|Food and Nutrition Bulletin Volume 09, Number 4, 1987 (UNU Food and Nutrition Bulletin, 1987, 88 pages)|
|Nutrition and urbanization|
A report sponsored by the World Bank has stated that the frequency and severity of malnutrition in the developing world are increasing more rapidly in urban than in rural areas . Clearly, a major problem exists, but its real extent is apparent only if one considers that urbanization, as the major new factor in the demographic growth of the developing countries, is itself expanding and accelerating. It has already reached dramatic proportions in some countries and is likely to do so in others.
The increasing interest manifested during the last few years in the problems of urbanization should not be interpreted as an attempt to shift attention away from the rural areas, where the problems are still tremendous, to the cities, which, globally considered, enjoy a relatively privileged situation. Rather, it is the response to a recognized need to emphasize the dimensions of the urbanization phenomenon, the profound heterogeneity of the city, and the inequitable and discriminatory treatment applied to certain population groups in urban areas. It should also suggest that the rural and the urban are interrelated elements of the same universe and should be looked at in this wider context. It is therefore not surprising that the FAO (Food and Agriculture Organization of the United Nations) devoted 10 of the 39 pages of its report to its Council in November 1984  to discussing, under the title "Urbanization a growing challenge to agriculture in developing countries," a variety of problems relating urbanization to agriculture, some of which, incidentally, have clear health implications.
At least five reasons justify increasing attention to the health effects of urbanization and suggest that remedial actions must be considered with urgency . The first is that urbanization has become in speed and size a severe problem everywhere. The second is that, in spite of this universality, urbanization primarily affects the developing countries. Third, it is not a temporary phenomenon and no longer depends on rural-urban migration, as two-thirds of urban growth is now the result of natural increase 14]. Fourth, it is no longer confined to capitals: secondary and tertiary cities have started growing rapidly and are not exempt from the problems that affect the bigger cities. Finally, contrary to what happened in the past in the industrialized world, urbanization in the developing countries is primarily the result of rejection of the rural areas. Therefore it is a negative phenomenon that has caught the cities totally unprepared. The consequence is an invasion of squatters and the establishment of populations that by most measurements can be classified as poor.
Facts and figures
As is known from UN statistics , by the year 2000 the world's population will grow by 41%, from 4.4 billion to 6.2 billion people, about half of whom will be living in urban areas. Thus, the urban population will rise 78%, from 1.8 billion to 3.2 billion people, of whom about 2 billion will be living in develop
As the urban growth rate is increasing, the rural growth rate is decreasing; it is projected that by the year 2010 the aggregate rural population in developing countries will decrease in absolute terms (fig. 1). While, between 1975 and 1980, 55% of all population increase was urban, this figure will climb to 83% by the year 2000.
There is considerable variation among countries and regions in the extent and speed of urbanization, but no developing nation can afford to ignore the phenomenon. Where the rate of urban growth is high, as in sub-Saharan Africa and parts of Asia, the repercussions can be considerable, even if the level of urbanization is still relatively low, because of the intolerable burden placed on existing facilities and services.
The number of cities with populations of one million or more has increased considerably during the recent past. There were 118 such cities in less-developed regions in 1980, and it is estimated that there will be 284 (65% of the total) by the year 2000. Likewise, of 26 cities with populations of 5 million or more in 1980, 16 were in developing countries. There will be 60 such cities in the year 2000, of which 45 will be in the developing world.
Major hazards of urbanizationDisease
As the urban poor are at the connecting point between underdevelopment and industrialization, their disease patterns reflect the problems of both. Three main groups of diseases have been identified . The first, most directly related to poverty, includes infectious diseases and malnutrition. The second includes cardiovascular, neoplastic, and mental diseases that, together with accidents, are mainly related to the man-made conditions of the urban environment. The third group consists of disorders that are a result of the social instability and insecurity that have become characteristic of life in many urban areas. They include alcoholism, drug addiction, venereal diseases, and the effect of different types of child abuse and other conditions that overlap with those mentioned.
