Towards a recycling society: ecological sanitation--closing the loop to food security.

A recycling society must switch from linear solutions to circular approaches, protecting ecosystems and harmonising with natural systems. Ecological sanitation, an alternative to conventional approaches, considers excreta a resource. Excreta are rendered safe at the source prior to reuse. The ecosystem approach helps restore soil fertility, and ultimately enhances food security. It is a system requiring little or no water; thus it conserves and protects fresh and marine water sources, enhances biodiversity, and it may confer multiple benefits in urban settings. It can generate jobs, be financially more affordable than conventional approaches, improve local ecology, create decentralised economies, and contribute toward improved health and nutrition of people. Ecological sanitation closes water and nutrient loops, reducing reliance on external inputs and reducing output of wastes from the system.

Rethinking sanitation: panacea or Pandora's box.

In the 19th century, sanitation solutions were designed and built on the premises that human excreta was a waste suitable only for disposal and that the environment was capable of assimilating the waste. The prevailing view last century was that vapors from smells caused disease, and the best way to deal with excreta was to convey it to rivers and streams where it could be diluted and cleansed. Times have changed, the premises are outdated, and current solutions contribute, either directly or indirectly, to many of the problems faced by society today: water pollution, scarcity of fresh water, food insecurity, destruction and loss of soil fertility, loss of biodiversity, depletion of the ozone layer, and global warming. A common denominator of all these problems is how society deals with its wastes, specifically how it deals with human excrement. We have to rethink past premises, design and build new systems, and contribute to the solving of society's most pressing problems. The panacea of the 19th century is turning out to be the pandora's box of the 21st century.

Risk factors for iron deficiency anaemia in preschool children in northern Ethiopia.

OBJECTIVE: To determine risk factors for anaemia in preschool children. DESIGN: A cross-sectional study. SETTING: Tigray province, northern Ethiopia. SUBJECTS: 2080 of 2373 children aged 6-60 months provided blood to assess anaemia. RESULTS: Anaemia was highly prevalent (42%) and constituted an important nutritional problem in the region. In a sub-sample of 230 anaemic children, 56% had a low red blood cell (RBC) count, and 43% had a serum ferritin of less than 12 microgl(-1) indicating that the anaemia was largely due to iron deficiency. Unlike other regions in developing countries, hookworm (0.4%) and malaria (0.0%) were rare and contributed little to the anaemia. Even though their diet lacked variety, the amount of iron consumed through cereal-based staple foods was adequate. However, the iron in these foods was not readily available and their diets were probably high in iron absorption inhibitors and low in enhancers. Dietary factors associated with anaemia included frequent consumption of inhibitors, such as fenugreek and coffee, and poor health in the child such as diarrhoea and stunting. CONCLUSIONS: Underlying causes of anaemia were lack of safe water and inadequate human waste management, maternal illiteracy and mother being ill, and having no food reserves. The root cause of these factors was poverty. The optimal control strategy for iron deficiency anaemia should have a holistic approach which includes the alleviation of poverty, the empowerment of women and the provision of a safe environment.

Effect of consumption of food cooked in iron pots on iron status and growth of young children: a randomised trial.

BACKGROUND: In less-developed countries, novel strategies are needed to control iron-deficiency anaemia, the most common form of malnutrition. METHODS: We undertook a community-based randomised controlled trial to assess the effects of iron or aluminium cooking pots in young Ethiopian children. Analysis was by intention-to-treat. The primary outcomes were change in children's haemoglobin concentration, weight, or length over the study period. We also did a laboratory study of total and available iron in traditional Ethiopian foods cooked in iron, aluminium, and clay pots. FINDINGS: 407 children, one per household, entered the study. The change in haemoglobin concentration was greater in the iron-pot group than in the aluminium-pot group (mean change to 12 months 1.7 [SD 1.5] vs 0.4 [1.0] g/dL; mean difference between groups 1.3 g/dL [95% Cl 1.1-1.6]). The mean differences between the groups in weight and length gain to 12 months (adjusted for baseline weight or length) were 0.6 cm (95% CI 0.1-1.0) and 0.1 kg (-0.1 to 0.3). The laboratory study showed that total and available iron was greatest in foods cooked in iron pots, except for available iron in legumes for which there was no difference between types of pot. INTERPRETATION: Ethiopian children fed food from iron pots had lower rates of anaemia and better growth than children whose food was cooked in aluminium pots. Provision of iron cooking pots for households in less-developed countries may be a useful method to prevent iron-deficiency anaemia.

