Reproduced, with permission, from:
World Resources Institute. 1992. Population and human development. Chapter 6 in World Resources 1992-1993: A guide to the global environment--toward sustainable development. Oxford, England: Oxford University Press.
The 1.7 billion children under age 15 who inhabit the earth today represent one third (32 percent) of the planet's population; 82 percent of these children (1.4 billion) live in the developing world. Moreover, during the 1990s, the largest generation ever will be born, with nearly 90 percent of the expected 1.5 billion births to occur in developing countries (40). These are the same countries in which large numbers of children still die needlessly from malnutrition and disease caused by inadequate drinking water. poor sanitation, and other environmental ills. Nearly all deaths of children under age 5 (97 percent) and maternal deaths (99 percent) are in developing countries (41) (42) (43).
The environmental conditions in which these children live pose a serious threat to their current health and future prospects (44) (45). As the most fragile members of society, they are most vulnerable to disease and environmental stress; their long-term well-being depends on the sustained ability of the Earth's resources to support this still expanding population.
At a rhetorical level, recognition is growing that societies have responsibilities not only to their current citizens, but to future ones as well. At the World Summit for Children, held at the United Nations in September 1990, leaders from 71 countries committed themselves to "promoting the survival, protection, and development of the present generation of children and all generations to come" (46). For those concerned about sustainable development, the concept of "intergenerational equity" suggests that the welfare of future generations--including the children already born--should be an implicit consideration in today's decisionmaking (47). Despite the rhetoric, however, the economic, social, and environmental conditions in which many children live put them at serious risk for ill health, malnutrition, life-long disability (both physical and mental), and early death.
Progress has been made. Worldwide, the annual number of deaths of children under 5 declined by 4.7 million between 1965-70 and 1985-90. Developing countries have improved their children's health considerably. Between 1965-70 and 1985-90, the infant mortality rate declined by 33 percent in developing countries, from 116 per 1,000 live births to 78. (See Table 6.3.) The mortality rate of children under 5 years of age shows a similar trend: a 35 percent reduction, from 184 to 119 deaths per 1,000. Under-five mortality in industrialized countries during this time period dropped 47 percent, but the number of deaths per 1,000 was already far lower, dropping from 32 to 17. (See Table 6.2.) In the developing world, 37 percent of total deaths are children under 7; in the developed, 3 percent (48) (49). A baby born in a developing country today is seven times more likely to die before its first birthday than one born in the industrialized countries. Among developing countries, disparities in child mortality have widened; in the early 1960s, the differences between the best and worst rates were 7 to 1; by the early 1980s, they had increased to 15 to 1 (50). Unfortunately, recent reports show that progress in children's health has slipped in the United States. (See Box 6.1.)
MAJOR CAUSES OF DEATH IN CHILDREN
In the developing world, 12.9 million children under age 5--more than 35,000 a day--died in 1990 of diseases, most of which were once as common in developed countries (51). In other words, these children are dying of diseases for which effective means of prevention, as well as effective treatments, are available. (See Figure 6.5.)
Acute Respiratory Infection
Respiratory infections are responsible for some 4.3 million childhood deaths annually. About 17 percent of these deaths are a consequence of pertussis (whooping cough) and measles and are thus preventable through immunization; the vast majority--roughly 75 percent--are caused by pneumonia (52).
In the developed world, most children recover from pneumonia; in developing countries, they often do not. In Guatemala, the mortality rate among infants due to influenza and pneumonia is estimated to be 1,000 per 100,000 live births; this is 8 times higher than Argentina (120 per 100,000), 10 times higher than Cuba (97 per 100,000), and 125 times higher than Canada (8 per 100,000) (53).
One important contributing cause to acute respiratory infections (as well as to other diseases) in children are the particulates released when wood and animal dung are used to fuel traditional stoves. (See Chapter 13, "Atmosphere and Climate.") WHO estimates that 400-500 million people (including many women and young children) are affected worldwide, with rural homes having levels of particulate pollution ranging from 300 to 14,000 micrograms per cubic meter. The WHO maximum recommended level is 100-150 micrograms (54)
Bacterial pneumonia occurs far more frequently in developing countries than viral pneumonia (representing two thirds to three quarters of pneumonia cases), making oral antibiotics the treatment of choice (55). Because their administration has been considered the preserve of medical doctors, antibiotics have been difficult to dispense widely in developing countries. But as a result of a series of pilot studies, WHO estimates that deaths from acute respiratory infections can be reduced by at least 30 percent if community health workers are trained in a standard protocol that involves dispensing antibiotics when certain clear indicators are present (56) (57) (58). There already is some evidence of improvement; WHO estimated that respiratory infections claimed 4.3 million children in 1990, down about 10 percent from the 1985 estimate of 4.8 million (59).
Diarrhea
In almost every developing country, diarrhea and respiratory infection are the first and second most common causes of illness and death among children under 5 years old (60). Diarrheal disease causes about 3.2 million child deaths annually (61). In some countries, children suffer an average of eight or nine diarrheal episodes a year (compared with a global average of three per child per year) (62). As much as 13 percent of a child's life may be spent ill with diarrhea. Repeated and prolonged bouts contribute to undernourishment, which in turn increases the severity and duration of future diarrheal episodes (63).
The most serious aspect of diarrhea is the dehydration that usually accompanies it--a condition that can be prevented if parents and health care workers have access to, and know how to use, oral rehydration therapy (64). In this simple technique, vital fluids and ions lost during diarrheal episodes are restored through the administration of either a prepared packet of oral rehydration salts (ORS) or a home-prepared solution. Oral rehydration has been called one of the most important medical breakthroughs of the century in terms of numbers of lives affected, providing a less expensive and more accessible means of treatment than intravenous rehydration (65). Promoted by WHO since 1978, oral rehydration is now theoretically accessible to about 60 percent of the children in developing countries, but is actually used to treat about 30 percent of the children who contract diarrhea. According to UNICEF, this treatment saves an estimated 1 million young lives a year (66) (67).
