Nutrition, anaemia, geohelminth infection and school achievement in rural Jamaican primary school children

Iron Status, Anemia, and Iron Interventions and Their Associations with Cognitive and Academic Performance in Adolescents: A Systematic Review

In adolescents, iron-deficiency anemia is the leading cause of disability-adjusted life years lost. The World Health Organization recommends delivering iron supplementation through school-based platforms, requiring partnerships with the education sector. This anemia-reduction intervention is valued for the perceived benefits of improved learning and school performance. This article aims to systematically review the available evidence on the relationship between iron status and anemia and impacts of iron interventions on cognitive and academic performance in adolescents. Fifty studies were included: n = 26 cross-sectional and n = 24 iron-containing interventions. Our review suggests that iron status and anemia may be associated with academic performance in some contexts and that iron supplementation during adolescence may improve school performance, attention, and concentration. However, nearly all supplementation trials were judged to have moderate or high risk of bias. We did not find evidence suggesting that iron status and anemia influenced or were associated with attention, intelligence, nor memory in adolescents. Further, iron supplementation did not improve memory and recall or intelligence. Overall, more high-quality research is needed to guide programmers and policy makers to understand the relationships between anemia and educational performance and the potential impacts of iron interventions, which effectively reduce anemia, on adolescents’ learning and school performance.

Prevalence, intensity and associated risk factors of soil-transmitted helminth and schistosome infections in Kenya: Impact assessment after five rounds of mass drug administration in Kenya

Background

In Kenya, over five million school age children (SAC) are estimated to be at risk of parasitic worms causing soil-transmitted helminthiasis (STH) and schistosomiasis. As such, the Government of Kenya launched a National School Based Deworming (NSBD) program in 2012 targeting the at-risk SAC living in endemic regions, with the aim of reducing infections prevalence to a level where they no longer constitute a public health problem. The impact of the program has been consistently monitored from 2012 to 2017 through a robust and extensive monitoring and evaluation (M&E) program. The aim of the current study was to evaluate the parasitological outcomes and additionally investigate water, sanitation and hygiene (WASH) related factors associated with infection prevalence after five rounds of mass drug administration (MDA), to inform the program’s next steps.

Materials and methods

We utilized a cross-sectional design in a representative, stratified, two-stage sample of school children across six regions in Kenya. A sample size of 100 schools with approximately 108 children per school was purposively selected based on the Year 5 STH infection endemicity prior to the survey. Stool samples were examined for the presence of STH and Schistosoma mansoni eggs using double-slide Kato-Katz technique, urine samples were processed using urine filtration technique for the presence of S. haematobium eggs. Survey questionnaires were administered to all the participating children to collect information on their demographic and individual, household and school level WASH characteristics.

Principal findings

Overall, STH prevalence was 12.9% (95%CI: 10.4–16.1) with species prevalence of 9.7% (95%CI: 7.5–12.6) for Ascaris lumbricoides, 3.6% (95%CI: 2.2–5.8) for Trichuris trichiura and 1.0% (95%CI: 0.6–1.5) for hookworm. S. mansoni prevalence was 2.2% (95%CI: 1.2–4.3) and S. haematobium prevalence was 0.3% (95%CI: 0.1–1.0). All the infections showed significant prevalence reductions when compared with the baseline prevalence, except S. mansoni. From multivariable analysis, increased odds of any STH infections were associated with not wearing shoes, adjusted odds ratio (aOR) = 1.36 (95%CI: 1.09–1.69); p = 0.007; high number of household members, aOR = 1.21 (95%CI: 1.04–1.41); p = 0.015; and school absenteeism of more than two days, aOR = 1.33 (95%CI: 1.01–1.80); p = 0.045. Further, children below five years had up to four times higher odds of getting STH infections, aOR = 4.68 (95%CI: 1.49–14.73); p = 0.008. However, no significant factors were identified for schistosomiasis, probably due to low prevalence levels affecting performance of statistical analysis.

Conclusions

After five rounds of MDA, the program shows low prevalence of STH and schistosomiasis, however, not to a level where the infections are not a public health problem. With considerable inter-county infection prevalence heterogeneity, the program should adopt future MDA frequencies based on the county’s infection prevalence status. Further, the program should encourage interventions aimed at improving coverage among preschool age children and improving WASH practices as long-term infection control strategies.

