​​​The FRESH framework, an intersectoral initiative to Focus Resources on Effective School Health, provides the context for health and nutrition services within school health programs.  School based health and nutrition services, such as micronutrient supplementation and deworming, are likely to be most effective where they are supported by other strategies such as school health policies to provide a non-discriminatory safe and secure environment, provision of safe water and sanitation, and skills based health education.  They are also likely to be most effective when they include referral to external health service providers and links with other community services.  The FRESH framework provides this context by positioning school based o health and nutrition services among its four core components that should be made available together for all schools:

Health related school policies
Safe water and sanitation
Skills based health education​
Access to health and nutrition services

There are now more school-age children in developing countries than ever before, due to population growth and the success of child survival programs.  At the same time, there are more children in school as access to basic education has increased in most of the developing world.   However, millions of school-age children remain at risk due to poor health and nutrition.  There is increasing recognition that the common conditions of ill health among school children can be dealt with effectively, simply and cheaply through school health and nutrition programs that include school based health and nutrition services, along with supportive school health policies, safe water and sanitation and skills based health education, including hygiene. 

 

1. Why School Based Health and Nutrition Services?

School health programs and services help link the resources of the health, education, nutrition, and sanitation sectors in an existing infrastructure, the school.  While the school system in most developing countries is rarely universal, coverage is generally superior to health systems and there is an extensive skilled workforce (teachers and administrators) that already works with the local community.

School based health and nutrition services often include screening for health problems,  providing simple and easy to administer medications and treatments  such as micronutrient supplements (including vitamin A, iron and iodine), and anthelmintics for treatment of parasitic helminth infections by teachers; education and advice about health; and referral to other health and community services, as available.  As such, school health and nutrition services  offer an effective way of improving the health and nutritional status of children (Partnership for Child Development 2000, Mwanri et al. 2000, Beasley et al. 2000),  especially when they are supported school health policies,  adequate water and sanitation and skills based health education, including  hygiene education.

Data show that the prevalence of stunting increased with age showing a higher proportion of stunted school-aged children. It also appears that adolescent boys are more sensitive to infection and diseases than girls, and thus are more malnourished.  In addition, studies have shown that linear growth continues beyond the normal puberty growth period.  This suggests that school based programs aimed at improving health and nutrition status may have the potential to bring about catch-up growth in stunted school aged children (Stoltzfus et al., 1998).

As more countries adopt universal basic education strategies, increased enrolment and reduced absenteeism and drop out bring more of the poorest and most disadvantaged children to school, many of them girls.  It is these children who are often the least healthy and most malnourished, and who have the most to gain educationally from improved health (Odaga & Heneveld, 1995; Bundy & Guyatt, 1996).   

These services are also highly cost-effective: the cost of drugs for treating parasitic worms in the Partnership for Child Development's school health programs in Ghana and Tanzania was typically about US$0.40 per year per child treated for albendazole (to treat soil-transmitted helminthiasis) given annually, plus praziquantel (schistosomiasis) given every two years.  The cost of two capsules of iodized oil – each providing 200 mg of iodine, enough for a typical primary school child – was about US$0.40 (Partnership for Child Development, 1999). 

These and other health and nutrition services can also serve as an opportunity for   improving school health programmes  by considering the ways in which school health policies, a healthy school environment  and skills-based health education,   can complement such services.  They also provide opportunities for the wider involvement of the local community and other key stakeholders in improving education and health.  Interviews and discussions with children, parents and implementers in Tanzania and Ghana have found that the large majority agree with the role of schools and teachers in school based health service delivery and a willingness by parents to meet either part or all of the costs.  Both the family and the community view the delivery of health and nutrition services through schools as a positive activity in their community (Partnership for Child Development, 2001).  

Beyond the benefits to both the family and community, school based health services that impact on poor health and nutrition are likely to benefit society as a whole.  The consequences of stunting caused by malnutrition include increased morbidity and mortality, poor physical and mental development and school performance, and reduced body size and capacity for physical growth- all of which have long-term economic and societal implications.  School health programs that target poor health and nutrition are therefore an investment in a country's people and their capacity to thrive both economically and as a society (Stephenson, Latham and Ottesen, 2000).

 

2. School-based Health and Nutrition Services: deworming

The World Health Organization (WHO) estimates that more than one billion of the world's population is chronically infected with soil-transmitted helminths and 200 million are infected with schistosomes.  Global prevalence and number of cases of intestinal helminth infection in school-age children are estimated at: Roundworm 35% (320 million); Whipworm 25% (233 million); Hookworm 26% (239 million) (Partnership for Child Development, 1997).