Because it is important for children to continue to receive nutrients during diarrheal episodes, oral rehydration therapy is increasingly considered to involve both the administration of fluids and continued feeding. Ongoing research suggests that cereal-based oral rehydration therapy, although still somewhat controversial, may have the potential to be more effective than the standard ORS solution, which prevents dehydration, but does not actually prevent diarrhea nor reduce its duration or amount. Cereal-based therapy can reduce fluid losses by 30-50 percent as well as shorten the duration of diarrheal episodes (68).
Even more important than treatment of diarrhea, however, is its prevention. Most diarrhea is caused by bacterial, viral, and parasitic infestations transmitted through water, food, and contact with fecal matter. Preventing diarrhea requires better sanitation and more abundant, cleaner water supplies, as well as health education aimed at promoting breastfeeding, immunization, improved personal hygiene and food handling practices, and the penning of farm animals such as chickens and cattle (69) (70). Exclusive breastfeeding in the first six months of a child's life, for example, can dramatically reduce the incidence of diarrhea; the addition of even water or tea to the infant's diet has been found to double or sometimes triple the likelihood of diarrhea (71).
Vaccine-Preventable Diseases
At the end of the 1970s, the international community made a major commitment to immunizing the world's children against six major childhood diseases--measles, diphtheria, pertussis, tetanus, polio, and tuberculosis. This commitment has produced one of the most spectacular public health successes of the past decade. Today, average immunization levels of children in developing countries are at least 80 percent for all vaccine-preventable diseases except measles (78 percent) and neonatal tetanus (which requires the immunization of women, only 38 percent of whom were immunized by 1990) (72). The United Nations Children's Fund (UNICEF) estimates that these successes are preventing at least 2.5 million child deaths each year. All told, more than 12 million lives have been saved and more than 1.5 million cases of polio prevented (73).
Despite this progress, more than 2.1 million children died of vaccine-preventable diseases in 1990 (74). Expanding immunization coverage further will be more difficult, because those not yet reached tend to be from the poorest families, among whom disease and malnutrition are both more common and more likely to be fatal. The international community has committed itself to achieving 90 percent coverage by the year 2000, with a particular emphasis on reducing measles deaths by 95 percent and on eliminating tetanus and polio entirely (75)
Measles and neonatal tetanus are the biggest killers among vaccine-preventable diseases and also those for which immunization lags furthest behind. Measles accounts for some 900,000 deaths a year (76); it also causes malnutrition, further illness, and loss of vitamin A. The incidence of illness and death in the period after a measles outbreak can be 10 times greater among children who had the disease than among those who did not (77). Immunization against measles can have a significant effect on child mortality, helping to reduce deaths from all causes. In Bangladesh, for example, children who were vaccinated against measles experienced at least 40 percent lower mortality than those who were not (78).
Neonatal tetanus could be eliminated if all pregnant women were immunized and delivered their babies under hygienic conditions. Tetanus currently kills some 560,000 newborns each year and an estimated 15,000-30,000 mothers; it is an excellent barometer of the health status and well-being of mothers and newborns (79) (80) (81).
The eradication of smallpox through immunization in the 1970s provides a telling example of both the possibility and the cost-effectiveness of such efforts--approximately $1 billion a year is saved in vaccine and surveillance costs (82). Another success story is the near-total eradication of polio from the Americas. In 1985, bilateral, multilateral, and private voluntary agencies joined with the Pan American Health Organization in an intensive campaign to rid the hemisphere of polio. The campaign involved high immunization levels, enhanced surveillance to document and investigate each case, and measures to stop transmission whenever a new case occurred. In 1990, there were 18 new cases, compared with 1,050 in 1986; as of July 1991, there were only 3 confirmed cases for the year. Complete eradication is anticipated in the near future (83).
Malaria
Approximately 40 percent of the world's population is at risk of malaria, which occurs in more than 100 countries (84). It is most endemic in sub-Saharan Africa, where often more than 50 percent of the population in rural areas is infected (85). Because of widespread underreporting, the exact number of deaths due to malaria is unknown but is estimated to be about 1 million annually (86), mostly in sub-Saharan Africa and mostly in the younger age groups (an estimated 800,000 children under 5 die from malaria each year) (87). Those children who survive may acquire immunity against the most severe manifestations of the infection, but often the remnants of the disease adversely affect their growth, physical fitness, and educational achievement (88).
Environmental conditions contributing to the spread of malaria include stagnant waters around homes and construction sites; irrigation projects; industrial, hydroelectric projects requiring impoundment of water; changes in ecosystems caused by widespread deforestation, soil erosion, and flooding; overcrowding and unsanitary living conditions. Overuse of pesticides increases the mosquito's resistance and further aggravates the problem.
Combatting the disease requires controlling the mosquito population through appropriate use of chemical or biological means, preventing mortality through case management, and implementing a range of environmental management techniques depending on the predominant vector species. Malaria is transmitted through a complex of technical, political, social, cultural, environmental, and economic factors; to be successful, measures to reduce malaria mortality must be locally and regionally specific. Simple administration of even a very effective drug such as chloroquinine is not enough to combat the disease; when used in the absence of an effective primary health care system, chloroquinine has in fact contributed to the resurgence of malaria by increasing parasite resistance. (See World Resources 1990-91, p. 58.) Nevertheless, when used in combination with strategies appropriate to local conditions, the drug can still provide a clinical cure in large areas of the world (89).
A ministerial level meeting to review the global malaria situation and develop new strategies is scheduled for October 1992 in Amsterdam. Organized by the World Health Organization, the meeting is to be preceded by a series of regional meetings in Africa, Asia, and Latin America.
