X.9 Cholera Prevention and Epidemic Management

Cholera is a faecal-oral disease that causes infection of the small intestine leading to severe watery diarrhoea, rapid dehydration, and death if left untreated. There are many ways to prevent and control the spread of cholera, which requires actions both inside the health sector and beyond, including access to safe water, sanitation and good hygiene practices (WASH). Cholera occurs in both humanitarian emergency settings and in endemic settings where cholera outbreaks occur regularly among the same populations, usually coinciding with the rainy season. However, in most cases, cholera outbreaks happen to impact nations/regions already dealing with a pre-existing fragile context, including poor hygienic conditions, limited access to drinking water and to sanitation facilities. Although the focus here will be mainly on cholera in emergencies it is important to recognise that where possible, efforts to control cholera should seek to build long-term systems and consider the longer-term prevention beyond reactive approaches X.5.

The following key messages contain important background information for all those dealing with cholera:

  • Cholera is caused by the bacterium Vibrio cholera entering the body in the faecal-oral pathway through the consumption of water and/or food that has been contaminated through poor water and sanitation systems, and inappropriate hygienic practices, such as the absence of handwashing with soap after defecation.
  • Most infected people do not develop any symptoms. They are called “healthy carriers” and can spread cholera easily if water sources become contaminated with faeces containing the bacterium, when hygiene conditions are poor and open defecation is prevalent.
  • Cholera must be treated in special units called Cholera Treatment Centres (CTC) in order to prevent the spread of the disease in the community.
  • Every single case of cholera should be investigated in order to assess and break the path of transmission.
  • Faeces and vomit produced by cholera patients are highly infectious and should be appropriately and safely handled and disposed of (e.g. disinfection with chlorine solution or lime).
  • While cholera can spread quickly through the environment, there are several known and effective ways to halt transmission. Practices that isolate faeces from food and water such as treating and storing water safely and using improved sanitation facilities are essential to control a cholera outbreak.
Refers to (semi-solid) excrement that is not mixed with urine or water. Depending on diet, each person produces approximately 50–150 L per year of faecal matter of which about 80 % is water and the remaining solid fraction is mostly composed of organic material. Of the total essential plant nutrients excreted by the human body, faeces contain around 39 % of the phosphorus (P), 26 % of the potassium (K) and 12 % of the nitrogen (N). Faeces also contain the vast majority of the pathogens excreted by the body, as well as energy and carbon rich, fibrous material.The liquid produced by the body to rid itself of nitrogen in the form of urea and other waste products. In this context, the urine product refers to pure urine that is not mixed with faeces or water. Depending on diet, human urine collected from one person during one year (approx. 300 to 550 L) contains 2 to 4 kg of nitrogen. The urine of healthy individuals is sterile when it leaves the body but is often immediately contaminated by coming into contact with faeces.A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The elimination of (pathogenic) microorganisms by inactivation (using chemical agents, radiation or heat) or by physical separation processes (e.g., membranes). See POST Sanitation facilities that ensure hygienic separation of human excreta from human contact. The common name for calcium oxide (quicklime, CaO) or calcium hydroxide (slaked or hydrated lime, Ca(OH)2). It is a white, caustic and alkaline powder produced by heating limestone. Slaked lime is less caustic than quicklime and is widely used in water/wastewater treatment and construction (for mortars and plasters). It can also be used for on-site treatment of faecal sludge. See S.17Any cellular or non-cellular microbiological entity capable of replication or of transferring genetic material (e.g. bacteria, viruses, protozoa, algae or fungi). Any substance that is used for growth. Nitrogen (N), phosphorus (P) and potassium (K) are the main nutrients contained in agricultural fertilisers. N and P are also primarily responsible for the eutrophication of water bodies. Practice of defecating outside in the open environment. An organism or other agent that causes disease.A diverse group of unicellular eukaryotic organisms, including amoeba, ciliates, and flagellates. Some can be pathogenic and cause mild to severe illnesses. The means of safely collecting and hygienically disposing of excreta and liquid wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment. The organic molecule (NH2)2CO that is excreted in urine and that contains the nutrient nitrogen. Over time, urea breaks down into carbon dioxide and ammonium, which is readily used by organisms in soil. It can also be used for on-site faecal sludge treatment. See. S.18An infectious agent consisting of a nucleic acid (DNA or RNA) and a protein coat. Viruses can only replicate in the cells of a living host. Some pathogenic viruses are known to be waterborne (e.g., the rotavirus that can cause diarrheal disease). Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration. Agent infectieux constitué d’une substance nucléique (ADN ou ARN) et d’une couche de protéines. Les virus ne peuvent se répliquer que dans les cellules d’un hôte vivant. Certains virus pathogènes sont connus pour être d’origine hydrique (par exemple le rotavirus qui peut provoquer des maladies diarrhéiques).