Exposure and susceptibility to worm infections are not uniform and, as Figure 1 demonstrates, it is the school age child who is most at risk from intense infections.  As intensity of infection is directly related to morbidity, it is clear that it is the school-age child who is most at risk from disease.  For girls and boys aged 5 to 14 years, in developing countries these worm infections account for an estimated 12 and 11 percent of the total disease burden respectively, and represent the single largest contributor to the disease burden of this age group (Bundy, 1988). A community survey in Jamaica showed, for example, that for intestinal nematodes, some 90% of the total worm population occurred in children between 5 and 15 years of age.

 

 

 

Fig 1. Worm Infection by Age (adapted from Bundy 1988).

As children are most at risk at an age when they are both growing and learning, geohelminth infection potentially threatens a child's overall physical and psychological development.  Parasitic helminth infection may cause or aggravate malnutrition and retard child development (Stephenson, Latham and Ottesen, 2000). 

Anthelmintics may reverse growth and nutritional deficits caused by even modest worm infection.  Intervention studies have shown that infection with as few as ten roundworms is associated with deficits in growth of school-age children and that moderate whipworm infections can cause growth retardation and anemia.  In the case of more severe infection, children infected with Trichuris dysentery syndrome show "catch-up growth" after treatment of intense infections with whipworm, and other intervention studies have shown a positive impact on anthropometrical parameters and iron status of preschool and school age children with helminth infections (Drake et al., 2000).  

Physical ill health caused by parasitic helminth infection negatively impacts on a child's mental function.  There is a proven link between iron deficiency anemia, stunting and cognitive development.  In addition, although the evidence is as yet inconclusive, it is likely that helminths do impair cognitive development.  However, this may occur only for those children with the heaviest parasitic loads or for those already vulnerable in other ways, such as from under nourishment (Drake et al., 2000).  

The high prevalence of infections and the development of effective and safe single-dose treatments for worms have led the WHO to recommend mass treatment througfh schools where surveys show that the prevalence of intestinal helminths or schistosoma infections exceeds 50% (WHO, 1998): albendazole or mebendazole for treating roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura) and hookworm (Necator americanus, Ancylostoma duodenale) and praziquantel for treating schistosomes) are the recommended drugs.

In addition, population dynamic theory has predicted that focusing treatment effort on this age group would significantly reduce transmission in the population as a whole (Bundy et al., 1990).  Large-scale field studies have supported these conclusions. A school based program in Montserrat treated 95% of school children on a regular basis which caused a decline in intensity in both the treated children and the untreated population outside the school.  (Bundy et al., 1990).  In Kenya, treating only school children had almost the same impact on S. mansoni re-infection rates as a comprehensive program that sought to treat the entire population.  Population dynamic models of these data suggest that these observations can only be satisfactorily explained by the assumption that school children are the major contributor to helminth transmission (Chan & Bundy, 1997).​

Case Studies ~ deworming

Zanzibar – School-based deworming program and improvement in growth:  The Zanzibar Ministries of Health and Education implemented a school-based deworming program on Pemba Island that was evaluated by the Centre for Human Nutrition of Johns Hopkins School of Public Health.  Schoolchildren in grades one through four in twelve randomly selected schools were selected for evaluation and allocated to the control, twice-yearly or thrice-yearly treatment groups, with approximately 1,000 children in each group.  Before the study began, meetings were held at each school to inform parents of the deworming regime, the purpose of the evaluation, its risks and benefits, and alternatives to participation in the surveys.  Baseline, six month and twelve month follow-up nutrition and parasitology surveys were conducted.  All children present in school on survey days were invited to participate in each survey.  Overall, 91% of children participated in the baseline survey, and 85% of those children were assessed again at the twelve-month follow-up.  

Children were given thrice-yearly mebendazole and compared with children that received twice-yearly mebendazole and untreated children.  The evaluation found that children younger than ten gained 0.27 kg more weight and 0.13 cm more height in the twice yearly group, and 0.20 kg more weight and 0.30 cm more height in the thrice-yearly group, compared with the control group.  Children younger than ten with higher heights-for-age at baseline had higher weight and height gains in response to deworming.  In children ten and older, overall program effects on height or weight gains were not significant.  But in this age range, younger boys and significant improvements in height gain with thrice-yearly deworming, and children with higher heights-for-age had greater improvements in weight gain and deworming.

In conclusion, the evaluation provided evidence that the school-based deworming program improved the growth of schoolchildren.  The pre-post design of the evaluation, the comparison between randomly allocated program and control schools, and statistical adjustment for the differences in baseline characteristics among groups enabled the evaluators to conclude that periodic anti-helminthic treatment caused greater height and weight gains among children participating in the program (Stoltzfus et al., 1998).