Malnutrition
Although data are incomplete, a 1990 UNICEF survey suggests that more than one third of the developing world's children under 5 years of age (excluding China) are malnourished (90). Of these 150 million children, at least one in six--25 million--is severely malnourished. Most of the world's malnourished children reside in Asia--60 percent (91) excluding China, 80 percent including China (92). In sub-Saharan Africa, the incidence of malnutrition appears to be increasing (93).
How frequently malnutrition is an immediate cause of death is unknown (94). UNICEF, however, estimates that it is a contributing cause in approximately one third of child deaths (95). In Latin America, malnutrition was found to be the underlying or related cause in more than half of all childhood deaths (96).
Malnutrition shows up quickly in young children, acting as an early warning sign of distress, ill health, and famine. The appearance of malnutrition in young children is believed to reflect the health and nutritional situation of all members of the population (97).
Malnutrition can lower a child's immunity, making the child more susceptible to diseases such as diarrhea, measles, and respiratory infections. These in turn reduce appetite, cause nutrient loss, inhibit absorption, and alter the body's metabolism, thereby resulting in inadequate dietary intake and further malnutrition. This vicious cycle of malnutrition and infection has been termed the "most prevalent public health problem in the world today" (98).
Often the cycle begins even earlier when malnourished women give birth to babies with low birth weight (2,500 grams or less). Some 350 million women are estimated to have nutritional anemia (99). These women are more likely to die in childbirth as well as to have babies too small to thrive. Between 12 and 15 percent of all babies in developing countries are born with low birth weight and these babies account for 30-40 percent of all infant deaths (100). Low birth weight babies are seven times more likely than other babies to die of respiratory infections and three times more likely to die of diarrhea (101). In the 1980s, nearly 1 of every 10 babies in Latin America had low birth weight which was a factor in 78 percent of early neonatal deaths (i.e., those deaths that occur in the first week of life) (102). Measures to reduce low birth weight--such as improved nutritional health for women and girls, more food and rest during pregnancy, and increased spacing between births--could significantly reduce infant deaths.
The international community has committed itself to halving the incidence of severe and moderate malnutrition among children by the year 2000. If that target is to be met, parents and community health workers must be given basic nutrition information and trained to monitor children's growth. For example, exclusive breastfeeding for the first few months of life can improve child health significantly. As noted above, it reduces diarrheal morbidity and provides newborns with the best possible nourishment as well as antibodies against common infections. UNICEF estimates breastfeeding could save 1.5 million lives a year. Because breastfeeding acts as a natural contraceptive by inhibiting ovulation, it lowers fertility rates and helps lengthen birth spacing, thus improving the health of both mother and child (103).
Two other widespread nutritional problems--vitamin A and iodine deficiency--require attention. Some 40 million children under 5 suffer from vitamin A deficiency (104). Every year, 250,000 children are permanently blinded by the disease and another 25O,000 have their eyesight partially impaired. At least 100,000 of these die within a few weeks of contracting the disease (105). In addition, lack of vitamin A has been associated with other diseases, including diarrhea and respiratory infection (106) (107). Vitamin A supplementation has been found to reduce measles-associated mortality by up to 50 percent (108) (109).
Improvements in vitamin A status, either through supplementation or dietary changes, are expected to save the sight of 250,000-500,000 children in developing countries each year, and the lives of 1 million children annually (110). In the longer term, adding foods rich in vitamin A such as green leafy vegetables and yellow fruits to diets is the best means of overcoming vitamin A deficiency (111). In fact, it has been argued that supplementation is a diversion of resources from the necessary task of improving diets (112). However, the mounting evidence on the benefits of adequate vitamin A consumption, combined with the difficulties in bringing about dietary changes and the seasonal or general lack of foods rich in vitamin A in many areas, is providing growing support for vitamin A supplementation for children and mothers to alleviate short-term or particularly severe deficiencies (113) (114) (115).
As a result of iodine deficiency disorder (IDD), 200-300 million people are afflicted with goiter, 20 million with mental retardation, and at least 6 million with cretinism. IDD is most prevalent in mountainous regions and flood-prone areas; when iodine is washed from the soil, whole communities may suffer, with children the most affected. Without iodine, they grow up stunted, retarded, apathetic, and incapable of normal development, speech, or hearing. Ensuring that diets include iodized salt or administering iodine in oil either orally or through injection can remedy the deficiency (116).
IMPROVING CHILDREN'S HEALTH
There is no direct measure of a population's general health, well-being, and productive potential. Although mortality figures measure only the extreme outcome of ill-health--death--they also indicate the extent of health problems in a population. Obviously, widespread health problems can affect a country's productivity and development potential.
Both infant and under-five mortality rates are considered to reflect levels of nutrition (especially among pregnant women, infants, and children), education (especially female literacy) (117), general socioeconomic status, and access to health services (118). Of the two measures, the under-five mortality rate is considered a better technical indicator, both because data collection is better and because it is one of the few social indicators for which long-run time series are available.
Reducing child mortality is possible at various levels of national income. It can be achieved through broad social and economic development or through direct targeted interventions--interventions that for a number of reasons are also direct investments in sustainable development.
First, as previously discussed, over the long run, reducing child deaths slows down the rate of population growth. In most countries, this change from high mortality-high fertility to low mortality-low fertility is not evident until under-five mortality rates fall to 150--or even 100--deaths per 1,000 live births. From initial child mortality rates of 300 or more, many countries now have reached this critical point where further declines in child mortality can be expected to be accompanied by steep declines in fertility. Where strong family planning programs exist, the decline in births is likely to take place even more quickly (119). Figure 6.6 shows a strong association between lower child death rates and the use of contraceptive measures in 67 countries for which data on both indicators are available.