Malnutrition is a problem of special importance because it not only constitutes a separate disease entity per se but aggravates and is aggravated by other diseases, especially infectious diseases. Thus it can be a co-factor of mortality.
Often malnutrition, like other disease problems of the poor, goes unnoticed or is not appreciated to its full extent, especially when (on the erroneous assumption that cities are homogeneous entities) information is provided in the form of aggregated averages for large urban areas or for a whole city. This makes it impossible for the reports provided to political leaders and managers to reflect the intra-urban differences by geographical areas and socio-economic groups that would be essential to understanding the situation and guiding action.
A systemic study of these intra-urban differences in malnutrition, as well as in other health and health related conditions, is long overdue. The Pan American Health Organization, perhaps in collaboration with UNICEF and other agencies, could pursue the initiative undertaken years ago when it published the book Patterns of Urban Health and Health Services in Developing Countries, in which it could bring out and analyse the variability, often extreme, of health and health-related conditions in the cities. As has been pointed out in a recent UNICEF-WHO publication: "A comprehensive and searching review at the national level of the urban health situation and an assessment of resources, real and potential, seems essential for the development of rational and equitable policies on urban health care" .
Where appropriate sampling procedures have been used and a stratified analysis of the information has been made, it has been possible to show, for example, that in slums and squatter areas energy intake is two-thirds to half the city average, vitamin-A intake one-third to half, and anaemia twice as prevalent, and up to 50% of the children may show signs of malnutrition, 10% of them in severe form .
Observations from Abidjan , New Delhi [9, 10], Santiago , Sao Paula , and various other cities are consistent with these estimates. More important, where the information has been disaggregated by socio-economic groups, it has been found that the availability of nutrients was lower for the urban than for the corresponding rural groups (Colombia ) or that there were more severely malnourished children in low-income urban than rural areas (San Jose, Costa Rica , Guatemala City , and San Salvador ). It is worth noting that neither the large intra-urban differences observed in Moroccan cities nor the even worse conditions of the urban slums compared with the rural areas there would have appeared if city-wide averages had been used .
These results of rural-urban comparison may be at variance with what is generally believed. Some possible reasons can be mentioned . Although in South-East Asia and Latin America rural labourers largely depend on their landlords for their food, many rural families, especially in Africa, own small pieces of land on which they can grow part of their food, or from which harvest surpluses are available; this is generally not possible for the poor in the overcrowded cities. On the contrary, in the cities, although salaries are higher, so are costs, with the result that food itself is more expensive and the poor have a smaller proportion of their income available for it. The Moroccan experience, mentioned above, is a good example of the fallacy of assuming the same relationship between food availability and income when environmental and social conditions are very different.
Furthermore, in the highly competitive situations of the city, women are often forced to work in full- or part-time jobs (generally in the informal sector) to supplement the family income or as the only family support. Under such circumstances, women may typically have less time for food preparation. In addition, they may resort to early weaning, leave their infants in the custody of young children unable to prepare weaning food properly, dilute and divide a limited milk supply among many children, fall easy prey to advertising (causing "commerciogenic'' malnutrition ), or become victims of various combinations of all these factors.
Other examples are available. In Abidjan, while on the whole the availability of food is considered satisfactory, there are striking inequalities between socio economic groups and geographical areas, resulting in worse use of food by certain urban groups than in the rural areas . In the lower occupational strata of San Jose, Costa Rica , as well as of San Salvador, El Salvador , and Guatemala City , the prevalence of second- and third-degree protein-calorie malnutrition was similar to or even slightly above that in rural groups. In Hyderabad a greater proportion of children one to seven years of age were found to have nutritional deficiencies than their rural counterparts . In certain sections of Jakarta, infant mortality is 85 to 90 per 1,000, and the calorie deficiency malnutrition is worse than in rural areas . In the Egyptian national nutrition survey of 1978, the prevalence of stunting was 15.7% and 18.8% in the disadvantaged areas of Alexandria and Cairo-Giza respectively, compared with 27% in villages of upper Egypt and only 1.1% in a comparison group of socio-economically advantaged children . In four slum areas of Bangkok the prevalence of protein-calorie malnutrition was attributed to failure to breast-feed, early weaning, or inadequate artificial feeding . This is in contrast with the rural areas, where almost all infants are adequately breast-fed and rarely found to have severe protein-calorie malnutrition up to the age of six months . Similar observations were made in Chile  and Port Moresby, Papua New Guinea .
