Cholera

WHO and partners protect more than 1 million people from cholera

WHO and partners reach one million people with oral cholera vaccine in 2015.
WHO/S. Desai

11 April 2016 -- In 2015, more than 1 million people in 7 high-risk countries received the oral cholera vaccine, thanks to campaigns run by WHO and partners. This extraordinary measure was taken to contain several cholera outbreaks from spreading further in Bangladesh, Cameroon, Iraq, Malawi, Nepal, South Sudan and Tanzania.

Revised cholera kits

Cholera treatment centre in Zilmbabwe
WHO/D. Legros

The composition of the cholera kits has been reviewed by WHO and its partners. The contents of all modules have been updated and reorganised to be better adapted for field use in different settings.

The revised cholera kits are designed to help prepare for a potential cholera outbreak and to support the first month of the initial response. The overall package consists of six different kits, each divided in several modules. The kits and modules can each be ordered separately.

Cholera vaccine supply set to double, easing global shortage

Oral Cholera Vaccination Campaign in Southern Malawi, 2015.
WHO/L. Pezzoli

8 January 2016 -- The global supply of oral cholera vaccines (OCV) is set to double after WHO approved a third producer, helping to address global shortages and expand access in more countries. In 2013 the WHO created the world’s first OCV stockpile. Since then a total of 4 million doses to 11 countries have been used in humanitarian crises, outbreaks, and in endemic hotspots.

The Global Task Force on Cholera Control (GTFCC)

A young ...
WHO

The 2011 WHA 64.15 resolution “Cholera mechanisms for control and prevention” requested the WHO Director-General to revitalize the Global Task Force for Cholera Control (GTFCC) and to strengthen WHO’s work in this area, including improved collaboration and coordination among relevant WHO departments and other relevant stakeholders.

A revitalization process has been initiated in December 2012 and completed in early 2014. Terms of Reference have been agreed and are accessible below.

Cholera is an acute enteric infection caused by the ingestion of bacterium Vibrio cholerae present in faecally contaminated water or food. Primarily linked to insufficient access to safe water and proper sanitation, its impact can be even more dramatic in areas where basic environmental infrastructures are disrupted or have been destroyed. Countries facing complex emergencies are particularly vulnerable to cholera outbreaks. Massive displacement of IDPs or refugees to overcrowded settings, where the provision of potable water and sanitation is challenging, constitutes also a risk factor. In consequence, it is of paramount importance to be able to rely on accurate surveillance data to monitor the evolution of the outbreak and to put in place adequate intervention measures Coordination of the different sectors involved is essential, and WHO calls for the cooperation of all to limit the effect of cholera on populations.


Key messages

  • Cholera is transmitted through contaminated water or food.

Cholera is characterized in its most severe form by a sudden onset of acute watery diarrhoea that can lead to death by severe dehydration. The extremely short incubation period - two hours to five days - enhances the potentially explosive pattern of outbreaks, as the number of cases can rise very quickly. About 75% of people infected with cholera do not develop any symptoms. However, the pathogens stay in their faeces for 7 to 14 days and are shed back into the environment, possibly infecting other individuals. Cholera is an extremely virulent disease that affects both children and adults. Unlike other diarrhoeal diseases, it can kill healthy adults within hours. Individuals with lower immunity, such as malnourished children or people living with HIV, are at greater risk of death if infected by cholera.


Key messages

  • Cholera can rapidly lead to severe dehydration and death if left untreated.
  • Prevention and preparedness of cholera require a coordinated multidisciplinary approach.

The presence of V. cholerae in stools is confirmed through laboratory procedures. However, a new rapid diagnostic test (RDT), now available, allows quick testing at the patient's bedside. WHO is currently in the process of validating this RDT, to be able to include it on the list of its pre-qualified products.

In the meantime, WHO suggests that all samples tested positive with the RDT are re-tested using classic laboratory procedures for confirmation. Not all cases fitting the WHO clinical case definition need to be tested. Once an outbreak is confirmed, a clinical diagnosis using WHO standard case definition is sufficient1, accompanied by sporadic testing at regular intervals.


Key messages

  • Once Vibrio cholerae has been confirmed, the WHO clinical case definition is sufficient to diagnose cases. After that laboratory testing is required for antimicrobial sensitivity testing and for confirming the end of an outbreak.
  • Rapid diagnostic tests can facilitated early warning and detection of first cases.

Oral rehydration salts (ORS)

Efficient treatment resides in prompt rehydration through the administration of ORS or intravenous fluids, depending of the severity of cases. Up to 80% of patients can be treated adequately through the administration of ORS (WHO/UNICEF ORS standard sachet).

Use of antibiotics

Rapid and appropriate rehydration is the main management intervention for treating cholera cases, either orally for moderate cases, or intravenously for severe cases

Appropriate antibiotics can reduce the volume of diarrhoea due to cholera, reduce the volume of rehydration fluids needed, and shorten the duration of V. cholerae excretion. The current WHO recommendation is to give antibiotics only to cholera cases with severe dehydration.

Careful and regular laboratory monitoring of the antibiotic sensitivity of circulating strains is recommended in all settings, including during an outbreak, to guide treatment.

More information

In 2011, the World Health Assembly adopted resolution WHA 64.15 Cholera: mechanism for control and prevention, recognizing the re-emergence of cholera as a significant public health burden and threat.

Prevention

  • Provision of safe water, proper sanitation, and food safety are critical for preventing occurrence of cholera.
  • Health education aims at communities adopting preventive behaviour for averting contamination.

Control

The main tools for cholera control are:

  • proper and timely case management in cholera treatment centres;
  • specific training for proper case management, including avoidance of nosocomial infections;
  • sufficient pre-positioned medical supplies for case management (e.g. diarrhoeal disease kits);
  • improved access to water, effective sanitation, proper waste management and vector control;
  • enhanced hygiene and food safety practices;
  • improved communication and public information.

Cholera vaccines

There are two WHO prequalified oral cholera vaccines (OCV) currently available on the market. These vaccines were proven safe, effective and well accepted and are available for individuals aged one year and above. They are administered in two doses given at least 7 days apart.


Epidemiological information

Technical information

General information

Revised cholera kit

The revised cholera kits are designed to help prepare for a potential cholera outbreak and to support the first month of the initial response.

Contact us

For any request please send us an email to: csr@who.int