Second, the environmental conditions that are both a symptom and a result of underdevelopment cause much of the ill health and disease affecting today's children. Measures that simultaneously address the related issues of poverty, ill health, and environmental degradation include providing adequate water supplies, safe sanitation facilities, and small-scale irrigation (which can increase household food supply and income as well as avoid the negative environmental and health effects of large-scale irrigation).
Third, healthy children who grow into healthy adults are more likely to make productive contributions to their communities and their countries, as well as to pass on positive health practices to the next generation. Sustainable development depends on a productive, healthy, educated population. (See Chapter 1, "Dimensions of Sustainable Development.")
Health and Poverty
A society's overall level of income is not necessarily a good indicator of its children's life chances as measured by infant and child mortality rates. Compare, for example, Sri Lanka and Brazil. At an average annual per capita income of only $430, Sri Lanka has one of the lowest child mortality rates of all developing countries (36 per 1,000). Brazil, with an average annual per capita income five times higher than Sri Lanka's ($2,550), has a child mortality rate twice as large (77 per 1,000). (See Chapter 15, "Basic Economic Indicators," Table 15.1, and Chapter 16, "Population and Human Development," Table 16.3.) With an average annual per capita income of $182, the state of Kerala in India is poorer than India as a whole; yet in 1986, the state had an infant mortality rate of 27 per 1,000, while India's was 86 per 1,000 (120).
As the Human Development Report points out, social programs aimed at improving literacy and health care can have a bigger effect on child mortality than simply increasing GNP. Figures 6.6 and 6.7 show that child mortality is inversely correlated with the use of contraception and with female literacy. There is only a small correlation between GNP and child mortality within developing countries (121). However, in the absence of concentrated health and education programs, poorer children do suffer more health problems than wealthier children. In the poorer Northeast of Brazil, for example, the 1986 infant mortality rate of 116 per 1,000 live births is comparable to many African countries and more than twice that in the rest of Brazil (52 per 1,000) (122). After Sri Lanka changed its food subsidy policies in the late 1970s, the infant mortality rate in 1980 was twice as high among the poorest agricultural workers (100 per 1,000) as it was for the country as a whole (50 per 1,000) (123).
In developed countries as well, it is the poorest segments of society whose children suffer most. In the United States, the Department of Health and Human Services has found that poor children are more likely both to be ill and to have many more risk factors for poor health than children in families with higher incomes. One quarter of all children under age 6 are members of families living below the government-defined poverty level. These children are more likely to suffer from prematurity, low birth weight, birth defects, and infant death. They are twice as likely, between the ages of 1 and 2, to have iron deficiency anemia. They are also at greater risk of growth retardation and impaired mental and physical development, and they experience more sickness from infectious and other debilitating conditions. In 1980, U.S. children from families with incomes under $5,000 had slightly more than nine disability days, compared with four disability days for children from families with incomes of $25,000 or more (124).
In the United Kingdom, a child born to professional parents can expect to live more than five years longer than a child born to parents who perform unskilled manual labor (125). In the Soviet Union, infant mortality rates in 1987 were 19 per 1,000 live births in urban areas and 27 per 1,000 live births in rural areas (126). Such large gaps can be found even within communities. In Guatemala City, 1976 data showed that the mortality rate for children under age 2 was 113 per 1,000 live births for poor illiterate women, compared with 33 per 1,000 live births for middle-class women with secondary education (127).
Water and Sanitation
Universal access to safe drinking water and to sanitary disposal of excreta are two of the major international targets for improving the health and well-being of children. These goals were set during the International Drinking Water Supply and Sanitation Decade of the 1980s and endorsed again at the 1990 World Summit for Children. As of 1990, 81 percent of urban areas and 58 percent of rural areas had access to safe water supplies; 71 percent of urban areas and 48 percent of rural areas had access to sanitation (128).
A 1990 review of 144 community-level studies concluded that when water and sanitation are made available to people, substantial health impacts can be achieved. In particular, the review found that water and sanitation was associated with a median reduction in child mortality of 55 percent. These community studies also suggest that, particularly for diarrheal disease, improvements in excreta disposal and water quantity have even greater health impacts than improvements in water quality (129).
The gains to be made from improving water supplies (both quantity and quality) and sanitation are not automatic, however. Simply installing water taps, pit latrines, hand pumps, and other hardware is not enough; their success depends as well on community participation and changes in behavior (130). Studies have found, for example, that handwashing can reduce the incidence of diarrheal disease by 14-48 percent (131).
The cumulative effect of reducing a number of water and sanitation-related diseases may be significantly greater than the measurement of any one disease would indicate; child mortality, for example, may be reduced more than the incidence of diarrhea (132). Moreover, improvements in water and sanitation may reduce the severity of disease even more than the incidence.
There are also indirect benefits that follow initial improvements. Difficult to quantify, these benefits are nonetheless significant. Well-designed investments in water and sanitation bring socioeconomic, educational, and nutritional benefits. Additionally, by reducing illness they improve productivity and the ability to learn, which in turn increase general well-being, making water and sanitation measures even more cost-effective (133).
The Role of Women
An estimated three quarters of all health care takes place at home, where women--particularly in their role as mothers--generally have responsibility for promoting their families' health and nutrition (134). Much has been learned recently about which factors help or hinder women in improving their children's health.
Women's education is closely related to child health, whether health is measured in terms of infant and child mortality or children's nutritional status (135) (136). Figure 6.7 shows a high correlation between female literacy and child mortality rates. Detailed studies of 28 countries show a nearly consistent inverse relationship between child mortality and mothers' education (137).
Women's education can improve children's health through a variety of mechanisms: increased use of health services and better knowledge of nutrition; more decisionmaking power within the family and the community; and greater earning power. Women with higher levels of education are more likely to plan their families and thus to increase birth spacing, reducing a major mortality risk factor (138).