Equity in health care: Problems and actions
In spite of the well-known greater concentration of health facilities in the cities than in rural areas and the relative proximity of hospitals and other medical facilities, standards of health care fall far below reasonable minimum levels for those who live in the slums and shanty towns of the developing world. Lack of care is far graver than each city's overall mortality and morbidity data suggest, for these data are, as already mentioned, averages, and conceal the large differences between the best figures and the worst. Some have spoken of an "inverse care law" whereby those in greatest need of medical care have the poorest access to it [26, 27]. Paradoxically, while there is some awareness of the health and health-service problems of rural poverty in the developing world, far less attention is paid to the increasingly important problems of urban poverty.
City administrations can hardly keep pace with the scale and tempo of urbanization and the multiplicity of problems that go with it. Health and other social services already existing in the city are not equitably distributed, nor are they planned, designed, or implemented to help those who are in greatest need. Yet poorer people contribute to the cost of these services through various forms of direct and indirect taxation and through a variety of additional costs imposed on them by the location and operation of the services concerned.
The essence of primary health care
Primary health care concepts apply to urban health systems just as they do to the health systems of whole countries, for the discrepancy between the allocation of resources and health needs is equally striking in the cities, and the gaps between rich and poor, and between need and provision, are actually widening.
The concept of primary health care represents a qualitative jump over the old concept of basic health services. It includes, first of all, a philosophy emphasizing equity and justice in matters related to health. Second, it delineates a strategy that starts from an improved understanding of health problems at their roots (which often lie in the political, economic, and social realities of each nation) and attempts to find solutions that go beyond the technological treatment of problems to their fundamental causes. Thus the strategy also entails political decisions on matters such as employment and income, land distribution and tenure, basic education and housing; co-ordinated efforts by all the sectors concerned with socio-economic development; and a better balance between ''top-down" planning and the upward expression of needs, aspirations, and possible contributions by individuals and communities to their own development. Finally, public health care concepts emphasize actions at the primary level, that is, the level of first contact between the people and the system, particularly in relation to the eight tasks proposed in the Alma Ata Declaration (education concerning prevailing health problems and the methods of preventing and controlling them; promotion of food supply and proper nutrition; an adequate supply of safe water and basic sanitation; maternal and child health care, including family planning; immunization against the major infectious diseases; prevention and control of locally endemic diseases; appropriate treatment of common diseases and injuries; and provision of essential drugs), with the rest of the system being responsive and supportive to action at the primary level and being conditioned by it . Total coverage is the essential target.
This strategy has been endorsed at the highest political level by practically all the countries of the world, which have agreed to report on how their existing medical services are being gradually converted, following that strategy, into health systems with the characteristics of equity, social orientation, and efficiency that should be at the foundation of modern medicine. Indeed, we should be proud of these accomplishments because, as a profession, we now know where we came from and where we want to go, and, remarkably enough, we also know how to get there. Not improperly, somebody has called it a "revolution in medicine," and Dennis elegantly defined it as a "renaissance in community health'' .
Without exception, too little emphasis is given to the application of primary health care principles in the cities, and particularly to the needs of the urban poor. Nevertheless, attitudes are changing, even if only very slowly. In addition to recognizing explicitly the needs of those living in marginal areas, serveral cities have initiated actions specifically incorporating these principles.
To start with, awareness is improving. Advocacy activities have been carried out in Ecuador, Colombia, Peru, Bangladesh, India, Indonesia, and other countries. Some of the cities that have participated in meetings sponsored by UNICEF and WHO within countries or at an inter-country level are using the momentum created by these activities to advance their programmes and change the attitude of "benign neglect" toward the urban poor that has long been common in many countries.