This paper presents the findings of an evaluation survey conducted in Year 6 of the Kenya National School-Based Deworming (NSBD) Program, following five years (2012–2017) of prior baseline and subsequent impact monitoring. The survey was conducted in 20 counties, covering six regions in Kenya. The survey showed continued and considerable reductions in prevalence over time, with most marked decline for hookworm, followed by Ascaris lumbricoides. Overall, the mass drug administration (MDA) program has driven both STH and schistosomiasis prevalence to relatively low levels, however not to a point where they no longer constitute a public health problem in Kenya. For these neglected tropical diseases (NTDs), and STH in particular, there are relatively few published examples of programmatic impact assessments enabling refined decisions regarding helminth control strategies. Kenya’s experiences in implementing, monitoring, and evaluating a high-coverage NSBD program are a continuing and increasingly important success story for the country, which provides learnings of importance for the international community.

Caregiver Strengths, Attitudes, and Concerns About Reading and Child Development in the Dominican Republic

Background. Parents' beliefs about and engagement in reading aloud to young children and other positive parenting practices have been associated with early childhood development (ECD) and later achievement. Aim. This exploratory study sought to assess parental attitudes and self-reported practices regarding ECD in a rural, low-income community in the Dominican Republic with many risk factors for ECD delays, including high rates of poverty, iron-deficiency anemia, and malnutrition. Methods. We used the Parent Reading Belief Inventory and open-ended questions to evaluate parental beliefs regarding reading, self-efficacy in promoting child development, current positive parenting practices, and parents' concerns about the development of their 0- to 5-year-old children in Consuelo, Dominican Republic. We explored associations between demographic factors and strength of positive parenting beliefs and practices. Results. Overall participants had positive attitudes toward reading and their own importance in promoting their children's development. Participants with at least some high school education had significantly higher Parent Reading Belief Inventory scores (P = .03) than those with less formal education. Participants reported frequently singing, talking, and playing with their children, but less frequently reading with them. Few participants had access to reading materials for young children. Parental interest in programs to support ECD was high. Parents raised concerns about their children's behavior, personal and educational attainment, and early literacy. Conclusion. Children whose parents have less formal education may benefit most from interventions to promote beliefs and practices likely to improve ECD. In this community, there is high interest in learning more about ECD.

Hutton Z, Fattore G, Sabatier M, Detzel P. Reducing the burden of iron deficiency anemia in Cote D'Ivoire through fortification

BACKGROUND

Iron deficiency anemia (IDA) is highly prevalent in the Cote d'Ivoire and has severe health and economic consequences. In this paper, we apply a health economic model to quantify the burden of IDA, and the contribution of nationwide mandatory iron fortification of wheat flour and voluntary iron fortification of condiments to the reduction of this burden.

METHODS

The analysis for the population from 6 months to 64 years builds on published reviews and publicly available datasets and is stratified by age-groups and socioeconomic strata using comparative risk assessment model.

RESULTS

Without the impact of these fortification strategies, the annual burden of IDA is estimated at 242,100 disability adjusted life years (DALYs) and 978.1 million USD. Wheat flour and condiment fortification contributed to a reduction of the IDA burden by approximately 5% each.

CONCLUSION

In places with high prevalence of malaria and other infectious diseases, such as the Côte D'Ivoire, food fortification as a nutritional intervention should be accompanied with infectious disease prevention and control. The findings of this study provide additional input for policy makers about the magnitude of the impact and can support the conception of future fortification strategies.

Nutrients Essential for Cognitive Function Are Typical Problem Nutrients in the Diets of Myanmar Primary School Children: Findings of a Linear Programming Analysis

BACKGROUND

Good cognitive function is important for school-age children. Although essential fatty acids play a main role in cognitive functions, their intakes are assumed as inadequate among developing countries including Myanmar. However, there is still lack of evidence to show whether they are problem nutrients.

OBJECTIVE

This study aimed to determine the problem nutrients in the diets of Myanmar primary schoolchildren and to formulate food-based recommendations (FBR) to optimize the intake of these micronutrients.

METHODS

A cross-sectional study was conducted at 3 primary schools in Nyaungdon Township of Myanmar. A 1-week dietary intake assessment was done on 7- to 9-year-old (n = 100) primary schoolchildren. A linear programming approach using the World Health Organization Optifood software was used to assess the nutrient intake and develop FBRs.

RESULTS

The prevalence of stunted growth, wasting, and being underweight in the students were 28%, 18%, and 28%, respectively. The intake of calcium, vitamin B₁, folate, iron, omega-3 fatty acids, eicosapentaenoic acid, and docosahexaenoic acid was insufficient. Locally available nutrient-dense foods that include water spinach, carp fish, duck egg, garden pea, and shrimp were selected to develop FBR to increase the intake of problem nutrients.