Increased education of mothers often is associated with higher education levels of fathers, higher levels of household income, the availability of water and sanitation, and the availability of other health inputs--all factors that also tend to be associated with improved child health. The net effect of either mother's or father's education on health is difficult to determine precisely (139) (140). Education of a mother is estimated to be twice as effective as education of a father in lowering infant and child mortality (141). It is not necessarily the content of the education that makes a difference in children's health but the mother's increased access to information, including health information (142).
Lack of education is not the only problem constraining mothers from protecting their children's health. Poor rural women in developing countries often work 60 to 90 hours per week gathering wood, collecting water, growing and cooking food, contributing to the family income, and caring for their children (143). For these women, steps to make immunization more accessible and the administration of oral rehydration therapy easier may be key to their ability to raise healthy children (144).
Health Care
The technologies--such as immunization and oral rehydration therapy--that have made a significant difference in child health depend on a well-informed parent supported by an accessible health worker. The parent, usually the mother, must recognize the initial symptoms in time to provide home care or seek outside assistance. She must also be able to turn to someone who can immunize children, take other steps to prevent illness, and treat children who do fall ill. This person need not be an expensively educated physician; a well-trained health worker, preferably one with roots in the community and opportunities for both further education and support, can handle most situations. Access to such community health workers is essential if the opportunities for significantly reducing child deaths are to be realized.
Almost three quarters of the health expenditures of developing countries are devoted to urban hospitals that provide expensive, Western-style curative care to a minority of the population. UNICEF estimates that reducing this amount to 45 or 50 percent of total government expenditures on health would release enough funds to train the 1 million health workers needed to provide health services to the poorest 1 billion people in the developing world (145).
INDUSTRIALIZATION AND URBANIZATION
Although most environmental causes of poor health in developing-country children are related to poverty and a lack of modern development--lack of water and sanitation, poor housing, indoor air pollution resulting from the burning of wood and dung--some parts of the developing world face health hazards from industrial pollutants and urban development. Aggregate data are scarce, but evidence is mounting that industrialization and urbanization are combining to expose some populations to a variety of toxic chemicals contaminating the air, water, soil, and food. It is an area in which the need for more research and better data gathering is urgent.
Industrial Pollutants
Pollution in whatever form affects children more than adults, and poor children--who are exposed to more kinds and higher levels of pollution--are affected most of all. Children's smaller body weights and developing organs put them at greater risk. So do their habits: infants suck indiscriminately on contaminated objects; older children play on streets filled with car fumes and lead exhaust, on sewage-polluted beaches, or on open spaces that collect hazardous wastes. Malnourished and disease-prone children are even more vulnerable (146).
The fetus is perhaps most vulnerable. Methyl mercury, pesticides, polychlorinated byphenyls (PCBs), carbon monoxide, and such self-administered contaminants as alcohol and tobacco have been shown to have adverse health consequences for exposed fetuses (147). Although no aggregate data exist on the extent of the problem, selected data provide a good indication.
Mercury in seafood ingested by pregnant women has been linked to cerebral palsy in infants. On average, mercury levels in these babies' blood is 47 percent higher than those of their mothers (148). Children whose mothers ate foods contaminated with PCBs have suffered various forms of retarded growth (149). Carbon monoxide, which WHO has found regularly reaches unhealthy levels in many cities, can result in decreases in fetal weight, increases in perinatal mortality, and brain damage, depending on the length of time a pregnant woman was exposed and the concentration in the air. Here, too, the concentration in the fetus generally exceeds that in the mother (150).
Air Pollution
Air pollution--once a problem only in the industrialized world--now affects most large urban centers in developing countries; the number of vehicles, poor vehicle maintenance, industrial growth, the absence of effective air-quality regulations, and the burning of charcoal, wood, and paraffin by growing slum populations for fuel and cooking combine to create some of the dirtiest cities in the world (151) (152). Although environmental improvements there have been remarkable in recent years, the city of Cubatao, Brazil in 1980 reported grim statistics regarding health effects of air pollution. In the industrial city, 40 out of every 1,000 babies were stillborn; another 40, mostly deformed, died in the first week of life. In the same year, with a population of 80,000, Cubatao had some 10,000 medical emergencies involving tuberculosis, pneumonia, bronchitis, emphysema, asthma, and other nose and throat ailments (153). The link between air pollution and the incidence of respiratory and pulmonary diseases in children, who inhale about twice as many pollutants per unit of body weight as do adults, is well-demonstrated (154) (155).
Lead Poisoning
Lead is a particular problem for children under 6. Excessive exposure impairs intelligence, growth, ability to hear and perceive language, and concentration (156). Even exposure to low levels seems to be associated with subsequent intellectual deficiencies (157) (158). The level of what is considered toxic has been continually reduced in the last 10 to 15 years as a result of new research showing how severe the consequences of lead exposure can be (159) (160).
Lead-based paint and exhaust fumes from leaded gasoline are two major sources of lead exposure; however, some children may be dangerously exposed from other sources as well. Lead workers bring home lead dust on their clothes, shoes, and hair (161). Painting, pottery glazing, jewelry making, stained glass work, metal sculpting, and other cottage craft industries that use lead or products that contain lead may involve the whole family; in Mexico, children whose families manufactured pottery were found to have higher blood-level concentrations and lower mental performance than children from families of similar socioeconomic background but who were employed in other occupations (162).
While airborne lead concentrations from industrial emissions and automobile exhaust are declining in most industrialized countries, they are increasing in developing-country urban areas (163). High levels of airborne lead have been found along busy roads in Delhi, Kuala Lumpur, and Zimbabwe (164) (165) (166). A survey of children living near a lead-smelting plant in Brazil found high levels of both zinc protoporphyrin and lead in their blood; the levels correlated to the children's age, their proximity to the plant, and length of residence (167). In Mexico City, 7 out of 10 newborns were found to have lead blood levels higher than the WHO norm (168).