Jamaica – Treatment for whipworm and mental development:  An experimental study conducted in Mandeville, south central Jamaica among schoolchildren of both sexes aged nine to twelve with moderate to heavy whipworm burden found improvement in working memory and long-term scanning and retrieval two months after treatment (Nokes et al., 1992).  One hundred and four children were selected with a moderate to heavy worm burden of T. trichiura (whipworm).  Each child assigned to the treatment group received one dose for three days of albendazole following initial cognitive testing. The control and placebo groups both received a matching placebo.   

It was observed that the functions affected by infection were related to attentiveness and appeared to involve both auditory short-term memory and the scanning and retrieval of long-term memory. This study is the first to demonstrate that moderate to heavy infection by whipworm has a detrimental and reversible effect on certain cognitive functions in children (Nokes et al., 1992).

Indonesia – Association between helminths and cognition:  A study in Java, Indonesia conducted by the Indonesia Partnership for Child Development investigated the association between helminth infection and cognitive and motor function in school-aged children.  432 children of both sexes and from two age groups: eight and nine years or eleven, twelve and thirteen years, and from 42 primary schools, participated in the study.  The study found that helminth infection, in particular hookworm infection, of school-age children is associated with lower scores on tests of cognitive function.  Children infected with hookworm scored significantly lower on tests of cognitive function compared with uninfected children (WHO, in press).

Mali –Evidence of the link between Schistosoma haematobium, school performance and attendance:  This study was carried out in two primary schools in Bamako, Mali.  The schoolchildren were mostly six to eleven years old and from areas with poor hygienic conditions and no regular supply of water or electricity.  580 children (51% female, 49% male) participated with one stool and one urine sample taken from each.  All positive cases of schistosomiasis were treated with a single dose of praziquantel and geohelminth infections were treated with a single dose of mebendazole.  Infection with S. haematobium was, by far, the most common helminth infection.  Overall, 537 children provided data on both intensity of S. haematobium infection and academic performance.  There was a significant decline in academic performance with increasing infection intensity. Data on both absenteeism from school and infection with S. haematobium were available for 466 of the children. There were significant increases in absenteeism with increasing age.  In addition, there was a significant interaction between the effect of absenteeism, gender and intensity of infection on academic performance, indicating that the reduction in academic performance with increasing intensity of infection cannot be dissociated from that of absenteeism (D. de Clercq et al., 1998).

 

3. School Health and Nutrition Services:  Micronutrient Supplements

In developing countries, growth retardation not only arises from infection but from malnutrition.  However, even in severe and prolonged cases of growth retardation malnutrition may be reversed and catch up growth may result (Mwanri et al., 2000). 

The four most important forms of global malnutrition are: iron deficiency anemia (IDA), vitamin A deficiency (VAD), protein energy malnutrition (PEM) and iodine deficiency disorders.  It has been estimated that malnutrition is associated with over half of all child deaths in developing countries (Stephenson, 1987)

All forms of global malnutrition may impact on the physical and psychological development of the school-age child.  Nokes, Van den Bosch and Bundy point out that there is strong evidence that among school-age children lower scores on tests of cognition or school achievement due to iron deficiency anemia can be improved and in some cases reversed after iron treatment (Nokes et al., 1998).  Based on eleven studies that have examined the effects of iron supplementation on the cognitive function or educational achievement of school-age children with iron deficiency or iron deficiency anemia, the authors conclude that the evidence suggests the treatment of IDA in preschool and school-age children through iron supplementation program may be beneficial and have immediate effects (Nokes et al., 1998). 

Deficiencies of micronutrients such as iron, vitamin A and iodine are a major problem in developing countries.  Micronutrient deficiencies can negatively effect mental development and learning ability of children and their susceptibility to infection.

Iron deficiency and anemia: Iron deficiency affects more people in the world than any other form of malnutrition. It is estimated that 60 million school-age children suffer from iron deficiency disorders whilst some 120 million suffer from iron deficiency anemia (IDA) . IDA results from a variety of causes, including inadequate iron intake, high physiologic demands in early childhood and pregnancy, and iron losses from parasitic infections. In developing regions of the world, the prevalence of IDA in 5-12 year-olds is estimated to be 46% with the highest rates found in Africa (49%) and South Asia (50%) (Stoltzfus et al., 1997). IDA in infants and young children is associated with significantly lower scores on psychological tests and also leads to long-term deficits in cognitive functioning (Drake et al., 2000).


