oral rehydration therapy: it is estimated that 70% of cholera cases develop mild to moderate diarrhoea and require oral treatment only. Early oral therapy helps avoid the appearance or aggravation of significant dehydration that would require hospitalization.
2. Arrange for transfer of severe or complicated cases to a CTC or CTU.
ORPs are not intended to provide care to severe cases however depending on the context (e.g. isolated setting or particularly long transport time) and human resources available (nurse present), they may organize the stabilization of severe cases (initiate IV rehydration) while transportation to the referral CTU or CTC is arranged.
The type, number, and location of treatment facilities to be deployed in response to the outbreak depend on the number of patients expected and beds needed (Section 2.7), the capacity of existing health facilities and partner organizations and the physical setting (e.g. refugee camp, urban or rural areas) in which the outbreak occurs (Chapter 4).
- 1.World Health Organization. Global Task Force on Cholera Control. Surveillance Working Group. Interim Guidance to Document on Cholera Surveillance, 2017.