Continued breastfeeding and child growth in the second year of life: a prospective cohort study in western Kenya.

BACKGROUND: The value of postinfancy breastfeeding for growth and nutritional status is debated. We have investigated this issue in a longitudinal study. METHODS: We prospectively followed up a cohort of 264 children in western Kenya for 6 months (mean age 14 months [range 9-18] at baseline) to investigate the nature of the association between breastfeeding and growth. Only 14 (5.3%) children had been weaned at baseline, and 173 (65.5%) were still breastfed at follow-up. For analysis, children were classified into three groups of breastfeeding duration as a proportion of the total follow-up period (0-49%, n=42; 50-99%, n=49; and 100%, n=173). FINDINGS: In general linear models multivariate analysis, children in the longest-duration breastfeeding group gained 3.4 cm (p=0.0001) and 370 g (p=0.005) more than those in the shortest duration group, and 0.6 cm (p=0.0015) and 230 g (p=0.038) more than children in the intermediate group. The strongest association between breastfeeding and linear growth was observed in households that had no latrine and daily water use of less than 10 L per person. INTERPRETATION: Our findings support WHO's recommendation to continue breastfeeding for at least 2 years, especially in settings with poor sanitation and inadequate water supply.

PIP: This prospective cohort study aimed to investigate growth in the second year of life in relation to continued breast-feeding in western Kenya. A total sample of 134 girls and 130 boys with the mean age of 14 months at enrollment was followed up for 6 months. Of the 264 children, only 14 (5.3%) had been weaned at baseline, and 173 (65.5%) were still breast-fed at follow-up. Children were classified into three groups of breast-feeding duration as a proportion of the total follow-up period (0-49%, n = 42; 50-99%, n = 49; 100%, n = 173). Analysis showed that children in the longest-duration group gained 3.4 cm (p = 0.0001) and 370 g (p = 0.0005) more than those in the shortest duration group, and 0.6 cm (p = 0.0015) and 230 g (p = 0.038) more than children in the intermediate group. In addition, the strongest association between breast-feeding and linear growth was observed in households that had no latrine and daily water use of less than 10 liters/person. In conclusion, the findings suggested that continued breastfeeding during the second year of life had a positive impact on a child's linear growth.

Randomised trial of albendazole and pyrantel in symptomless trichuriasis in children.

BACKGROUND: We aimed to find out whether symptomless infection with Trichuris trichiura is associated with impairment of growth and to assess the effect of a multiple-doses regimen of anthelmintic drugs on the growth of children. METHODS: In a community based trial, 622 Mexican children were randomly allocated one of three treatment regimens: 3 days of albendazole 400 mg daily (high efficacy); one dose of albendazole 400 mg (moderate efficacy); one dose of pyrantel (pyrantel embonate) 11 mg/kg (low efficacy). Growth was monitored for 12 months. Analyses were by intention to treat. FINDINGS: 113 (18%) children were lost to follow-up--34 from the pyrantel group, 45 from the albendazole 400 mg group, and 34 from the albendazole 1200 mg group. Among the 127 children with heavy pretreatment infections, albendazole 1200 mg was better than pyrantel in terms of an increase in arm circumference (mean 0.26 cm, p=0.044). Among the 381 children with low pretreatment levels of infection, changes in weight (mean difference between groups -0.33 kg, p=0.036), arm circumference (-0.18 cm, p=0.0095), and thickness of triceps skinfold (-0.41 mm, p=0.0031) were less in children on albendazole 1200 mg than in those on pyrantel. INTERPRETATION: Symptomless trichuriasis impairs growth and albendazole or pyrantel may affect growth, independently of a therapeutic action on parasites. Possible toxic effects of high-dose albendazole require further investigation.

