G. Sanitation and Environmental Health Services
While the discussion in this section emphasizes DP camps to a great extent, most of the material is also applicable to assisting with the sanitation concerns of small communities impacted by disaster or conflict. The disruption and overcrowding of people accustomed to living in less crowded conditions in their own homes makes sanitation a critical issue. Indiscriminate disposal of human excreta and other waste products poses serious threats to the health of individuals, families, and the community. In a DP emergency, sanitation facilities to which individuals were accustomed are no longer available. Basic services are often lacking, and habits may have to be changed.
For this reason, an effective environmental health program must be established to include the following: provision of safe water; disposal of human excreta, wastewater, and garbage; insect and rodent control; safe food-handling practices; and site drainage. These services and the provision of health care are interrelated and should be considered together.
An acceptable and practical system for the disposal of human excreta is the key to reducing health hazards. The system must be developed in cooperation with the DPs and be culturally appropriate, even if circumstances necessitate a departure from traditional practices. The provision of special public health or hygiene education may be required to ensure that the system will be used by the displaced population.
2. Importance of Organization, Integration, and Selection
Environmental sanitation will be a very important consideration in campsite layout, and its organization and operation must be integrated with other community services. Expert advice should be sought from a public health engineer or environmental health specialist familiar with the habits of displaced people and the local population, and experienced with DP emergencies.
Good sanitation depends to a great extent on attitudes of the community and the people who run the system. The overall system and its services should be able to operate effectively with a minimum of outside involvement. Therefore, selected DPs must be trained to run the sanitation and environmental programs.
The most common cause of failure of a sanitation system is the establishment of the wrong system, often as a result of inadequate involvement of the camp population and a failure to take all relevant factors into consideration.
Breakdown of sanitation systems is often caused by inadequate maintenance, even for properly designed and installed systems. Poor maintenance will lead to latrine failures, contamination of the environment, and a high risk of infection and disease. Regular inspection and maintenance of latrines should be enforced. The best guarantee of proper maintenance is the allocation of latrines to individual families.
Even when in working order, latrines will not be used unless they are clean. Individual families should be responsible for the cleanliness of their own units. If communal latrines are unavoidable, the camp management must establish an effective program of latrine cleaning and maintenance, which may include compensating individuals who are responsible for keeping them clean and operational on a daily basis. Particular attention must be given to the maintenance and cleanliness of latrines serving community facilities such as feeding and health centers. It should be noted that disinfectants should not be poured into pits or tanks of latrines as these chemicals will interfere with natural biological degradation processes. Instead, the regular addition of soil, ashes, or oil may be used to control insect breeding and reduce odor.
A public health education program emphasizing the importance of sound sanitation practices should be established. The link between excreta contamination and disease must be clearly understood by all, including children. Children are the main excreters of many pathogens that cause diarrhea. Because children are often uncomfortable using unfamiliar latrines, particular care will be needed to ensure that latrines are safe and physically suitable for children.
3. Disposal of Excreta
Safe disposal of excreta is critical because agents of a large number of infectious diseases are passed from the body in excreta. These excreted infections fall into four main groups: viruses, bacteria, protozoa, and worms (helminths). Excreta, unless properly isolated, can also provide a breeding ground for insects, which may act as either direct or indirect transmitters of disease.
Links between diseases, infections, means of transmission, and the sanitation system must be kept under constant surveillance. But the links are not always the most obvious. For example, an important human link in transmission of an infection is the carrier who shows little or no sign of disease. Conversely, people in an advanced state of disease may have minimal impact on disease transmission, as those around them will be aware of the danger.
Human waste is more dangerous than animal waste; therefore, the safe disposal of human excreta is more important than the disposal of animal waste. Human feces are normally of much more concern than urine. In areas of Africa and the Middle East where the Schistosoma haematobium species of bilharzia exists, however, and in all areas where typhoid is common and endemic, proper disposal of urine is also extremely important.
a. Selection of a System-Immediate Considerations
The selection of an appropriate excreta disposal system requires consideration of a number of factors. In an emergency, however, time is the critical factor. Pollution of the environment by excreta, with all its attendant risks, cannot be stopped without immediate sanitation measures. Thus, the range of choices is always much more limited at the very outset of an emergency. Weeks or months cannot be lost in waiting for expert advice, construction to be completed, or material to arrive. In an emergency situation, provide systems to meet immediate needs, which can be improved or replaced later.