CONCLUSION

The linear programming analysis showed that the primary schoolchildren have difficulty meeting nutrient recommendations given locally available foods, especially iron and essential fatty acids which are important for cognitive performance of schoolchildren.

Bayesian Methods for Exposure Misclassification Adjustment in a Mediation Analysis: Hemoglobin and Malnutrition in the Association Between Ascaris and IQ

BACKGROUND

Soil-transmitted helminth infections have been found to be associated with child development. The objective was to investigate hemoglobin levels and malnutrition as mediators of the association between Ascaris infection and intelligence quotient (IQ) scores in children.

METHODS

We conducted a longitudinal cohort study in Iquitos, Peru, between September 2011 and July 2016. A total of 1760 children were recruited at 1 year of age and followed up annually to 5 years. We measured Ascaris infection and malnutrition at each study visit, and hemoglobin levels were measured as of age 3. The exposure was defined as the number of detected Ascaris infections between age 1 and 5. We measured IQ scores at age 5 and used Bayesian models to correct exposure misclassification.

RESULTS

We included a sample of 781 children in the analysis. In results adjusted for Ascaris misclassification, mean hemoglobin levels mediated the association between Ascaris infection and IQ scores. The natural direct effects (not mediated by hemoglobin) (95% CrI) and natural indirect effects (mediated by hemoglobin) (95% CrI) were compared with no or one infection: -0.9 (-4.6, 2.8) and -4.3 (-6.9, -1.6) for the effect of two infections; -1.4 (-3.8, 1.0) and -1.2 (-2.0, -0.4) for three infections; and -0.4 (-3.2, 2.4) and -2.7 (-4.3, -1.0) for four or five infections.

CONCLUSION

Our results are consistent with the hypothesis that hemoglobin levels mediate the association between Ascaris infection and IQ scores. Additional research investigating the effect of including iron supplements in STH control programs is warranted.

The effect of cumulative soil-transmitted helminth infections over time on child development: a 4-year longitudinal cohort study in preschool children using Bayesian methods to adjust for exposure misclassification

Background

Limited research has documented an association between soil-transmitted helminth (STH) infections and child development. This has recently been identified as an important knowledge gap.

Methods

A longitudinal cohort study was conducted in Iquitos, Peru, between September 2011 and July 2016. A cohort of 880 children, recruited at 1 year of age, was followed up to 5 years. STH infection was measured annually and child development was measured with the Wechsler Preschool and Primary Scale of Intelligence III (WPPSI-III) at 5 years. Linear-regression models were used to investigate the effect of the number of detected STH infections between 1 and 5 years of age on WPPSI-III scores at 5 years of age. Bayesian latent class analysis was used to adjust for exposure misclassification.

Results

A total of 781 (88.8%) children were included in the analysis. In multivariable analysis, adjusted for STH misclassification, increasing numbers of Ascaris, Trichuris, hookworm and any STH infections were associated with lower WPPSI-III scores. Among the largest observed effects were those for the effect of Ascaris infection on verbal IQ scores [difference in IQ (95% CrI) for two, three, and four or five detected infections compared with zero or one infection: -8.27 (-13.85, -3.10), -6.69 (-12.05, -2.05) and -5.06 (-10.75, 0.05), respectively]. Misclassification of STH infection generally led to a bias towards the null.

Conclusions

These results document an association between STH infection and child development. The results highlight the importance of adjusting for STH misclassification; however, future research is needed to accurately determine the sensitivity of STH diagnostic techniques. STH control in preschool children may contribute to lowering the disease burden associated with poor child development.

A longitudinal cohort study of soil-transmitted helminth infections during the second year of life and associations with reduced long-term cognitive and verbal abilities

BACKGROUND

Soil-transmitted helminth (STH) infection leads to malnutrition and anemia, and has been linked to impaired child development. Previous research on this topic is limited and mostly conducted in school-age children. The goal of this study was to determine the effect of the number of detected STH infections between one and two years of age on subsequent cognitive and verbal abilities, in a cohort of preschool children.