Water, waste, and well-being: a multicountry study.

Data collected in the late 1980s from eight countries in Sub-Saharan Africa (Burundi, Ghana, Togo, and Uganda), Asia/North Africa (Sri Lanka and Morocco), and the Americas (Bolivia and Guatemala) were combined and analyzed to test whether incremental health effects regarding diarrhea and nutritional status result from incremental improvements in water and sanitation conditions. Rural (n = 11,992) and urban (n = 4,888) samples were analyzed separately. Optimal (i.e., on the premises) and intermediate (improved public water) water supplies were compared with unimproved water conditions. Optimal (flush toilets or water-seal-latrines) and intermediate (latrines) sanitation levels were compared with unimproved sanitation. Nationally representative (random) samples of ever-married women age 15-49 years, with or without children, were interviewed in all countries, and children aged 3-36 months with available weight and height data were included in the analyses. Multiple linear regression controlled for household, maternal, and child-level variables; in addition, dummy variables were included for each country. Improvements in sanitation resulted in less diarrhea and in taller and heavier children with each of the three levels of water supply. Incremental benefits in sanitation were associated with less diarrhea and with additional increases in the weights and heights of children. The effects of improved sanitation were greater among urban dwellers than among rural dwellers. Health benefits from improved water were less pronounced than those for sanitation. Benefits from improved water occurred only when sanitation was improved and only when optimal water was present. These findings suggest that public health intervention should balance epidemiologic data with the cost of services and the demand for water. There should be efforts to develop compatible technologies so that incremental improvements in service can be made.

Evaluation of a face-to-face weaning food intervention in Kwara State, Nigeria: knowledge, trial, and adoption of a home-prepared weaning food.

This paper reports on the evaluation of a pilot intervention which used nutrition education techniques to introduce a fortified, home-prepared weaning food (eko ilera, or 'pap for health') in 12 communities in Kwara State, Nigeria, from June to August, 1988. The recipe added toasted cowpea flour, red palm oil, and sugar to increase the energy and protein density of the traditional maize or sorghum starch porridge used for weaning from 38 to 85 kcal and 0.8 to 2.0 g protein per 100 g. A stratified, random sample of participating (n = 295) and non-participating (n = 301) mothers from the same communities were interviewed from 2 to 8 weeks following the completion of the intervention, and their rates of knowledge, trail, and adoption of eko ilera were evaluated. Of the participating mothers, 57% (95% CI: 51%, 63%) knew the modified recipe, 48% (43%, 54%) tried it, and 17% (12%, 21%) adopted it with the intention of using it in the future. Only 2% (1%, 7%) of non-participating mothers knew about the recipe. Multivariate analyses indicated that the mothers' level of education and their perception of the cost and length of preparation time of the recipe were significantly associated with its adoption. The intervention was successful in using face-to-face nutrition education methods to introduce eko ilera to mothers in this region of Nigeria and to encourage its trial and adoption.

The complementary effect of latrines and increased water usage on the growth of infants in rural Lesotho.

The effects of water quantity and sanitation, alone and in combination with each other, on infant weight gain and length gain were examined. Data on 119 infants were collected from 20 villages in rural Lesotho between July 1984 and January 1985. The interactions between sanitation and increased water usage for weight gain (p = 0.007) and length gain (p = 0.006) were significant after potential confounding was controlled. The biggest growth effects were dependent on families possessing a latrine and increasing their use of water during the warm, wet season. Infants gained 1.031 kg (95% confidence interval (CI) 0.420 to 1.642) and 2.028 cm (95% CI 0.523 to 3.533) more when both positive factors were present, as compared with only having a latrine. Increasing water usage compared with not increasing water usage resulted in only 0.105 kg (95% CI -0.175 to 0.385) more weight gain and -0.309 cm (95% CI -1.005 to 0.387) more length in the absence of a latrine. Similarly, infants gained 1.106 kg (95% CI 0.484 to 1.728) and 2.076 cm (95% CI 0.559 to 3.593) more if both factors were operating than did infants whose families only increased their water usage. In the nonincreased water group, the difference in growth between having and not having a latrine was 0.180 kg (95% CI -0.093 to 0.453) and -0.261 cm (95% CI -0.951 to 0.429). Water supply programs should emphasize use of more water for personal hygiene, and sanitation programs should install toilet facilities where water usage is high or has been increased because of an educational program.