Emergency conditions may dictate at least the initial use of trench latrines. These can be dug quickly and need less space than individual family units. While very shallow trenches may be an initial quick solution, deeper trench latrines are much more effective. Where space and soil conditions allow, the simplest and most common individual family unit is the pit latrine.
Once a temporary system has been established, more time and care should be expended to establish the most appropriate waste disposal system. Two main factors will affect the choice of an excreta disposal system: the traditional sanitation practices of the displaced people and the physical characteristics of the area, including the geology, availability of water, rainfall, and drainage. Failure to take proper account of any of these factors can cause the system to rapidly become a health hazard. Above all, cleanliness of latrines and their ease of access will determine whether or not they are used.
First, it must be determined how the DPs can modify their traditional practices to reduce health hazards during the emergency situation. More than 40 percent of the world’s population does not have access to a sanitary form of excreta disposal. Traditional practices and other factors must be considered at the planning stage and will directly affect the type of system to be established. Other cultural factors to consider include:
- Previous sanitation system and practices.
- Method of anal cleansing.
- Preferred position (sitting or squatting).
- Need for privacy and security, particularly for women and children.
- Segregation of sexes and other groups or individuals with whom sharing a latrine is culturally unacceptable.
- Cultural practices for children.
- Cultural taboos (e.g., avoiding contact with anything that may have touched excreta of others).
- Social factors, including likelihood of community action to ensure proper use of proposed system.
- Cultural needs for special orientation (direction) of latrine.
- Systems used locally in neighborhood of site.
Arrangements must be made to ensure the availability of appropriate anal-cleansing materials and hand washing facilities at or near all latrines. Such facilities are essential for the maintenance of individual and community hygiene. Also, latrines must be safe for children and women and be accessible at night. For individual units, families may provide their own lamps, but some form of lighting should be provided for communal units. In some cases, guards may be needed near the latrines to ensure security.
b. Immediate Action
The first group of DPs arriving at a site should construct a disposal system adequate for their immediate needs. Without proper facilities, DPs are likely to defecate indiscriminately, contaminating their environment and possibly their water supply. In consultation with community leaders, the first step is to localize excreta; that is, control indiscriminate defecation. If space allows, designate an area or areas away and downwind from dwellings, but accessible and in close proximity. Fence the area(s), ensure privacy, and provide a shallow trench and spades, if possible. Locate these areas where surface runoff during rain will not cause contamination to the shelter area or water sources, and protect them with cutoff ditches.
A publicity campaign will be required to encourage the population to use specified areas and not defecate indiscriminately near dwellings. Measures must also be taken to prevent defecation or urination in or near the water supply. Immediate action in both regards can significantly reduce public health hazards.
If the ground is flooded or marshy or has a high water table, arrangements must be made as soon as possible to physically contain the excreta. Under such conditions, the location of the area, away from dwellings and the water source, is very important. Pending a proper containment system, a simple raised structure (e.g., a wooden stage some 50 cm high) can prevent the population from contaminating their environment with excreta. Empty 200-L (45-gal) oil drums can also be used if one end of the drum is cut out and then inserted open end down into a hole that is as deep as the water allows, with the last half meter of the drum left aboveground. A small hole should be cut into the aboveground end of the drum to transform it into a squatting plate. These options should be viewed as very short-term sanitation interventions.
In hot, dry climates where sufficient space is available, localized defecation areas located away from dwellings may be the best short-term arrangement, as heat and sunlight render the feces harmless with time. Black rock is the best surface. Under these conditions, potential health hazards in the area (e.g., an increased number of rats) should be periodically reviewed.