It is as yet most unusual for countries to have a national strategy for urban health that incorporates concepts of primary health care. Yet is is important that such a strategy should be formulated and that it should recognize the exceptional needs of those living in marginal urban areas so as to raise the national awareness of a major urgent human need (giving leverage in the competition for scarce resources!, gain a joint commitment among agencies where this is essential for implementation, and stop inappropriate policies that do not take these needs into account. Several countries, such as Brazil, Colombia, Ecuador, Indonesia, Mexico, Pakistan, and Peru, have formulated, or are moving in the direction of developing, such a national strategy, which will provide for increased investment in favour of the urban poor and will upgrade slums and shanty areas instead of promoting massive relocation.
At the city level there are also few examples of a systematic managerial process tackling the problems of urban deprivation, or of a truly comprehensive city health plan. While short-term and long-term plans sometimes reach out to vulnerable groups, they seldom encompass all the relevant needs, resources, and actions.
Nevertheless, cities such as Addis Ababa, Bombay, Mexico City, and Manila are moving in the right direction, and other important providers (such as hospitals outside the direct control of the department concerned, other city services, social security agencies, and voluntary organizations) tend to be involved in and committed to the plans.
In certain cities, such as Mexico City, however, the present economic recession has jeopardized large scale implementation of existing plans. Also, plans are generally written in conventional terms, such as providing additional medical facilities, or increasing ratios of health care personnel to population; it is rare for them to give the required priority to the items that will actually have the greatest impact on health, such as water supply, sanitation, housing, and nutrition. So long as resources are as scarce as they currently seem to be in these cities, managers are going to have to achieve the difficult and radical feat of reallocating them and reshaping services.
Legislation affecting health is everywhere voluminous, but it can inhibit the improvement of health and living conditions for the urban poor, for example, by prescribing unrealistically high standards for housing or unrealistically low housing densities. Often these standards were initially established for restricted elites, according to criteria that are not appropriate to the slums of the big cities of the developing world . There are, however, a few instances in which laws and regulations do now discriminate in favour of the poor.
For example, in Colombo, Sri Lanka, shanty dwellers are encouraged to improve their shelters through exemption from the urban development authority and zoning regulations, being granted tenurial security for a 40-year lease and allowed a minimum plot size of 37 to 50 m² (instead of 150 m²). In addition, acquisition of the right to hold a lease makes people eligible for financial assistance through a proposed low income shelter loan scheme .
Similarly, in Brazil an interministerial order  prescribes that in poor urban areas agencies should use simplified, effective, low-cost technology in fields such as health care, sanitation, and technical and administrative services.
Attempts to tackle urbanization at the roots or at different stages of the process so as to slow down rural-urban migration or to reverse the trend have met with limited success. Policies, comprehensive health plans, and legislation are necessary but are not enough. They are only as good as the commitment behind them, the ideas in them, and, most of all, the action that follows. At the implementation level most remains to be done.
The redistribution of resources in favour of needy groups and of services at the primary level is the indispensable condition on which the primary health care strategy is based and the proof of its correct implementation. It has not materialized to the extent that would have been desirable, either because of the heavy burden placed on health budgets by the cost of existing tertiary-level facilities or because of the opposition of powerful conservative professional and business groups, or a combination of the two.
The distribution of facilities and the financial and cultural constraints on access to services are such that most marginal groups are patently underserved. Hospitals have traditionally been the main vehicle for delivering medical care to urban populations. However, hospitals are generally removed (physically and socially) from the new urban poor. Moreover, they are already overcrowded, and they emphasize sophisticated technology rather than simple remedies for common conditions. There is a relative scarcity of more peripheral and accessible ambulatory and social services; where they exist, their quality may be so low that people are discouraged from using them. Referral to health services is often difficult for the poor, and the emphasis within services is on curative medicine. Most of the health problems of the urban poor would be more appropriately dealt with by preventive medicine, by relatively straightforward primary health care, and by well-integrated social action, all of which are largely deficient.
On the other hand, it is unrealistic to expect healthy behaviour and compliance with medical advice from a population whose basic needs in terms of employment, shelter, education, food availability, and lifestyle are grossly unsatisfied.