PIP: Researchers analyzed data on 119 infants who lived in 20 villages in Lesotho from a 6 month period in 1984-1985 to evaluate the effect of latrines and increased water use on growth. 62% of the infants lived in families that did not have a latrine and did not increase water use between the 2 seasons. Only 3% increased water use and had a latrine. 19% had a latrine, but did not increase water use. 16% increased water use, but did not have a latrine. Infants from a family with a latrine which increased water use gained 1.031 kg more than those infants with a latrine but no increased water use (p=.0007). Among infants who did not have a latrine, the effect of not increasing water use was a meager 0.105 kg. Infants from a family with increased water use and a latrine gained 1.031 kg more than those who did not have a latrine (p=.0007). Among children whose families did not increase water use, the difference between having a latrine and not having a latrine was only 0.18 kg. Infants from a family which increased water use and had a latrine grew 2.076 cm more than those infants in a family which increased water use and did not have a latrine (p=.0007). Among infants who did not have a latrine, the effect of not increasing water use was a meager 0.261 cm. Infants from a family with a latrine and increased water use grew 2.2w028 cm more than infants with latrine but did not increase water use (p=.007). Among children whose families did not increase water use, the difference between having a latrine and not having a latrine was only 0.309 cm. These results demonstrated the complementary effect of latrines and increased water use which may have prevented pathogens from contaminating the environment and the quantity of pathogens ingested.

Effects of improved water supply and sanitation on ascariasis, diarrhoea, dracunculiasis, hookworm infection, schistosomiasis, and trachoma.

A total of 144 studies were analysed to examine the impact of improved water supply and sanitation facilities on ascariasis, diarrhoea, dracunculiasis, hookworm infection, schistosomiasis, and trachoma. These diseases were selected because they are widespread and illustrate the variety of mechanisms through which improved water and sanitation can protect people. Disease-specific median reduction levels were calculated for all studies, and separately for the more methodologically rigorous ones. For the latter studies, the median reduction in morbidity for diarrhoea, trachoma, and ascariasis induced by water supplies and/or sanitation was 26%, 27%, and 29%, respectively; the median reduction for schistosomiasis and dracunculiasis was higher, at 77% and 78%, respectively. All studies of hookworm infection were flawed apart from one, which reported a 4% reduction in incidence. For hookworm infection, ascariasis, and schistosomiasis, the reduction in disease severity, as measured in egg counts, was greater than that in incidence or prevalence. Child mortality fell by 55%, which suggests that water and sanitation have a substantial impact on child survival. Water for personal and domestic hygiene was important in reducing the rates of ascariasis, diarrhoea, schistosomiasis, and trachoma. Sanitation facilities decreased diarrhoea morbidity and mortality and the severity of hookworm infection. Better water quality reduced the incidence of dracunculiasis, but its role in diarrhoeal disease control was less important than that of sanitation and hygiene.

