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close this bookCommunicable Disease Control in Emergencies - A Field Manual (WHO - OMS, 2003, 223 p.)
close this folderCHAPTER 2: PREVENTION
View the document(introduction...)
View the document2.1 SHELTER
View the document2.2 WATER
View the document2.3 SANITATION
View the document2.4 VECTOR CONTROL
View the document2.5 FOOD AND NUTRITION
View the document2.6 IMMUNIZATION


In many emergency situations, the displaced population must be sheltered in temporary settlements or camps. The selection of sites must be well planned to avoid risk factors for communicable disease transmission, such as overcrowding, poor hygiene, vector breeding sites and lack of adequate shelter. Such conditions favour the transmission of diseases such as measles, meningitis and cholera. Usually, the most suitable land is already occupied by the local population, leaving less desirable areas available to refugees or displaced people. Critical factors to consider when planning a site are: water availability, means of transport, access to fuel, access to fertile soil and for security reasons, a sufficient distance from national borders or frontlines.

The surrounding environment may also pose a threat to health in the form of vectors not encountered in the population's previous place of residence. In order to reduce such risks it is essential that site selection, planning and organization be undertaken as soon as possible.


Settlements should avoid the major breeding sites of local vectors, as well as marshy areas and flat, low-lying ground at risk of flooding. Preference should be given to gently sloping, well drained sites on fertile soil with tree cover, sheltered from strong winds. Local expertise and knowledge of the biology of the vectors should be considered, such as avoiding forested hills in some Asian countries where vectors proliferate. If not already sufficiently documented by national and local health services, the epidemiological characteristics of the area need to be assessed quickly.

The following criteria should be considered when assessing site suitability; other criteria may also be relevant in specific situations.

Water supply

The availability of an adequate amount of safe water throughout the year has proved in practice to be the single most important criterion for site location. The water source should be close enough to avoid transporting water by trucks, pumping it over long distances or walking long distances to collect insufficient quantities.


There must be enough space for the present number of emergency-affected population, with provision for future influxes and for amenities such as water and sanitation facilities, food distribution centres, storage sites, hospitals, clinics and reception centres.

Topography and drainage

Gently sloping sites above the flood level is preferred in order to provide natural drainage. Flat areas, depressions, swamp, river banks and lakeshore sites should be avoided. Windy sites are unsuitable, as temporary shelters are usually fragile.

Soil conditions

The soil type affects sanitation, water pipelines, road and building construction, drainage and the living environment (in terms of dust and mud). The most suitable soil type is one that will easily absorb human waste.


The site should be accessible at all times (e.g. for food deliveries, roads during rains).


The site area should have good vegetation cover if possible. Trees and plants provide shade, help to prevent soil erosion, allow recharge of the groundwater supplies and help in reducing dust. It may sometimes be necessary, however, to destroy poisonous trees or plants, for example where populations are accustomed to collecting berries or mushrooms.

Environmental health

Areas near vector breeding sites where there is a risk of contracting malaria, onchocerciasis (river blindness), schistosomiasis, trypanosomiasis, etc. should be avoided.


The site chosen should be in a safe area, sufficiently distant from national borders and combat areas.

Local population

The use of land for a camp can cause friction with local farmers, herdsmen, nomads and landowners. Some potential sites may have special ritual or spiritual significance to local people, and site selection must respect the wishes of the local population. Streams or rivers used for bathing and laundry may cause pollution far downstream; water abstraction will reduce flow rates. Indiscriminate defecation in the early stages may also pollute water supplies used by the local population.

Fuel supply

Fuel for cooking is an essential daily requirement. Options for fuel include wood, charcoal and kerosene. In practice, wood from surrounding forests is the most likely fuel. It is important to liaise closely with the local forestry department to control indiscriminate felling and collection.


It is important to prepare a master plan of the camp. The site plan should be sufficiently flexible to allow for a greater than expected influx of people. A 3-4% per year population growth rate must also be planned for.

Overdevelopment of some areas of the site must be avoided as it can cause health problems, especially for people who come from sparsely populated environments.

Tribal, ethnic or religious differences may exist within the camp population or between this population and the local people, or such groupings may develop or be strengthened with time. The camp must be planned in such a way that these divisions are honoured.

Site planning norms are presented in Table 2.3. The recommended figures for camp layout and services are only guidelines. In severely overcrowded, spontaneously settled camps it may be very difficult to achieve the recommended figures during the initial emergency phase and realistic compromises will have to be made. Nevertheless, the figures provide the basis for planning and are the targets at which to aim.

Table 2.3. Site planning norms

Area per person for collective activities

30 m2 a

Shelter space per person

3.5 m2 b

Distance between shelters

2 m minimum

Area for support services

7.5 m2/person

Number of people per water point


Number of people per latrine


Distance to water point

150 m maximum

Distance to latrine

30 m

Distance between water point and latrine

100 m


75 m every 300 m

a In practice this may be difficult to achieve, for example in areas with a high population density where little land is available. This figure includes roads, services, shelter, etc. but depends on the layout and terrain. It does not include land for livestock or agriculture. After space for covered shelter and support services, the remainder of the 30 m2/person area is for family plot space, latrines, washing and cooking areas, community space, roads, firebreaks, drainage, burial grounds and contingencies.

b For a five-person family this equals a shelter 6 metres by 3 metres in a plot 15 metres by 10 metres.