WASH interventions

Provision of WASH services are key elements of both the prevention of and response to cholera outbreaks. In cholera endemic and risk prone areas, significant efforts need to be made to ensure safe and adequate water supply and disinfection, water quality monitoring, hygiene promotion, sanitation and safe excreta disposal at household and community levels and in CTCs and healthcare facilities. In terms of sanitation, the focus should be on the following:

Improving access to and use of safe excreta disposal: Faecal matter needs to be kept away from water and food (containment) and cholera bacteria that could potentially contaminate food and water need to be killed prior to consumption ( disinfection). Suspected or confirmed cholera cases have to be provided with separate toilets or latrines that are not used by other individuals. A sufficient number of functioning, accessible, appropriate and safe toilets for staff, patients, and caregivers (see box) need to be ensured (including regular cleaning and maintenance at least daily) that do not contaminate the health-care setting or water supplies.

Environment free from human excreta: It should be ensured that latrines with functional handwashing facilities  are used and kept clean; that people, including children, do not defecate in the open and that all faeces are disposed of safely in a latrine or buried X.11. Excreta disposal facilities need to be provided in markets, public places and institutions with functioning and well-managed Handwashing Facilities U.7 . They should be culturally appropriate and a sustainable cleaning and management system should be established for public and communal facilities.

Handwashing: Handwashing Facilities U.7 must be available and accessible; and proper handwashing practices must be promoted, particularly at key times (after latrine use, after cleaning a child’s bottom, before cooking and feeding, after caring for a cholera patient).

Personal protective equipment: Personal protective equipment (e.g. boots, masks, gloves, clothing etc.) must be provided for those involved in operation and maintenance along the sanitation service chain.

Food hygiene: Hygiene promotion activities need to include the promotion of food hygiene (proper preparation, reheating and storage of food, cleaning of cooking utensils).

Chlorine solution disinfection: Different chlorine solutions (with different percentages of free residual chlorine) must  be available for different purposes: (1) 0.05 % for handwashing with soap, skin disinfection, laundry (patient and administrative), latrines, kitchen, mortuary and waste area (or alternatively alcohol-based hand rub), (2) 0.2 % for disinfecting floors, objects, beds, clothes, kitchen utilities of patients, and (3) 2 % to add to excreta/vomit for disinfection and to wash dead bodies (or alternaively lime treatment).

WASH related cholera relief interventions can be broadly distinguished between households, institutions, and health care facilities.