Even in the United States, where the lead content of paint used for residential structures, toys, furniture, and eating utensils has been limited since 1971 (169) and unleaded gasoline has been required for new automobiles since 1975, 3-4 million children are estimated to have lead blood levels above the maximum threshold defined by the Environmental Protection Agency for neuropsychological impairment. Approximately 17 percent of all children living in metropolitan areas have blood levels in this range; among poor black children, the rate is 62 percent (170).
Water Pollution
In many developing countries, urban water sources used for drinking, washing, and cooking are threatened by biological pollution from human waste and chemical pollution from industrial toxic wastes. South America, for example, pollutes nearly 11 times more freshwater per capita than Europe, largely because less than 10 percent of its sewage is treated (171).
Infants, who need more fluids in relation to body weight than older children and adults, are particularly vulnerable to health hazards caused by water pollution. Nitrate in groundwater is a growing cause of concern in several countries, as the use of nitrate fertilizer and manure increases. Not in itself dangerous, nitrate combines with bacteria in the mouth to become nitrite, which can induce methemoglobinemia (a reduction in the oxygen-carrying capacity of the blood), especially in infants who drink baby formula mixed with water containing nitrates (172).
Hazards of Urbanization
Although urban areas have lower infant and child mortality rates in the aggregate than rural areas, the health status of urban subpopulations varies widely. The poorest urban populations--often living in illegal squatter settlements--suffer from overcrowding, inadequate housing, contaminated water supplies, poor or nonexistent waste disposal and sanitation, and exposure to industrial pollutants. Large cities tend to have the highest concentrations of water, sanitation, and health care facilities, but as many as 30-60 percent of the poorest people do not have access to them (173).
Numerous studies show that children living in these conditions have higher rates of diarrhea, respiratory infection, tuberculosis, malnutrition, and death than children in other urban communities or even in surrounding rural areas (174). Children in squatter settlements may be 50 times as likely to die before age 5 than those born in developed countries (175).
In addition, the conditions of their poverty put these urban children at increased risk of accidents, crimes, violence, and psychological harm. A growing number of children live in the streets--without shelter, adult supervision, or income.
BUILDING A GLOBAL CONSENSUS
Dramatic declines in infant mortality took place in the industrialized countries in the early 20th Century, not primarily as a result of advances in medicine, but as a direct result of advances in overall living conditions, including better nutrition, improved hygiene and sanitation, and voluntary birth limitation (176). The question today is whether further mortality decreases must wait for overall economic development or whether they can be achieved even in advance of overall improvements in the economy--by pursuing concerted strategies to improve food supply, water and sanitation, education, and health care.
For the last 10 years, WHO, UNICEF, and other multilateral agencies have urged the international community to pursue an aggressive "child survival" strategy. The program has focused on promoting wide-spread acceptance of several "technologies"--including oral rehydration therapy, breastfeeding, improved weaning practices, and immunization--and on providing increased access to food, family planning, and female literacy.
The strategy has had some outstanding successes. UNICEF in 1991 calculated that child survival interventions were saving 3.2 million young lives each year (177). But high mortality rates still prevail in many countries, and growing problems such as pediatric HIV and AIDS threaten the gains that have been made.
In the 10 countries of Central and East Africa, for example, HIV/AIDS could cause 250,000 to 500.000 additional deaths a year among children under age 5 by the year 2000. These children will be extremely sick before they die, putting severe strains on health care resources. Additionally, by the year 2000, HIV/AIDS is expected to orphan as many as 5.5 million children--11 percent of all the region's children under age 15 (178).
The World Summit for Children brought together representatives from 159 countries, including 71 heads of state or government. In a Declaration on the Survival, Protection and Development of Children, these representatives made a commitment to reduce child death rates by one third and malnutrition rates by one half by the end of the decade. The accompanying Plan of Action for meeting those goals contains detailed targets for specific diseases, nutrition, immunization, family planning, breastfeeding, water and sanitation, and education. (See Box 6.2.)
The world summit epitomized the growing global consensus that a commitment to children is important both in itself and as an investment in the sustainability of the planet. In November 1989, the United Nations adopted the Convention on the Rights of the Child, which sets standards for children's survival, health, and education and seeks to protect children who are exploited, abandoned, or abused. As of August 1991, 95 countries had ratified the Convention; another 45 had signed (but not yet ratified) it (179).
Meeting the goals set at the world summit will cost approximately $20 billion a year, according to UNICEF estimates, and will require commitments from both developing and developed countries (180). Developing countries will have to reallocate some military spending to social spending and divert some funding from hospitals and secondary education to primary health care and primary education. Additional support from industrialized countries will also be necessary to achieve these goals.
The status and progress of children's health and nutrition is a telling measure of society's overall development. Children must not only survive but be given the opportunity to thrive.
Conditions and Trends was written by World Resources Senior Editor Robert Livernash. Focus On Children's Health was written by Rosemarie Philips, a writer and editor on environment and development issues in Alexandria, Virginia. Dirk Bryant, World Resources research assistant, contributed to this chapter.
References and Notes
53. Pan American Health Organization (PAHO), Health Conditions in the Americas, Vol. I, Scientific Publication No. 524 (PAHO, Washington, D.C., 1990), p. 404.
65. "Water with Sugar and Salt," The Lancet (August 5, 1978), p. 300.
73. Op. cit. 58, pp. 1, 5, and 15.
83. Roxane M. Eikhof, Information Officer, Expanded Program on Immunization, Pan American Health Organization, Washington, D.C., September 1991 (personal communication).
96. R.R. Puffer and C. Serrano, Patterns of Mortality in Childhood, Scientific Publication No. 262, Pan American Health Organization (PAHO), Washington, D.C., 1973, cited in Health Conditions in the Americas: 1990 Edition, Vol. 1, Scientific Publication No. 524 (PAHO, Washington, D.C., 1990), Note 17, p. 116.