If health administrations are unable to fulfil the essential requirements of the primary health care approach in an equitable and cost-effective manner in the cities, bringing multisectoral action to bear on essential health needs, how likely are they to do so under the much more demanding conditions of rural areas? Yet the organization and functioning of health programmes in many urban areas in fact leave much to be desired. A variety of ministries, social security organizations, municipal health departments, quasi governmental organizations, and private-sector institutions all participate. All these sources of action and elements of power, far from constituting a well-organized and synergistic network, conflict with one another, duplicate action and leave gaps, struggle for funds and power, and produce an irrational and inefficient distribution of services. The indefensible result is high costs, dissatisfaction among clients and providers, and inability to cope effectively with needs and demand.
Neighbourhood health programmed
In spite of this, truly innovative initiatives have been undertaken in three fundamental areas: (1) the decentralization, expansion, and strengthening of infrastructure and services; (2) the integration into the health development process of health-promotion activities that fall under the responsibility of other sectors (so-called multisectoral action); and (3) the mobilization and involvement of communities. Examples are to be found in the cities of many developing countries in different regions of the world [3, 6, 33, 34, 35].
An interesting, popular, and probably the most important example of intervention where two or all the initiatives mentioned above are combined is the neighbourhood health programme. This approach is the urban equivalent of the district-level primary health care complex promoted by WHO for rural areas. It not only reduces the areas and the population to be cared for to manageable proportions but also makes sure that the activities undertaken truly reflect the priorities perceived by the communities concerned to integrate intervention appropriately to increase efficiency, to make referral systems and logistic and managerial support function more effectively, to be less vulnerable to possible political and managerial changes at the national level, and to achieve a more effective intersectoral articulation.
The neighbourhood health programme is becoming a popular technical device in applying public health care strategy to urban areas. It has no established blueprint, since the fundamental characteristic should be to adjust to local conditions. Different models exist in different cities, and more are being developed. Sometimes an approach successfully initiated in the countryside, and based on family spirit and solidarity, has later been adapted to specific urban settings, as in the barrio, kebele, and kampung community health development schemes of Call, Addis Ababa, and Jakarta.
Others were originally formulated as urban schemes; the barangay development programme of Manila is a good example. Its main features, which are common to other similar programmes, include close knowledge of the community, prevention and care of malnutrition, vaccination, treatment of easily recognizable diseases, systems of referral, environmental improvement, and information and education for the families concerned. The programme is based in the community health centre, the upgrading of which is continuously pursued. It emphasizes the training and wide deployment of community health workers and the education of the public by all available means.
In the beginning, neighbourhood health programmes have mostly limited coverage. Their importance lies in their ability to point the way along which development should take place. Three stages can generally be recognized in the evolution of successful programmes: (1) test or demonstration, (2) expansion and consolidation, and (3) institutionalization. This process of "going full scale" is meant to bring a limited operation up to a level at which it can maintain continuity and work toward total coverage and long-term effects.
In practice, too often we see projects that would be judged successful by local criteria remain confined for years to the areas and populations where they were initially started. This may be due to various factors: the resource inputs of the initial effort may have been unrealistic in quantity or quality to allow wider replication; there may have been difficulty adapting to the variety of local situations and to the cultural context; the responsible persons may not have had the same appeal and initiative as those who started the project; the involvement of governments or communities may have been insufficient. These and other reasons were analysed and discussed in a consultation jointly sponsored by UNICEF and WHO in Guayaquil, Ecuador, in October 1984 .
It is important to emphasize that, even under the most favourable conditions, going full scale will not be automatic. The possibility and feasibility of later expansion and replication must be built into the project from the beginning, and the process must be allowed to run naturally and sometimes slowly.
Ultimately, scaling up is a political decision that may involve changing the balance of power within the health system in a way that is better suited to the size and the tempo of urbanization and the health problems related to them. All this requires imagination, hard work, and the ability to be constructively critical and inquisitive, and to put oneself and what is being done continuously in question in the pragmatic search for the most appropriate alternatives. It also requires initiative and resourcefulness, qualities with which urban communities have proved to be largely endowed, as is being recognized increasingly by politicians and managers.