If the camp is on the coast, DPs may choose to defecate in the water. While this practice is less harmful than to indiscriminately defecate on land, it should be discouraged unless no other option is available. The dangers of defecating in the water increase greatly with numbers. Such practices contaminate the high-water line, and increase the health hazards of washing in the sea. Defecation in bays, estuaries, or lagoons where fish or shellfish are caught should be greatly discouraged, as this may be a source of infection in seafood.
c. Longer Term Options
For a number of reasons, expert advice is required to develop the most appropriate waste disposal system. The nature of the soil will be important; if the soil is highly impervious to water, some systems should be excluded from consideration. The availability of water and cultural considerations must also be considered. Many simple options, if properly constructed and maintained, will meet all public health requirements. In most emergencies, two main types of latrines are possible, even for DPs unaccustomed to them. The most common type is the dry latrine, such as a trench, pit, or hole in the ground. More elaborate pour-flush latrines use small quantities of water to flush wastes out of the toilet trap. Other systems are based on the composting of excreta.
d. Latrine Styles and Considerations
Three basic latrine styles are available: individual family units, centralized units with each latrine allocated to an individual family, and communal systems. Individual family units are the preferred solution, because people will always make more of an effort to clean their own latrine than they will to clean a communal facility.
To determine the most appropriate latrine style, consideration must be given to a number of factors, such as the number and siting of latrines, population density, soil, available water, drainage, and construction materials.
- Number and Siting of Latrines
- As a rule, at least one latrine (drop hole) should be provided for every 20 people. Latrines should be located at least 6 m from dwellings, 10 m from feeding and health centers, and at least 30 m from wells or other drinking-water sources. Although all these distances depend on latrine and soil type, latrines should be located no more than 50 m from users. If people must walk a considerable distance to a latrine, they will defecate in a more convenient location, regardless of the health hazard.
- Even when in working order, latrines will not be used unless they are clean. Emergency conditions may dictate at least the initial use of trench latrines. The following standards for pit latrines are desirable.
Not more than four families per latrine without organized, paid maintenance. Latrines should be located at least 6 m from dwellings, 10 m from feeding and health centers, and at least 30 m (and preferably farther) from wells or other drinking-water sources, but no more than 50 m from users.
Trench latrines, shallow (for a few days)
30 cm wide by 1 m to 1.5 m deep by 3.5 m long per 100 people
Trench latrines, deep (for a few months)
70 cm to 100 cm wide by 2 m to 2.75 m
deep by 3.75 m long per 100 people
- Population Density
- Population density will affect the space available for the excreta disposal system and thus the type of system. If latrines are too close to dwellings, there may be insufficient space for individual units. Overcrowding may cause major health hazards and must be considered in site planning. The camp layout should be determined, among other things, by the needs of the most suitable sanitation system, not vice versa. Space must be available for replacement latrines where necessary.
- Soil conditions can vary over a short distance of land, thus requiring a thorough survey of the area. The nature of the soil also may exclude certain options. For example, rocky soil may prevent the digging of pit-type systems. Sandy soil will demand special actions to prevent sidewall collapse of pits. Impervious clay soils may exclude any system dependent on seepage. Account should also be taken of the difference between dry-and wet-season soil conditions. If the ground freezes in winter, the choice of systems may be limited. Where a high water table exists, even only seasonally, care must be taken to ensure that the water is not contaminated by seepage from the latrines. Excreta must be contained in flood or swampy conditions.
- Available Water
- The amount of available water will determine whether disposal systems requiring water are a possibility. These systems are generally more expensive than those not requiring water. Because DPs’ situations are often characterized by a lack of reliable water sources, the excreta disposal system should not be dependent on water availability. Whatever the system, however, water should be available for anal cleansing and hand washing. The availability of water for hand washing is a critical consideration that should not be overlooked.
- Because all camps experience rain from time to time, anticipate where surface runoff will flow and how to divert it by cutoff ditches. The possibility of flooding should also be considered and drainage provided if necessary. If floodwater enters latrines, large areas may be contaminated.
- Construction Materials
- Construction material will be needed to build some types of disposal systems, for example, those with walls and roofs. DPs unaccustomed to latrines generally prefer a large enclosure with no roof. Strong arguments can be made, however, for covering latrines to prevent rainwater from filling the latrine and causing contamination around it or weakening the surroundings. Roofs should provide proper drainage away from the latrine. Special measures will be necessary to manufacture squatting or sitting slabs, water traps, and other equipment for pour-flush systems, if these are not available locally. Where DPs have an established method of covering latrines (e.g., with a wooden lattice), such techniques are generally preferred, even if these methods are more difficult to clean. A number of simple techniques exist for making special plates on site, for example, with reinforced cement and preformed molds. Local materials should be used for the structure as well as for reinforcing the pit where necessary. Above all, the latrine must be easy to clean, and the surfaces around the drop hole must be washable.