PIP: Researchers reviewed 144 water and sanitation interventions conducted in various developing countries and in the US to look at the effect improved water supply and sanitation facilities had on ascariasis, diarrhea, dracunculiasis, hookworm infection, schistosomiasis, and trachoma. This review showed that improved water supply and sanitation facilities resulted in substantial reductions in morbidity of diarrhea (26%), ascariasis (29%), guinea worm infection (78%), schistosomiasis (77%), and trachoma (27%). Only 1 study of hookworm infection was not flawed and it demonstrated only a 4% reduction in incidence. Moreover accurate studies demonstrated a median reduction in diarrhea specific mortality of 65% and 55% in general child mortality. The researchers supposed that those studies that demonstrated reductions in morbidity for at least 1 disease did not give water and sanitation their complete due in improving health, especially those where 1 disease was prevalent in the intervention area. Some studies revealed that chemotherapy combined with improvement in water and sanitation prevented infection rates of some parasitic diseases from returning to pretreatment levels. Further the duration of infection fell 50% of the incidence or prevalence, e.g., ascariasis, schistosomiasis, and hookworm infection. Moreover, studies revealed reductions in childhood diarrhea and overall mortality were greater than diarrhea incidence or prevalence. Interventions which included improved excreta disposal and water quantity resulted in greater impacts than improvements in water quality. The review concluded with recommendations which included providing water as close to the home as possible to encourage use of large amounts of water for hygienic practices and hygiene education being integrated into water supply and health programs.

Effect of diarrhoea on dietary intake by infants and young children in rural villages of Kwara State, Nigeria.

Community-based, quantitative studies of dietary intake by 5- to 28-months-old Nigerian children were conducted during episodes of diarrhoea and subsequent convalescent and healthy periods. Energy intakes during diarrhoea (85.3 kcal/kg per d) were slightly lower than during health (95.9 kcal/kg per d, P less than 0.05), using paired analysis of intra-individual differences. When intake was disaggregated by food source, no differences by illness status were found in energy intake from breast milk or liquid pap. There were no differences in frequency or duration of breastfeeding by illness status, but pap was provided more frequently and in smaller amounts during illness. Energy intake from other foods, including solids, was greater during health than diarrhoea (P less than 0.05) with an increase in number of servings per day. There was no evidence of caretakers either withholding food during illness or providing extra food during the convalescent phase. The magnitude of illness-associated differences in these children's daily intake was small relative to the deficit in their intakes, even on healthy days, when compared to the amounts recommended for this age group.

The use of residuals for longitudinal data analysis: the example of child growth.

Health impact evaluations often measure changes in health status over part of a total life experience. The effects on health up to and including the start of the evaluation, which are embodied in the measure of initial health status, need to be removed while examining the effects that other variables exert during the evaluation period on final health status. Statistical models, which include initial health status as a covariate while examining the effects of other variables during the evaluation, confound the effects of a determinant during evaluation with preevaluation effects, because they do not differentiate between effects produced at different times by the same determinant. A residual model removes the preevaluation effects by regressing final health status on initial health status. The residuals from this regression are then regressed on the other predictor variables. In this paper, standard covariate adjustment, which includes all effects simultaneously, is compared with a two-part residual model using child growth as an example. The simultaneous model over- and underpredicts growth relative to the residual model depending on the age and initial body size of a child. In general, whenever initial (preintervention) and final (postintervention) measures of health outcome exist, the residual model should be considered on the basis of biologic and epidemiologic consideration, not solely on statistical optimality.

The risk of infection from Giardia lamblia due to drinking water supply, use of water, and latrines among preschool children in rural Lesotho.

Stool samples were collected from 267 rural, preschool children in four districts in Lesotho during October-November, 1984. Sixty-three children (23.6%) were tested positive for Giardia lamblia, the most commonly recovered parasite from stool samples. The use of low amounts of water for personal hygiene was associated significantly with having G. lamblia (OR = 2.42), but the use of traditional, non-improved drinking water sources (OR = 1.38) or lack of latrines (OR = 0.94) was not. Although G. lamblia may be primarily waterborne in developed countries, the amount of water that is used for personal and domestic hygiene may be more important than the quality of drinking water in developing countries. Other risk factors that were identified to be associated significantly with having or not having Giardia were child older than 24 months (OR = 6.79), mother less than 20 years of age (OR = 5.18), residing in Mohales Hoek district (OR = 2.33), and possessing several agricultural tools (OR = 0.70).

Shedding of coronavirus-like particles by children in Lesotho.