Iodine: Iodine deficiency affects an estimated 1.6 billion people worldwide and an estimated 60 million school-age children. The consequences of iodine deficiency, collectively referred to as iodine deficiency disorders (IDD), include severe mental retardation, goiter, abortion, stillbirths and low birth weight and mild forms of motor and cognitive deficits.  Adolescent girls are an important target group for IDD control because of the adverse consequences on fetal development of iodine deficiency during pregnancy and because they generally have a higher prevalence of goiter than boys.


Vitamin A: Vitamin A deficiency is widely recognized as an important cause of blindness in children. Mild or sub-clinical vitamin A deficiency causes impaired immune function and, an increased risk of mortality from infectious diseases that can have an effect on school attendance and consequently academic performance. It is estimated that 85 million school-age children are at increased risk of acute respiratory and other infections because they are deficient in vitamin A (Del Rosso, 1999).  Vitamin A deficiency also affects iron metabolism so that with any iron supplements taken, subsequent improvement in iron status may be limited when vitamin A status is low. This is being increasingly recognized as a potential constraint when considering the impact of school-based iron supplementation. (Partnership for Child Development 2000)

Case Studies ~ micronutrient supplementation

  • Tanzania - Vitamin A supplements improve anemia and growth:  A study conducted in three primary schools in Bagomoyo District of Tanzania with 136 anemic children found that those children given combined vitamin A and iron supplements experienced significant increases in hemoglobin levels after three months.  Most (88%) of the children who received both vitamin A and iron were not anemic after three months of supplementation, compared with only three percent of the placebo group (Mwanri et al., 2000).
  • Jamaica – Nutritional supplementation, psychosocial stimulation, and improvements in the mental development of stunted children:  A study in Kingston, Jamaica assessed the effects of nutritional supplementation, with or without psychosocial stimulation, of growth-retarded (stunted) children aged 9-24 months.  One hundred and twenty-nine children from poor neighborhoods were randomly assigned to four groups: control, supplemented only, stimulated only, and supplemented and stimulated.  The supplement consisted of one kg milk-based formula per week for two years, and the stimulation weekly play sessions at home with a community health worker.  The children's development was assessed on the Griffiths mental development scales.  Stimulation and supplementation had significant independent beneficial effects on the children's development.  The study found that combined interventions were more effective than either alone.  These finding suggest that poor mental development in stunted children is partially attributable to under nutrition (Grantham-McGregor et al., 1991).
  • USA – Cognitive effects of iron supplementation in non-anemic iron-deficient adolescent girls:  Iron deficiency is not limited to the developing world.  In the USA, up to 25% of adolescent girls are iron deficient.  Eighty-one girls with non-anemic iron deficiency from four Baltimore high schools participated in this study.  Participants were randomly assigned oral ferrous sulphate or placebo for eight weeks.  The effect of iron treatment was assessed by questionnaires and hematological and cognitive tests, which were done before treatment started and after the intervention.  Post-intervention measures of iron status were significantly improved in the treatment group. The study found that girls who received iron performed better on a test of verbal learning and memory than girls in the control group (Bruner et al., 1996).
     

4. School Health and Nutrition Programs: Examples

Tanzania – Ushirikiano wa Kumwendeleza Mtoto Tanzania (UKUMTA) and the effect of deworming on school children: The Tanzanian Partnership for Child Development (UKUMTA) was established in 1994 with the aim of promoting the health and education of school age children in Tanzania, furthered through four main activities:

  • Large-scale operations research on treatment programs for intestinal helminths in Tanga region involving 110,000 children.
  • Developing and improving pictorial health education materials to strengthen the health education curriculum.
  • Monitoring and evaluating the effects of interventions in Tanga Region in terms of health, growth, micronutrient status and education of primary school children and the processes and costs of delivering these interventions
  • Applied research studies on the health and education of school age children including: the Makwami project which examines the effects of treating parasitic infections on the cognitive process in children and their education achievement; a study of children not enrolled in school; and a study of perceptions of pictures used in health education materials in schools.

UKUMTA is supported by four ministries: Education and Culture; Health; Community Development, Women Affairs and Children; and the Office of Local Government.  Various Tanzanian medical and educational institutions provide technical assistance to the program, with the advice of the Scientific Coordinating Centre of the Partnership for Child Development, based in the UK.

One of the main activities of UKUMTA is a large-scale demonstration school health program that delivered school health services to over 110,000 children in all 352 schools in three districts of Tanga Region.  In 1996 and 1997 the Ministry of Education, in collaboration with the Ministry of Health, coordinated the delivery of two rounds of free treatment with albendazole and praziquantel to be given to children by their teachers. 