4. Wastewater (Greywater), Garbage, and Dust
a. Wastewater (Greywater)
Excess water from washing, bathing, and food preparation is considered wastewater or greywater. It can be a problem if not drained away. Without good drainage, this water will collect in malodorous, stagnant pools that provide breeding places for insects, especially mosquitoes. Wastewater should generally not be permitted to enter latrines, as this will cause the latrine pit or trench to fill very quickly. If latrine pits or trenches are sufficiently large and the amount of water used for bathing is relatively small, however, DPs should be allowed to use the latrine area for bathing because it provides privacy and drainage. In most circumstances, separate bathing and clothes-washing areas with duck-boards or stones and proper drainage should be constructed.
Because all communities generate garbage, established routines for the control, storage, collection, and disposal of solid wastes will be required. These needs must be reflected in initial site planning. If uncontrolled, the accumulation of garbage is both unpleasant and unhealthy. The potential for diseases transmission by rodent and insect vectors increases with improper garbage disposal. Free-range chickens, goats, and pigs will help control garbage; dogs will spread it.
The following suggestions for garbage storage, collection, and disposal are of particular concern for high-density camps, where the problem and dangers are greatest.
Storage. To store garbage, containers made of metal or plastic with a minimum capacity of 50 L should be provided. A 200-L oil drum cut in half is often used. Storage containers should have lids and drainage holes in the bottom. A ratio of 1 container per 10 families has proven to be effective. Containers should be placed throughout the camp so that no dwelling is located more than 15 m from a garbage container.
Collection. The collection of garbage from containers should take place on a regular, daily basis, if possible. Daily collection arrangements must be made to collect medical waste and wastes from feeding centers.
Disposal. Garbage can be disposed of by burying it at designated locations on the site or removing it from the site. Open dumping of garbage on site should be avoided. If garbage has to be dumped, it should be dumped far from the settlement areas. The ashes should be covered with a layer of soil after each burning.
The safe disposal of medical waste requires particular attention. Needles and scalpels are especially dangerous. Medical waste must be tightly controlled. It should be collected, transported, and disposed of separately. Medical waste should always be burned without delay. This disposal should be done in an incinerator to ensure high temperature and complete burning. Designated areas where medical waste and/or ashes are to be handled should be located far from dwellings and fenced to restrict access.
Large amounts of dust carried through the air can contaminate food and be harmful to human health by irritating eyes, the respiratory system, and skin. Dust can also harm some types of equipment used on site. The best preventive measure is to stop the destruction of vegetation on the site. Dust control can be achieved by spraying roads with water or oil, especially around health facilities and feeding centers, as well as limiting or banning traffic from certain areas.
5. Insect and Rodent Control
The environment in a DP emergency is conducive to the proliferation of disease vectors, typically insects and rodents that can also destroy or spoil large quantities of food. Flies tend to breed in areas where food or human excreta are present, and mosquitoes thrive around stagnant water. Because the proliferation rate for both is very high (the life cycle from egg to adult can take less than 2 weeks), the control of flies and mosquitoes is critical. Rats are also a problem as they live in areas with plentiful food, garbage, and cover. As a result of overcrowding and inadequate personal hygiene, lice, fleas, mites, ticks, and other arthropods may also cause health problems.
Reducing the numbers of flies, mosquitoes, and rodents quickly in an emergency may be difficult, but physical screens can be used to control the immediate problem. The most effective long-term method of controlling insects and rodents is to make the environment less favorable for the vectors. This task is done by improving personal hygiene, sanitation, drainage, garbage disposal, and food storage and handling practices. Practical measures include removing stagnant wastewater, collecting garbage on a regular basis, using oil in latrines, and providing soap and sufficient water for washing. These measures should be integrated into a regularly inspected program with other health measures.
Vector control methods using insecticides and poisons can be dangerous. Like all methods involving chemicals, instructions for use should be closely followed, and the application supervised and monitored by specialists. All major efforts to control insects and rodents must be closely coordinated with national programs and practices, especially with the national malaria control program. Although several different methods may be used, insect breeding grounds and the dwellings of the DPs may be sprayed. Since insects may already have, and can quickly develop, a resistance to chemicals, a rotation system using different sprays may be necessary. Local knowledge of existing resistance is required. Poison and traps may be used against rats in food storage and handling areas. Particular care must be taken in disposing of dead rats, which may carry plague-bearing fleas. Chemical spraying and rodent poisons can be dangerous to humans.