Households:
Risk of contamination is particularly high in house- hold settings, and household members of cholera patients are 100 times more at risk of contracting disease than other community members.
  • Excreta (which may contain cholera) needs to be properly disposed of and separated from the human living environment and water sources.
  • An excreta management system needs to be set up, even in the early stages of an emergency.
  • Sanitation solutions that do not contaminate groundwater need to be identified.
  • Promotion of handwashing with soap, especially before eating, cooking, after cleaning a baby, child or adult’s bottom, after using the latrine, and when caring for a sick person.
  • Promotion of food hygiene (proper preparation, reheating and storage of food, cleaning of cooking utensils).
  • Promotion of water treatment and storage (water containers need to be covered and regularly cleaned, and water should be removed using a tap or cup with a handle so that hands do not come in contact with water).
  • Latrines need to be regularly cleaned and maintained, and privacy and safety ensured to encourage use.
  • If someone dies of cholera (or a condition suspected to be cholera), the body should be touched as little as possible followed by hand- washing with soap. Trained personal should be asked to assist with safe and proper burial. Special funeral guidelines have to be adopted according to and respecting local traditions.
Institutions:
  • Public places should be equipped with gender- segregated sanitation facilities.
  • All sanitation facilities should have functioning handwashing and bathing facilities if needed.
  • Handwashing stations with soap (U.7) should be available in all public places, especially near toilets or food establishments.
  • Signs/posters can help encourage people to wash hands with soap after toilet use and before cooking/eating.
  • Food safety should be addressed in institutions/public places (e.g. schools, government build- ings, and markets).
Healthcare Facilities:
  • In CTCs, typically established when an outbreak is suspected or confirmed, many patients are too weak to use a toilet. Buckets (10–15 L) are placed under a purpose-built hole in the cholera bed and at the bedside. Buckets can be raised on a block to prevent splashing of the surround- ing area. Approximately 1 cm of 2 % chlorine solution should be put into the bucket before it is placed under the bed. Buckets should be emp- tied in nearby toilets used by cholera patients. After collection and disposal of excreta, buckets should be rinsed with 0.5 % chlorine solution, disposing of rinse water in drains or a toilet.
  • Recommended number of latrines is 1 for every 20 persons in observation, 1 for every 50 patients in hospitalisation plus 1–2 for staff.
  • Suspected and confirmed cholera patients should be isolated from other patients.
  • Separate facilities should be available for cholera patients to prevent spread of infection.
  • All liquid human waste is disposed of in a latrine, or is buried.
  • Easy to clean plastic slabs are recommended.
  • Safe containment of excreta and faecal sludge should be ensured on-site; the toilets should not be connected to a sewer network to avoid spreading the disease.
  • Safe water should be available in sufficient quantities for patients, healthcare providers, for cleaning and disinfection within the facility.
  • For cholera outbreaks, appropriate personal protective equipment needs to be provided and used.
  • Dead bodies should be prepared and buried in a way that avoids disease transmission.
Consists of urine and faeces that are not mixed with any flushwater. Excreta is relatively small in volume, but concentrated in both nutrients and pathogens. Depending on the characteristics of the faeces and the urine content, it can have a soft or runny consistency.Refers to (semi-solid) excrement that is not mixed with urine or water. Depending on diet, each person produces approximately 50–150 L per year of faecal matter of which about 80 % is water and the remaining solid fraction is mostly composed of organic material. Of the total essential plant nutrients excreted by the human body, faeces contain around 39 % of the phosphorus (P), 26 % of the potassium (K) and 12 % of the nitrogen (N). Faeces also contain the vast majority of the pathogens excreted by the body, as well as energy and carbon rich, fibrous material.Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.The liquid produced by the body to rid itself of nitrogen in the form of urea and other waste products. In this context, the urine product refers to pure urine that is not mixed with faeces or water. Depending on diet, human urine collected from one person during one year (approx. 300 to 550 L) contains 2 to 4 kg of nitrogen. The urine of healthy individuals is sterile when it leaves the body but is often immediately contaminated by coming into contact with faeces.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system: User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U). A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. Simple, single cell organisms that are found everywhere on earth. They are essential for maintaining life and performing essential “services”, such as composting, aerobic degradation of waste, and digesting food in our intestines. Some types, however, can be pathogenic and cause mild to severe illnesses. Bacteria obtain nutrients from their environment by excreting enzymes that dissolve complex molecules into more simple ones which can then pass through the cell membrane. The process by which biodegradable components are biologically decomposed by microorganisms (mainly bacteria and fungi) under controlled aerobic conditions. The elimination of (pathogenic) microorganisms by inactivation (using chemical agents, radiation or heat) or by physical separation processes (e.g., membranes). See POST The utilisation of products derived from a sanitation system. Water that is located beneath the earth’s surface. The common name for calcium oxide (quicklime, CaO) or calcium hydroxide (slaked or hydrated lime, Ca(OH)2). It is a white, caustic and alkaline powder produced by heating limestone. Slaked lime is less caustic than quicklime and is widely used in water/wastewater treatment and construction (for mortars and plasters). It can also be used for on-site treatment of faecal sludge. See S.17Any cellular or non-cellular microbiological entity capable of replication or of transferring genetic material (e.g. bacteria, viruses, protozoa, algae or fungi). Any substance that is used for growth. Nitrogen (N), phosphorus (P) and potassium (K) are the main nutrients contained in agricultural fertilisers. N and P are also primarily responsible for the eutrophication of water bodies. A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated. An organism or other agent that causes disease.A diverse group of unicellular eukaryotic organisms, including amoeba, ciliates, and flagellates. Some can be pathogenic and cause mild to severe illnesses. The means of safely collecting and hygienically disposing of excreta and liquid wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment. Waste matter that is transported through the sewer. An open channel or closed pipe used to convey sewage. See C.3 and C.4 User interface used for urination and defecation. The organic molecule (NH2)2CO that is excreted in urine and that contains the nutrient nitrogen. Over time, urea breaks down into carbon dioxide and ammonium, which is readily used by organisms in soil. It can also be used for on-site faecal sludge treatment. See. S.18An infectious agent consisting of a nucleic acid (DNA or RNA) and a protein coat. Viruses can only replicate in the cells of a living host. Some pathogenic viruses are known to be waterborne (e.g., the rotavirus that can cause diarrheal disease). Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration. Composés d’urine et de fèces non-mélangées à de l’eau de chasse. Leur volume est peu important, mais ils sont concentrés en nutriments et en agents pathogènes. Selon la qualité des fèces, leur consistance peut être molle ou liquide.Waste matter that is transported through the sewer. Agent infectieux constitué d’une substance nucléique (ADN ou ARN) et d’une couche de protéines. Les virus ne peuvent se répliquer que dans les cellules d’un hôte vivant. Certains virus pathogènes sont connus pour être d’origine hydrique (par exemple le rotavirus qui peut provoquer des maladies diarrhéiques).
arrow_upward