Nutrition interventions are often included in neighbourhood health programmes and are integrated among themselves and with other types of interventions having to do with health services development, water, and sanitation, and family planning. All these contribute, directly or indirectly, to nutritional wellbeing, and may influence each other.
Many types of neighbourhood health programmes have been tried in various countries. They respond to local priorities and include patterns of activities related to these priorities. They use quickly trained, community-based personnel, the community health workers (or those known by other equivalent designations), who constitute the link between the existing health infrastructure and the community and extend into the community some of the activities of the health units. In the urban areas they are primarily concerned with promotion, prevention, and community mobilization. Where the health infrastructure is deficient and fully trained personnel are scarce, they are the only means to involve communities in the health-development process.
There are essentially two types of community health workers: one is selected by the community and is an unpaid, part-time volunteer; the other is recruited and paid by the government, is a full-time worker, and constitutes the first-line government representative in the community. Some neighbourhood health programmes start on the initiative of governments, others on that of non-governmental organizations (NGOs) or international organizations, from which they receive support. The NGOs have been promoters and an important positive influence on urban development in the developing world by enhancing individual and community resourcefulness, and by promoting self-help and achieving self-reliance and a better quality of life. As they are very close to people, especially the poorest, NGOs are good advocates of their needs. They have been said to be the "pace setter, the innovators, the leading edge of development forces at the grass-roots level, which is where it matters" .
The interaction of NGOs with other organizations and with governments is not always easy. Sometimes NGOs are not prepared to be identified with certain government policies and may be reluctant to be partners in a joint effort with other organizations. At the same time, governments are not always willing to accept the participation of NGOs in planning and carrying out health programmes. At the technical discussions of the World Health Assembly in 1985 it was pointed out that "the establishment of an operational partnership between governments and NGOs is overdue and indispensable" . It is from this partnership, in fact, that the best results are likely to emerge.
Hospitals and the referral system
The concentration of curative facilities in urban areas diverts resources from the preventive services that are so crucial for the health problems of the urban poor. In most countries and cities, hospitals consume an extremely high proportion of the total health budget (as much as 80% in some cases). But in too many instances hospitals have too little commitment to or interest in public health care, and play a very limited role in helping to develop strategies and plans for such care in the city. Halfdan Mahler, the Director-General of WHO, has noted: ''A health system based on PHC cannot, and I repeat, cannot be realized, cannot be developed, cannot function and simply cannot exist without a network of hospitals with responsibilities for supporting PHC; promoting community health development action and continuing education of all categories of health personnel; and research" [38, 39].
The conclusions of the WHO/Aga Kahn Foundation Conference pointed to a new and important role for the hospital in public health care, for which prerequisite conditions are unambiguous support by political leaders and appropriate guidance for co-ordinating mechanisms established by national governments at each administrative level. This structure should include a committee, council, or board made up of representatives from each part of the health system (hospitals, health centres, and primary care workers) as well as representatives of the community, who meet together to deal with questions concerning policies, management, and resources. Every hospital should be associated with a well-defined catchment area within a regionalized framework, and should have a department of community health to mobilize interest, develop expertise, and interact on the one side with other health personnel inside and outside the hospital and on the other with the community in its catchment area.
The responsibilities of these departments of community health should include support and encouragement to primary health care in the hospital's catchment area; in-service training to reorient hospital workers so as to change their ''hospital" outlook to a "health" outlook; co-operation in the education and supervision of primary health care workers in the field, including helping to improve management and administration; collaboration with the community in seeking relevant information on health problems and appropriate solutions; making sure that the hospital meets its referral and logistic support responsibilities; development of effective ways in which the community can assist in improving hospital services; work with other public agencies, NGOs, and community associations (including women's groups) active in the catchment area; identification of gaps in the primary health care services and introduction of appropriate innovations; and stimulation and conduct of relevant health services research that focuses on practical issues to achieve progressive improvement of services.
Reorientation of the hospitals should facilitate and proceed in parallel with reorganization of the referral system within the city and redistribution of the patient workload, to allow a more efficient and coordinated use of all health facilities and to offer better access to users.