Community involvement should be continuously incorporated as an essential component of site planning and management and a resource that can be used to maximize the effectiveness of the intervention.


The layout of dwellings relative to each other can have a significant impact on security and cultural activities, and is important for the building of a social structure. It also affects the use of latrines and water points. Although shelters arranged in straight lines on a close grid pattern might appear to ease some aspects of camp management, such a pattern is not normally conducive to social cohesion. The camp should be organized into small community units or "villages" each of approximately 1000 people. Traditional living patterns should always be taken into account. Several villages can be combined to form a group; several groups can form a section; and there can be several sections in one camp. Table 2.4 shows the recommended structural organization for a camp setting. Each group or section will require a number of decentralized services, which are listed in Table 2.5.

The grouping of family plots into community units provides a defined, secure space within each unit. People know each other and strangers will stand out. The circumstances of an emergency may give rise to additional personal security risks. Women may be vulnerable to harassment and rape. Ethnic and factional divisions can provoke violent confrontations. In these circumstances the protection aspects of "shelter"' may mean keeping different refugee groups apart and/or the provision of secure compounds for particularly vulnerable refugees.

Table 2.4. Camp building blocks

1 family

= 4-6 people

16 families

= 80 people

= 1 community

16 communities

= 1250 people

= 1 block

4 blocks

= 5000 people

= 1 sector

4 sectors

= 20 000 people

= 1 camp


A minimum shelter space of 3.5m2 per person is recommended in emergency situations.

If possible, the emergency-affected population should build their own shelters, preferably using local materials such as timber, grass, bamboo, mud, sand and woven mats. Woven matting, natural fibre screens and bamboo make very good ventilated walls. When necessary, rolled-up plastic sheeting can be let down to make these walls water-, draught- and dust-proof. Tents and plastic sheeting provide reasonable protection from the elements, but with large numbers of people many units are required. Plastic sheeting may last only 6-9 months, depending on the quality used; it degrades as a result of exposure to the elements, especially sunlight. Canvas tents can last for up to two years if well maintained. The build-up of dirt or rainwater on the roof, or dirt on the walls, will shorten the life of a canvas tent.

It is best to plan the layout of shelter areas in community clusters adjacent to the relevant latrines, water points and washing areas. These community units should be as close as possible in design and layout to those with which the population is most familiar.


Consideration must be given to the location of roads, houses, food and water distribution points, emergency services (security, fire, medical), drains, washing areas, latrines and solid waste pits. Public buildings require access roads for vehicles and should be centrally located where possible.

Food distribution centres must be centrally located, with sufficient room for crowds of people waiting and for trucks delivering food. Good design can help considerably in crowd control and theft prevention. The main health facility must be in a safe and accessible place, preferably on the periphery of the site to allow for future expansion and to avoid overcrowding.

A site for a cholera treatment centre must be identified in advance, separate from other health facilities and in an area where water supplies cannot be contaminated.

Support facilities must be located away from dusty or potentially dangerous major access roads.

Table 2.5. Main facilities on settlements




Community health centres

Coordination offices

Bathing and washing areas


Social centres



Hospital (for large camps)

Recreation space

Tracing centres

Supplementary feeding centres

Therapeutic feeding centres

Religious buildings

Food distribution centres

Water points

Training centres


Sanitation offices

Roads and firebreaks



A reception area must be set up outside the settlement to receive and register new arrivals before they become integrated within the camp. The registration site should preferably be a large, flat, open space with a water supply and latrines or defecation areas. Temporary first-night shelter and land for accompanying animals may be needed.


Market areas are important trading and social centres, but they can pose health risks where food and drink is for sale. The planning and layout of such areas are very important. If possible the market should be outside the camp, or several small market areas can be established. Vector control, waste collection and disposal measures need to be particularly stringent at market areas.

Markets must be divided into food and non-food areas. Food areas should be further divided into areas for raw and processed foods.

Areas must be provided for the slaughter of livestock, if possible with a concrete slab with good drainage to carry away blood and animal droppings (although one needs to ensure that this does not drain directly into a watercourse).


Generators and pumps should be located away from family dwellings and the buildings housing them should be soundproofed, with sufficient ventilation for the escape of exhaust fumes. Traffic should be limited to main routes.


Coordination between the various organizations working in the emergency is essential in order to maximize positive impact on the population by means of effective management and integration of relief activities.

The following steps are necessary to achieve this objective:

· establish clear leadership;
· create a coordinating body;
· ensure that programme activities are shared by agencies;
· clarify the roles and responsibilities of all partners;
· prevent duplication of activities;
· establish good communication channels;
· ensure that all needs are addressed; and
· create and implement agreed common policies, standards and guidelines.


Continued liaison with local communities is essential. The influx of emergency-affected populations into their area means that they are now affected by the emergency. There is a real risk of generating resentment if local people feel that the emergency-affected populations are better served than they are. There may be a need to provide medical or other assistance to local communities, both to ensure equity and to prevent the spread of disease.