METHODOLOGY/PRINCIPAL FINDINGS

A longitudinal cohort study was conducted in 880 children in Iquitos, Peru between September 2011 and July 2016. Children were recruited at one year of age and followed up at 18 months and then annually between two and five years of age. STH infection was measured with the Kato-Katz technique or the direct smear technique. Child development was measured with the Bayley Scales of Infant and Toddler Development-III at the one to three-year visits and with the Wechsler Preschool and Primary Scale of Intelligence-III at the four and five-year visits. Hierarchical multivariable linear regression models were used to account for the repeated outcome measures for each child and Bayesian latent class analysis was used to adjust for STH misclassification. Children found infected with any STH infection between one and two years of age had lower cognitive scores between two and five years of age (between group score differences (95% credible intervals) for infected once, and infected two or three times, compared to never infected: -4.31 (-10.64, -0.14) and -3.70 (-10.11, -0.11), respectively). Similar results were found for Ascaris infection and for verbal scores.

CONCLUSIONS/SIGNIFICANCE

An association was found between having been infected with Ascaris or any STH between one and two years of age and lower cognitive and verbal abilities later in childhood. These results suggest that targeting children for STH control as of one year of age is particularly important.

Soil-transmitted helminth infection, loss of education and cognitive impairment in school-aged children: A systematic review and meta-analysis

BACKGROUND

Evidence of an adverse influence of soil transmitted helminth (STH) infections on cognitive function and educational loss is equivocal. Prior meta-analyses have focused on randomized controlled trials only and have not sufficiently explored the potential for disparate influence of STH infection by cognitive domain. We re-examine the hypothesis that STH infection is associated with cognitive deficit and educational loss using data from all primary epidemiologic studies published between 1992 and 2016.

METHODS

Medline, Biosis and Web of Science were searched for original studies published in the English language. Cognitive function was defined in four domains (learning, memory, reaction time and innate intelligence) and educational loss in two domains (attendance and scholastic achievement). Pooled effect across studies were calculated as standardized mean differences (SMD) to compare cognitive and educational measures for STH infected/non-dewormed children versus STH uninfected /dewormed children using Review Manager 5.3. Sub-group analyses were implemented by study design, risk of bias (ROB) and co-prevalence of Schistosoma species infection. Influential studies were excluded in sensitivity analysis to examine stability of pooled estimates.

FINDINGS

We included 36 studies of 12,920 children. STH infected/non-dewormed children had small to moderate deficits in three domains-learning, memory and intelligence (SMD: -0.44 to -0.27, P<0.01-0.03) compared to STH-uninfected/dewormed children. There were no differences by infection/treatment status for reaction time, school attendance and scholastic achievement (SMD: -0.26 to -0.16, P = 0.06-0.19). Heterogeneity of the pooled effects in all six domains was high (P<0.01; I2 = 66-99%). Application of outlier treatment reduced heterogeneity in learning domain (P = 0.12; I2 = 33%) and strengthened STH-related associations in all domains but intelligence (SMD: -0.20, P = 0.09). Results varied by study design and ROB. Among experimental intervention studies, there was no association between STH treatment and educational loss/performance in tests of memory, reaction time and innate intelligence (SMD: -0.27 to 0.17, P = 0.18-0.69). Infection-related deficits in learning persisted within design/ROB levels (SMD: -0.37 to -52, P<0.01) except for pre-vs post intervention design (n = 3 studies, SMD = -0.43, P = 0.47). Deficits in memory, reaction time and innate intelligence persisted within observational studies (SMD: -0.23 to -0.38, all P<0.01) and high ROB strata (SMD:-0.37 to -0.83, P = 0.07 to <0.01). Further, in Schistosoma infection co-prevalent settings, associations were generally stronger and statistically robust for STH-related deficits in learning, memory and reaction time tests(SMD:-0.36 to -0.55, P = 0.003-0.02). STH-related deficits in school attendance and scholastic achievement was noted in low (SMD:-0.57, P = 0.05) and high ROB strata respectively.

INTERPRETATION

We provide evidence of superior performance in five of six educational and cognitive domains assessed for STH uninfected/dewormed versus STH infected/not-dewormed school-aged children from helminth endemic regions. Cautious interpretation is warranted due to high ROB in some of the primary literature and high between study variability in most domains. Notwithstanding, this synthesis provides empirical support for a cognitive and educational benefit of deworming. The benefit of deworming will be enhanced by strategically employing, integrated interventions. Thus, multi-pronged inter-sectoral strategies that holistically address the environmental and structural roots of child cognitive impairment and educational loss in the developing world may be needed to fully realize the benefit of mass deworming programs.