Such a bold reorganization was successfully attempted in Cali, Colombia , in response to a continuously deteriorating situation of overcrowding and improper use of central hospital facilities and bypassing and underuse of peripheral health units. This project particularly benefited poor populations living in peripheral barrios. In fact, one of its main achievements was to strengthen peripheral facilities, thus removing the main obstacle to their correct use and the main reason for hospital congestion. By influencing the public through the planned involvement of the mass media, religious and other organizations, and the schools, by including the home as the basic unit of service provision, and by informing health professionals and medical students, awareness of the urban health system was improved; people were guided toward self-help or the appropriate use of health facilities; and feedback was encouraged. At the same time, supportive supervision of the peripheral clinics and the logistic system supplying them were revitalized.
Environmental conditions and services
Closely related to the health problems of the urban poor, namely, infectious diseases and malnutrition, are the environmental conditions in which these people live.
The high population density of slums and shanty areas places an intolerable burden on the urban infrastructure and physical environment. Among the resulting problems, the worst are those related to water supply (quantity and quality) and sewage disposal. They influence each other, and their frequent absence or unsatisfactory handling provides the most striking evidence of the neglect with which the urban poor are treated in many cities. As I have pointed out on a previous occasion, "No amount of statistics or reports can convey the true feeling and the real dimension of the destitution, and even abjectness, under which large population groups in many cities of the world are forced to live. Only exposure to that destitution and direct observation of it can create the awareness and motivation required for dedicated involvement" .
Water and sanitation are very closely related in the sense that improvements in one may provide little benefit in terms of disease prevalence without corresponding improvements in the other. Moreover, the quantity of water is an important prerequisite for the removal of the sewage, and precarious conditions of the sewage system may well lead to contamination of the water. Vice versa, a water supply without a waste-water disposal system leaves stagnant pools of domestic wastes, where mosquitos may breed, and where animals will bathe and children play. Teller  says that it is on the development of these services that the success or failure of preventive work in poor urban areas largely depends.
In rural areas the need for water supply is greater than for improved sanitation. In urban areas, because of lack of space and high population densities, both are extremely important. Yet governments and private landlords are reluctant to invest in areas that they consider to be illegally occupied and that are scheduled to be cleared, sooner or later, supposedly with a view to more productive uses. So the paradox of ''permanent temporariness" is created. The situation is aggravated by the tendency to consider only high-cost conventional solutions to the problems of the slums and to refuse alternative, decentralized methods that cost less and may still be effective, provided that they have the support of those who live there and that the physical measures are accompanied by behavioural changes.
The people themselves may add to the problem. Their perception of priorities will be influenced by the immediacy of their needs and the visibility of the results. For a mother with a sick child, for example, medical treatment and the money to pay for it are what really count at the moment. Or people may be unconcerned with cost and maintenance, and adopt the attitude that "it's the government's duty to collect the garbage" . Worse, they can, for instance, break into a water supply system to establish illegal connections and, in doing so, contribute to the deterioration of the equipment and leakage, waste, and possibly the contamination of the water.
Population densities are very important, not only in terms of the numbers of people to be served but also because they may influence the choice of systems. Densities are often extremely high: In the old city of Kabul in 1975 the housing conditions of 37% of the 541,000 inhabitants were such that more than two families had to live in one unit and two to three persons in one room. In Old Delhi there can be as many as 270,000 people per km² . In the medina of Casablanca the average density is 70,000 per km² (ten times as many as in upper-income residential areas). In the three cities of Ghana with more than 50,000 people, 35% of the population lives 20 and more to a house. And three-quarters of Bombay's families live in one room or share a room with another family .
Drinking water is particularly critical, and the availability of a piped system does not by itself ensure the expected supply: relative scarcity in relation to the numbers to be served, low pressure, and intermittent delivery may make the service very unsatisfactory. Numerous supply methods are generally available. In the Klong Toey settlement of Bangkok (population 30,000), for example, 55% of the dwelling units purchase water from vendors; 30% get their water from neighbours who have running water from the city main; 3% have outdoor connections to the city main; 10% use running water from a nearby tap; 1 % use rain water; and 1 % use other sources . In a Seoul squatter settlement, water may be supplied at public water taps only in the middle of the night, when demand is low in more privileged sections of the city .