Questionnaire Survey and Baseline Study

UKUMTA has been instrumental in the development of innovative tools and methods for school health programs. At the onset of the program, UKUMTA developed and delivered a questionnaire survey about ill health to pupils in 639 schools in Tanga Region, administered by teachers.  The data was used to select schools for the baseline survey and to examine children's self-reported health problems (such as kichocho or urinary schistosomiasis).  The children had a poor perception of their health status and almost all identified at least one health problem in the previous two weeks.

The questionnaire survey was followed by a baseline survey of 1396 children from 41 schools.  The survey found that 77% of children in Tanzania were classified as anemic and over half showed evidence of mild iodine deficiency or worse.  Most children showed evidence of chronic rather than acute under-nutrition, with 70% of children classified as stunted and 54% as underweight.  Eighty-six percent of children were infected with at least one parasitic helminth, with 63% of children infected with hookworm.

After the first round of treatment another health survey was conducted.  About 1,000 new children were examined in the three interventions districts, all who were treated.  These children were compared with another 1,000 children in the comparison districts who had not participated in the UKUMTA program.  The survey found the following:

  • Re-infection of urinary schistosomiasis was low;
  • Anemia was significantly less common in the children who had been treated with albendazole and praziquantel, and
  • There was evidence of better growth of children after treatment.

In addition to the questionnaire survey, special poles to measure height (as a proxy for weight) were adapted and used by UKUMTA as a simple and inexpensive alternative to weighing scales (too fragile and expensive for many low-income countries), in order to determine the appropriate dose of praziquantel to be delivered by teachers to treat schistosomiasis  (Hall, Nokes, Wen et al., 1999).

Burkina Faso - Save the Children (USA) and School Health Activities:   School-based health services are essential elements of Save the Children's (SC/US) School Health and Nutrition activities in more than thirteen countries in Africa, Asia, Latin America and the Middle East.  These activities may include micronutrient supplementation (vitamin A, iodine and iron), deworming for intestinal parasites and schistosomiasis, school nutrition programs, the provision of first aid kits, screening and treatment of eye infections and classroom remediation for vision and hearing impairments.

To ensure that interventions respond to local needs, SC/US and the Ministry of Health, with technical support from the Institut National de Recherche en Sante Publique in Mali, carried out a situation analysis in eight SC/US community schools in Burkina Faso's Bazega Province.  The situation analysis found that school-aged children in Bazega Province suffer from high rates of malnutrition, micronutrient deficiencies and parasitic infections, inhibiting both mental and physical development.  Based on these results, in 1999 Save the Children (USA) in collaboration with the local Ministry of Health and Ministry of Education launched a School Health and Nutrition program in 24 SC/US community schools in Bazega Province, expanding to another 34 formal schools.  The program now reaches nearly 15,000 schoolchildren and is set to expand to other provinces.

The program's school-based health services include annual treatment for intestinal parasites with albendazole and praziquantel for schistosomes and the provision of vitamin A and iodine.  In addition, school-based health services are supported by skills based health education and the provision of both latrines and safe drinking water.

One year after the start of the program an evaluation conducted in five community schools found a significant impact on the prevalence of malnutrition, anemia, worm and schistosome infection, as well as a substantial improvement in school performance and attendance.  The prevalence of malnutrition and anemia dropped by one-third, schistosomiasis infection fell by one-half, overall worm infection by 15%, and night-blindness decreased from 5.9% to 0.7%.  In addition, there was a 30% improvement in end of year exam results and 20% improvement in school attendance, with both improvements sustained in the second year of the program. 

Discussions conducted by SC/US with both parents and children have found that school-based health services, particularly micronutrient supplementation and deworming, are seen as a substantial benefit to school and consequently improve attendance and enrolment.  As one teacher put it: "Now parents want their children to go to school because at school their health is taken care of."  

 5. The way forward

School-based health and nutrition services are more likely to benefit the health and nutritional status of schoolchildren when delivered in the context of  THE FRESH framework.   School-based health and nutrition services are an integral part of an effective school health and nutrition programme as called for in the  FRESH framework and should exist alongside health-related school policies, the provision of safe water and sanitation and skills based health education.  The provision of safe water, sanitation and skills based health education, including hygiene education is particularly important, as these are the long-term solutions to combating helminth infection. 

Based on the school health experiences of the FRESH partner agencies, school health and nutrition programmes are most likely to be planned and implemented effectively through effective partnerships and collaboration between health and education workers, teacher, parents, students and members of the community..  In addition, the delivery of school-based health and nutritional services  must be simple, safe and familiar, and address problems that are both prevalent and recognized as important within the community. 

References

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