Stools from 266 children in four districts of Lesotho were examined for viruses by electron microscopy (EM) over a 5-week period. Eighty one (30.5%) of the children shed coronavirus-like particles (CVLPs). Shedding was not significantly associated with diarrhea. The proportion of children shedding these particles increased with increasing age. In one district, the prevalence of CVLP shedding (67.9%) was at least twice the prevalence in any of the other three districts. This was the only district to be sampled during the first week of the study. It was shown that the proportion of children shedding CVLPs declined during each of the 5 weeks of study. The stools of six children who shed CVLPs in the early summer of 1984-85 were negative by EM 5 months later. There was no association between the shedding of pathogenic bacteria or parasites and the presence or absence of CVLPs in the stool.

Drinking water source, diarrheal morbidity, and child growth in villages with both traditional and improved water supplies in rural Lesotho, southern Africa.

This study examined the growth and morbidity rates of young children in relation to exclusive and non-exclusive use of improved water supplies in rural Lesotho, southern Africa. Data were collected for 247 children 60 months of age and under between July 1984 and February 1985 in 10 villages that had an improved water supply at least one year prior to investigation. Children whose families relied exclusively on the new water supply for their drinking and cooking needs grew 0.438 cm and 235 g more in six months than children whose families supplemented the new water supply with the use of contaminated traditional water for drinking and cooking. The difference in growth was greater among children over 12 months of age at the start of the evaluation than among infants. This may be explained partly by lower rates for Giardia lamblia, the most commonly identified pathogen in stools in older children. Among infants, similar rates of Campylobacter, the most commonly isolated pathogen among infants, may have prevented larger differences. Results suggest that improved drinking water supplies can benefit preschool children's health after infancy, but only if they are functioning and utilized exclusively for drinking and cooking purposes.

Maternal literacy modifies the effect of toilets and piped water on infant survival in Malaysia.

The effect of toilets, piped water, and maternal literacy on infant mortality was analyzed using data from the Malaysian Family Life Survey collected in 1976-1977. The effect of toilets and piped water on infant mortality was dependent on whether or not mothers were literate. The impact of having toilets was greater among the illiterate than among the literate, but the impact of piped water was greater among the literate than among the illiterate. The effect on the infant mortality rate for toilets decreased from 130.7 +/- 17.2 deaths in the absence of literate mothers to 76.2 +/- 25.9 deaths in the presence of literate mothers. The reduction in the mortality rate for maternal literacy dropped from 44.4 +/- 14.1 deaths without toilets to -10.1 +/- 23.9 deaths with toilets. Reductions in mortality rates for piped water increased from 16.7 +/- 12.7 deaths without literate mothers to 36.8 +/- 21.0 deaths with literate mothers. Similarly, reductions in the mortality rate for maternal literacy rose from 44.4 +/- 14.1 deaths in the absence of piped water to 64.5 +/- 19.5 deaths in the presence of piped water. The results from a logistic model provided inferences similar to those from ordinary least squares. The authors infer that literate mothers protect their infants especially in unsanitary environments lacking toilets, and that when piped water is introduced, they use it more effectively to practice better hygiene for their infants.

Interventions for the control of diarrhoeal diseases among young children: improving water supplies and excreta disposal facilities.

A theoretical model is proposed that relates the level of ingestion of diarrhoea-causing pathogens to the frequency of diarrhoea in the community. The implications of this model are that, in poor communities with inadequate water supply and excreta disposal, reducing the level of enteric pathogen ingestion by a given amount will have a greater impact on diarrhoea mortality rates than on morbidity rates, a greater impact on the incidence rate of severe diarrhoea than on that of mild diarrhoea, and a greater impact on diarrhoea caused by pathogens having high infectious doses than on diarrhoea caused by pathogens of a low infectious dose. The impact of water supply and sanitation on diarrhoea, related infections, nutritional status, and mortality is analysed by reviewing 67 studies from 28 countries. The median reductions in diarrhoea morbidity rates are 22% from all studies and 27% from a few better-designed studies. All studies of the impact on total mortality rates show a median reduction of 21%, while the few better-designed studies give a median reduction of 30%. Improvements in water quality have less of an impact than improvements in water availability or excreta disposal.