Similarly, several methods are used to dispose of human waste. The most common are defecation trenching grounds (not practical in most cities because of limited space), "wrap and carry" (where there are places for dumping close by), overhung latrines (above tidal flats, weirs, canals, or beaches; but serious problems arise where the water is stagnating and is used for domestic purposes), and wet and dry pit latrines (quite common but difficult to maintain and highly contaminating).
Equally inadequate are methods of garbage disposal. To qualify theoretically for municipal collection, as in long-established slums, does not guarantee removal; in this case the alternative is the street. Many squatter settlements, as in the slums of Guayaquil, are built in the vicinity of or above garbage dumps. Everywhere a large informal industry (called by the Japanese the "regenerated resources industry") develops, involving a variety of rag-pickers, rag-buyers, rag-dealers, and processors. The health risks of all these situations are obvious.
Governments and international organizations involved in improving water-supply and sanitation systems usually give priority to rural projects, because the majority of people in most developing countries live in rural areas, and because this may help to slow down rural-urban migration. The numbers and conditions of people living in slums and shanty towns in developing countries also call for immediate attention, not only because of epidemiological and technical considerations but also for humanitarian reasons. The fact that one-third of the 1979 investment of the World Bank in water and sanitation was directed to relieving urban poverty, using the "site-and service" or "slum upgrading'' approach, supports this conclusion. Unfortunately, such new investment often cannot keep pace with deteriorating conditions, and sometimes speculation and manipulation prevent the improvements from benefiting those for whom they were originally intended .
The use of traditional practices and practitioners is not limited to rural areas. To a lesser extent it is also observed in urban areas, but there seem to be differences within the population - for example, between immigrants of the first and second generations. The urban Health Sector Assessment of Cairo emphasized that clients may use a variety of health care facilities and depend on self-care, the formal system, and the informal system . About 22% of the population studied delivered their babies at home, assisted by a traditional birth attendant. A similar pattern is observed in the cities of India, Indonesia, and other countries, whether or not the birth attendants have been trained.
In Indian cities modern and traditional systems of medicine coexist . The trend is believed to be toward an increasing adoption of modern scientific therapy, but the number of traditional practitioners does not seem to diminish, although their use in the cities is decreasing compared to the rural areas. With some exceptions, their practice appears to be limited primarily to certain ailments, particularly joint and muscle pain, and their services are generally not sought for serious diseases.
Little is known about the way the two systems operate side by side in the same metropolitan setting. A survey indicated that all systems of medicine seem to provide fairly satisfactory solutions for common ailments; the prestige of many traditional practitioners is still high, and their services seem to cut across all social classes. Indigenous medical practitioners are considered to represent a vast under-used resource outside the official health services, but collaboration between the two systems has hardly begun and many obstacles stand in its way.
City health departments
Effective support for primary health care may require the reorganization and strengthening of city and national health departments. More important than organizational change, however, is a change in attitude throughout the departments, since a fundamental shift of values, strategy, and approach is involved. In most cases, reorganization is not the first step required, but rather but rather should evolve when there is already some record of initial achievement. Various alternatives were discussed in a recent WHO document . On the whole it seems better not to set up new public health care units vertically organized, but to build them into the plans and operating systems that shape activity across the entire department. Collaboration and communication depend fundamentally on personal qualities and personal contacts. They also depend on there being a sufficient congruence of objectives among all those concerned.
Such reorganization is now in progress at the Municipal Health Department of Manila . It consists of several steps, including drastically shortened lines of communication between the department and its operating staff in the field; new roles for the public health nurses expected to work more closely with community leaders; coordination of field services under the supervision of a team leader; strengthening of the city information system and its ability to assess needs dynamically, to monitor progress, and to evaluate the effect of health interventions; improved training programmes for the basic and continuing education of community health workers; and, finally, greater involvement in meeting the basic needs of the client population (food, water, sanitation, housing, employment) through intersectoral collaboration.