The body louse, usually found on inner clothing seams, is the only proven vector of louse-borne (epidemic) typhus and epidemic relapsing fever. If a serious increase in body louse infestation occurs, quick action is required by properly trained personnel. This action generally includes dusting individuals’ inner clothing and bedding with an insecticide or fumigating clothing. Widespread resistance of lice to some insecticides is a challenge, and expert local advice must be sought. Mass washing of clothing is not recommended as a water temperature of at least 52 degrees Celsius must be maintained to kill the lice.
The following is a listing of vectors and their potential health risks.
Eye infections (particularly among infants and children), diarrheal diseases, onchocerciasis
Malaria, filariasis, dengue, yellow fever, encephalitis
Scabies, scrub typhus
Epidemic typhus, relapsing fever
Plague (from infected rats), endemic typhus
Relapsing fever, spotted fever
Rat bite fever, leptospirosis, salmonellosis
DP camps are often overcrowded, are built of highly combustible shelter materials, and have many individual cooking fires. For these reasons, camps are very vulnerable to major fires. Measures to prevent and control fires must be considered from the start of emergency assistance at DP camps.
The most basic and effective measure to prevent a major fire is the proper spacing and arrangement of all buildings to provide firebreaks. Other measures include allowing individual fires for cooking only and building fires outdoors only, if possible. If cooking must take place indoors, and especially in wooden or wattle-and-daub buildings, the cooking area should be protected with fire-resistant sheeting if possible. If large-scale cooking takes place indoors (e.g., in a supplementary feeding center), fire-resistant ceilings and walls are mandatory. Fire retardants can be applied to thatched roofs in dwellings. Proper precaution must be taken when storing and using fuels. Highly flammable synthetic materials should be avoided.
When fighting a large fire with scarce resources, the first priority is to contain it, rather than put it out. Fires can be controlled in the first few minutes with modest resources, providing quick action is taken. To control fires, an alarm system, firefighting teams, and beaters must be organized in advance and plans prepared. Water is generally not available in sufficient quantities or at adequate pressure for the control of major fires; however, sand or other loose mineral soil material can be an effective method of control. A new fire-break should be created by taking structures down manually or with a bulldozer if available.
7. Funeral Services
Dead bodies present a negligible health risk in almost all circumstances. If the cause of death is typhus or plague, and the body is infested with infected lice or fleas, appropriate precautions must be taken as the vector organisms are still capable of transmitting disease. Also, as a precaution, the bodies of cholera victims should be washed and treated with an appropriate disinfectant in preparation for funerals and burial or cremation. Large funeral feasts should be discouraged in the case of cholera victims, and individuals preparing bodies for the funeral should not prepare food. Special precautions must also be taken with the bodies of victims of hemorrhagic fever.
Suitable arrangements for handling dead bodies with dignity and respect are required from the start of a DP emergency. The mortality rate after a new DP influx may be higher than under "normal" conditions. Also, bodies must be protected from rodents, animals, and birds. Authorities should be contacted immediately to ensure compliance with national procedures and provide assistance as necessary. The necessary space for burial should also be considered at the site planning stage, particularly in crowded conditions.
Whenever possible, traditional and customary funeral practices should be employed. Bodies should be buried if acceptable to the community. Health considerations provide no justification for cremation; however, if cremation is the culturally preferred funeral procedure it should be facilitated, if practicable. In some instances sufficient fuel may not be available for cremation. Material needs such as cloth for shrouds should be met.
Before burial or cremation, bodies must be identified and, if possible, the cause of death recorded. This process is of particular importance for disease control, registration, and tracing. Local government officials may also insist on the issuance of death certificates. If the whereabouts of relatives are known, the most immediate relation should be notified.
Consideration should also be given to the need to relocate bodies from burial sites after the emergency situation is over and the DPs are able to return to their homes. This may require further involvement with the local government. A burial location map should be kept from the start of the emergency to aid in locating bodies for removal.