Anemia in pregnancy in Western Jamaica

BACKGROUND

Anemia is one of the most prevalent problems in pregnancy. In 2011, 29.9% of all pregnant women in Jamaica were diagnosed with anemia.

OBJECTIVE

The objective of this study was to determine the prevalence and predictors of anemia in pregnancy in Western Jamaica.

METHODS

A cross-sectional study was conducted among 293 mothers attending post-natal clinics in Western Jamaica. A questionnaire was administered to the mothers, and an abstraction form was used to collect clinical data from the mothers' records.

RESULTS

The prevalence of anemia among the women was 37.6%. Younger mothers (aged 18-24 years) were more likely to be anemic compared to those ≥35 years (odds ratio [OR]: 3.44, 95% CI: 1.07-11.06). Mothers who reported not always washing their hands after using the toilet were almost 10 times more likely to be anemic (OR: 9.7, 95% CI: 1.72-54.78) compared to those who reported always washing their hands. Mothers who attended a public facility for antenatal care were 2.3 times more likely to be anemic (OR: 2.31, 95% CI: 1.03-5.18) compared to those who obtained care at a private facility, and mothers who reported being told that they were anemic by a health care provider (HCP) were almost six times more likely to be anemic compared with those who were not told (OR: 5.58, 95% CI: 1.73-17.93).

CONCLUSION

The results of the study indicate that early identification and treatment of anemia, especially among younger pregnant women, should be a priority. HCP should ensure that women understand the need to be cured of their anemia and to adhere to preventive hygienic practices.

Measuring the Effect of Soil-Transmitted Helminth Infections on Cognitive Function in Children: Systematic Review and Critical Appraisal of Evidence

Recently the role of soil-transmitted helminth (STH) infections in children's cognitive developmental impairment has been under scrutiny. We conducted a systematic review of the evidence for associations between STH infections and cognitive function of children using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. We aimed to identify the domains of cognitive function in three age strata (<24months, 24-59months and ≥60months) and critically appraise the general design protocol of the studies, with a focus on the cognitive function measurement tools used. A total of 42 papers fulfilled the inclusion criteria, including 10 studies from a recent Cochrane review. Our findings demonstrate variation in tested domains, lack of consistency in the use of measurement tools and analysis of results. Cognitive function measures in children aged under 59months have been mainly limited to domains of gross motor, fine motor and language skills, whereas in children aged 60months and above most studies tested domains such as memory and processing speed. Even within the same age group the results on the association between STH infections and measures of cognitive development were often conflicting. The current study highlights the need for methodological consensus in the use of measurement tools and data analysis protocols if the effect of STH infections on cognitive function domains in children is to be correctly established. This will be an imperative next step to generate conclusive evidence of the role of STH infections in cognitive development in children.

Malaria, anaemia and under-nutrition: three frequently co-existing conditions among preschool children in rural Rwanda

Background

Malaria, anaemia and under-nutrition are three highly prevalent and frequently co-existing diseases that cause significant morbidity and mortality particularly among children aged less than 5 years. Currently, there is paucity of conclusive studies on the burden of and associations between malaria, anaemia and under-nutrition in Rwanda and comparable sub-Saharan and thus, this study measured the prevalence of malaria parasitaemia, anaemia and under-nutrition among preschool age children in a rural Rwandan setting and evaluated for interactions between and risk determinants for these three conditions.

Methods

A cross-sectional household (HH) survey involving children aged 6–59 months was conducted. Data on malaria parasitaemia, haemoglobin densities, anthropometry, demographics, socioeconomic status (SES) and malaria prevention knowledge and practices were collected.

Results

The prevalences of malaria parasitaemia and anaemia were 5.9 and 7.0 %, respectively, whilst the prevalence of stunting was 41.3 %. Malaria parasitaemia risk differed by age groups with odds ratio (OR) = 2.53; P = 0.04 for age group 24–35 months, OR = 3.5; P = 0.037 for age group 36–47 months, and OR = 3.03; P = 0.014 for age group 48–60 months, whilst a reduced risk was found among children living in high SES HHs (OR = 0.37; P = 0.029). Risk of anaemia was high among children aged ≥12 months, those with malaria parasitaemia (OR = 3.86; P ≤ 0.0001) and children living in HHs of lower SES. Overall, under-nutrition was not associated with malaria parasitaemia. Underweight was higher among males (OR = 1.444; P = 0.019) and children with anaemia (OR = 1.98; P = 0.004).