121. Dirk Bryant, Research Assistant, World Resources Institute, unpublished data, 1991.
127. H. Behm and E. Vargas, Guatemala: Diferencias Socioeconómicas de la Mortalidad de los Menores de dos Años 1968-1976 (Ministry of Economics, Directorate General of Statistics, Republic of Guatemala and CELADE, San Jose, Costa Rica. 1984), Senes A/1044, cited in Pan American Health Organization (PAHO), Health Conditions in the Americas: 1990 Edition Vol. I, Scientific Publication No. 524 (PAHO, Washington, D.C., 1990), p. 47.
140. Op. cit. 135, pp. 213-214.
143. United Nations (U.N.), The World's Women: 1970-1990 (U.N., New York, 1991), p.82.
167. Fernando M. Carvalho, Annibal M. Silvany-Neto, Tania M. Tavares, et al., "Lead Poisoning Among Children From Santa Amaro, Brazil," Bulletin of the Pan American Health Organization (PAHO), Vol. 19, No. 2 (PAHO, Washington, D.C., 1985), p. 168.
Source: United Nations Population Division, World Population Prospects 1990 (U.N., New York, 1991).
The crude birth rate is derived by dividing the number of live births in a given year by the midyear population. This ratio is then multiplied by 1,000.
Life expectancy at birth is the average number of years that a newborn baby is expected to live if the age-specific mortality rates effective at the year of birth apply throughout his or her lifetime.
The total fertility rate is an estimate of the number of children that an average woman would have if current age-specific fertility rates remained constant during her reproductive years.
The percentage of population in specific age groups shows a country's age structure: 0-14,15-65, and over 65 years. It is useful for inferring dependency, needs for education and employment, potential fertility, and other age-related factors. For additional details, see sources or the Technical Note for Table 16.1.
Table 16.3a, Mortality and Nutrition, 1970-95
Sources: Crude death rate and infant death rate data: United Nations Population Division, World Population Prospects 1990 (U.N., New York, 1991); Child deaths: United Nations Population Division, Mortality of Children Under Age 5: World Estimates and Projections, 1950-2025 (U.N.. New York, l988); Maternal deaths, wasting, and stunting: United Nations Children's Fund UNICEF), State of the World's Children 1991 (UNICEF, New York, 1991); Maternal deaths for Cape Verde, Comoros, Djibouti, The Gambia, Barbados, Belize, Guyana, Suriname, Bahrain, and the Solomon Islands and wasting and stunting data for Cape Verde, Djibouti. The Gambia, Liberia, Rwanda, Sierra Leone, Zaire, Barbados, Belize, Guyana, Nepal, and the Solomon Islands: United Nations Development Programme (UNDP) Human Development Report 1991 (Oxford University Press, Oxford, 1991). Per capita average calories available as a percentage of need and per capita total protein consumption: Food and Agriculture Organization of the United Nations (FAO), Agrostat PC (FAO, Rome, July 1991).
The crude death rate is derived by dividing the number of deaths in a year by the midyear population, and multlplying by 1,000.
The infant death rate is derived by dividing the number of babies who die before their first birthday by the number of live births in that year, and multiplying by 1,000.
Child deaths are derived by dividing the number of children under age 5 who die in a given year by the number of live births in that year, and multiplying by 1,000. Infant and child death rates are projected from the latest estimates available from the United Nations Population Division. These death rates are not comparable because different parameters were used in modeling projected changes.
Maternal deaths are the number of deaths from pregnancy- or childbirth-related causes per 100,000 live births. A maternal death is defined by the World Health Organization (WHO) as the death of a woman while pregnant or within 42 days of termination of pregnancy from any cause related to or aggravated by the pregnancy, including abortion. Most official maternal mortality rates are underestimated because causes of death are often incorrectly classified or unavailable. In some countries, over 60 percent of women's deaths are registered without a specified cause. Maternal deaths are highest among women of ages 10-15 years, and over 40 years, and in women with five or more children. Data are provided to UNDP and UNICEF by WHO and refer to a single year between 1980 and 1988 (1980 to 1987 for UNDP data). Data for some countries are outside the range of years indicated.
Wasting indicates current acute malnutrition and refers to the percentage of children between the ages of 12 and 23 months whose weight-for-height is less than 77 percent of the median weight-for-height of the reference population of the U.S. National Center for Health Statistics (NCHS). Stunting, an indicator of chronic undernutrition, refers to the percentage of children between the ages of 24 and 59 months whose height-for-age is less than 77 percent of the median. NCHS, among others, has found that healthy children under the age of 5 years do not differ appreciably in weight or height. WHO has accepted the NCHS weight-for-age and weight-for-height standards. Children with low weight-for-age are at a high risk of mortality. Data on wasting and stunting, provided to UNDP and UNICEF by WHO, refer to a single year between 1980 and 1989 (1980 to 1988 for UNDP data). Data for some countries are outside the range of years or ages indicated.
The per capita average calories available (as percent of need) and the per capita total protein consumption are calories and protein from all food sources: domestic production, international trade, stock drawdowns, and foreign aid. Total protein is the amount provided from animal and vegetable food sources. The quantity of food available for human consumption, as estimated by FAO, is the amount that reaches the consumer. The calories and protein actually consumed may be lower than the figures shown, depending on how much is lost during home storage, preparation, and cooking, and how much is fed to pets and domestic animals or discarded. Estimates of daily caloric requirements vary for individual countries according to the age distribution and estimated level of activity of the population.
Table 16.4a, b Access to Safe Drinking Water, Sanitation, and Health Services, 1980s
Sources: Drinking water and sanitation: World Health Organization (WHO), The International Drinking Water Supply and Sanitation Decade: Review of Mid-Decade Progress (as at December 1985) (WHO, Geneva, September 1987); WHO, The International Drinking Water Supply and Sanitation Decade: Review of National Progress (as at December 1983); WHO, The International Drinking Water Supply and Sanitation Decade: Review of National Baseline Data: December 1980 (WHO, Geneva, 1984); WHO, Global Strategy for Health for All. Monitoring 1988-1989. Detailed analysis of global indicators (WHO, Geneva, May 1989), and unpublished data (WHO, Geneva, July 1991). Access to health services: United Nations Children's Fund (UNICEF), State of the World's Children 1991 (UNICEF, New York, 1991). Numbers of trained medical personnel: WHO, 1988 World Health Statistics Annual (WHO, Geneva, 1988).
WHO collected data on drinking water and sanitation from national governments in 1980, 1983, 1985, and 1988 using questionnaires completed by public health officials, WHO experts, and Resident Representatives of the United Nations Development Programme. Data for a number of countries were gathered during 1986-87. For several countries in Africa. dates were not given. Urban and rural populations were defined by each national government.
WHO defines reasonable access to safe drinking water in an urban area as access to piped water or a public standpipe within 200 meters of a dwelling or housing unit. In rural areas, reasonable access implies that a family member need not spend a disproportionate part of the day fetching water. "Safe" drinking water includes treated surface water and untreated water from protected springs, boreholes, and sanitary wells.
Urban areas with access to sanitation services are defined as urban populations served by connections to public sewers or household systems such as pit privies, pour-flush latrines, septic tanks, communal toilets, and other such facilities. Rural populations with access were defined as those with adequate disposal such as pit privies, pour-flush latrines, and so forth. Application of these definitions may vary, and comparisons can therefore be misleading.
The population with access to health services is defined by UNICEF as the percentage of the population that can reach local health services by local transport in no more than one hour.
Data on number of trained medical personnel are the latest available to WHO regional offices at the beginning of 1988. Most are from 1983-86; however, some go back to 1977. Comparisons should be made with care, since categories and definitions vary among countries.
Health care personnel have been combined into three categories:
Doctors: all physicians or surgeons;
Nurses and midwives: all registered nurses and others in categories in which the term "nurse" or "nursing" appears; all midwives, birth attendants, and others in categories in which the term "midwife" appears;
Other: all others directly involved in diagnosis, treatment, and prevention of disease (e.g., dentists, paramedical personnel, medical assistants, acupuncturists), and all other reported categories (e.g., pharmacists, laboratory technicians, x-ray technicians, and hospital administrators).
Access to health personnel can vary substantally within a country. The degree of access in individual countries can be partly inferred from other health data (e.g., infant deaths, immunizations) presented here.
Table 16.5a, b Education and Child Health, 1970-90
Sources: Adult literacy for 1970: United Nations Children's Fund (UNICEF), State of the World's Children l989 and State of the World's Children 1991 (UNICEF, New York, 1989 and 1991); Adult literacy for 1990: United Nations Educational, Scientific and Cultural Organization (UNESCO). Compendium of Statistics on Illiteracy-1990 Edition (UNESCO, Paris, 1990); The percentage of population age 25 and over who have completed primary school and who have some postsecondary education: United Nations Educational, Scientific and Cultural Organization (UNESCO) Statistical Yearbook 1990 (UNESCO, Pans, 1990); Births attended by trained personnel, ORT use, and low-birthweight infants: UNICEF, State of the World's Children 1991 (UNICEF, New York, 1991) Births attended by trained personnel for Cape Verde, Comoros, Djibouti, Equatorial Guinea, The Gambia, Guinea-Bissau, Swaziland, Barbados, Belize, Guyana, Sunname, Bahrain, Yemen, Fiji and the Solomon Islands and low-birth-weight infants for Chad, Comoros, Djibouti, The Gambia, Guinea-Bissau, Barbados, Belize, Guyana, and Suriname: United Nations Development Programme (UNDP). Human Development Report 1991 (Oxford University Press, New York, 1991); TB, DPT, polio, and measles immunization: UNICEF, unpublished data, September 1991.
Adult female and adult male literacy rates refer to the percentage of people over the age of 15 who can read and write. UNESCO recommends defining as illiterate a person who cannot both read with understanding and write a short and simple statement on his or her everyday life. This concept is widely accepted, but its interpretation and application vary. It does not include people who, though familiar with the basics of reading and writing, do not have the skills to function at a reasonable level in their own society. Actual definitions of adult literacy are not strictly comparable among countries. Literacy data for 1990 are projected from past census figures, using estimates of age group size within country populations when available.
The percentage of population age 25 and over who have completed primary school and who have some postsecondary education are figures based largely on national censuses and sample surveys taken between 1970 and 1989. Primary education is defined as category 1 of the International Standard Classification of Education (ISCED). The length of primary education varies by country from three to nine years. The median length for all countries is six years for primary education, and five and a half years for secondary education. Postsecondary education consists of ISCED categories 5, 6, and 7. These categories include education at universities, technical schools, and teacher-training institutes.
The percentage of births attended by trained personnel includes all health personnel accepted by national authorities as part of the health system. Personnel included vary by country. Some countries include traditional birthing assistants and midwives; others, only doctors. WHO provides the data to UNICEF.
ORT (oral rehydration therapy) use refers to administration of oral rehydration salts to children to combat diarrheal disease leading to dehydration or malnutrition.
The percentage of low-birth-weight infants refers to all babies weighing 2,500 grams or less at birth. WHO has adopted the standard that healthy babies, regardless of race, should weigh more than 2,500 grams at birth. These data are provided to UNICEF by WHO, and refer to a single year between 1980 and 1988.
Immunization data show the percentage of 1-year-olds fully immunized in 1990 against: TB (tuberculosis); DPT (diphtheria, pertussis [whooping cough], and tetanus); polio; and measles. Data for measles immunizations include totals from countries where this vaccination is normally given to children after 1 year of age.