Conclusions

In this study group, four in 10 and one in 10 children were found stunted and underweight, respectively, in an area of low malaria transmission. Under-nutrition was not associated with malaria risk. While the high prevalence of stunting requires urgent response, reductions in malaria parasitaemia and anaemia rates may require, in addition to scaled-up use of insecticide-treated bed nets and indoor residual insecticide spraying, improvements in HH SES and better housing to reduce risk of malaria.

Effects of a post-deworming health hygiene education intervention on absenteeism in school-age children of the Peruvian Amazon

Soil-transmitted helminth (STH) infections are a leading cause of disability and disease burden in school-age children of worm-endemic regions. Their effect on school absenteeism, however, remains unclear. The World Health Organization currently recommends delivering mass deworming and health hygiene education through school-based programs, in an effort to control STH-related morbidity. In this cluster-RCT, the impact of a health hygiene education intervention on absenteeism was measured. From April to June 2010, all Grade 5 students at 18 schools in a worm-endemic region of the Peruvian Amazon were dewormed. Immediately following deworming, nine schools were randomly assigned to the intervention arm of the trial using a matched-pair design. The Grade 5 students attending intervention schools (N = 517) received four months of health hygiene education aimed at increasing knowledge of STH prevention. Grade 5 students from the other nine schools (N = 571) served as controls. Absenteeism was measured daily through teachers' attendance logs. After four months of follow-up, overall absenteeism rates at intervention and control schools were not statistically significantly different. However, post-trial non-randomized analyses have shown that students with moderate-to-heavy Ascaris infections and light hookworm infections four months after deworming had, respectively, missed 2.4% (95% CI: 0.1%, 4.7%) and 4.6% (95% CI: 1.9%, 7.4%) more schooldays during the follow-up period than their uninfected counterparts. These results provide empirical evidence of a direct effect of STH infections on absenteeism in school-age children.

Animal source foods have a positive impact on the primary school test scores of Kenyan schoolchildren in a cluster-randomised, controlled feeding intervention trial

Micronutrient deficiencies and suboptimal energy intake are widespread in rural Kenya, with detrimental effects on child growth and development. Sporadic school feeding programmes rarely include animal source foods (ASF). In the present study, a cluster-randomised feeding trial was undertaken to determine the impact of snacks containing ASF on district-wide, end-term standardised school test scores and nutrient intake. A total of twelve primary schools were randomly assigned to one of three isoenergetic feeding groups (a local plant-based stew (githeri) with meat, githeri plus whole milk or githeri with added oil) or a control group receiving no intervention feeding. After the initial term that served as baseline, children were fed at school for five consecutive terms over two school years from 1999 to 2001. Longitudinal analysis was used controlling for average energy intake, school attendance, and baseline socio-economic status, age, sex and maternal literacy. Children in the Meat group showed significantly greater improvements in test scores than those in all the other groups, and the Milk group showed significantly greater improvements in test scores than the Plain Githeri (githeri+oil) and Control groups. Compared with the Control group, the Meat group showed significant improvements in test scores in Arithmetic, English, Kiembu, Kiswahili and Geography. The Milk group showed significant improvements compared with the Control group in test scores in English, Kiswahili, Geography and Science. Folate, Fe, available Fe, energy per body weight, vitamin B₁₂, Zn and riboflavin intake were significant contributors to the change in test scores. The greater improvements in test scores of children receiving ASF indicate improved academic performance, which can result in greater academic achievement.

Utilization of a mobile medical van for delivering pediatric care in the bateys of the Dominican Republic

Background

Bateys are impoverished areas of housing for migrant Haitian sugar cane workers in the Dominican Republic (DR). In these regions, preventative health care is almost non-existent, public service accessibility is limited, and geographic isolation prevents utilization of care even by those families with resources. Consequently, the development of a viable mobile system is vital to the delivery of acute and preventative health care in this region.

Aims

This study evaluated an existing mobile medical system. The primary goal was to describe the population served, diseases treated, and resources utilized. A secondary goal was to determine qualitatively an optimal infrastructure for sustainable health care delivery within the bateys.

Methods

Information on basic demographic data, diagnosis, chronicity of disease, and medications dispensed was collected on all pediatric patients seen in conjunction with an existing mobile medical system over a 3-month period in the DR. Health statistics for the region were collected and interviews were conducted with health care workers (HCWs) and community members on existing and optimal health care infrastructure.

Results

Five hundred eighty-four pediatric patients were evaluated and treated. Median age was 5 years (range 2 weeks to 20 years), and 53.7% of patients seen were 5 years of age or younger. The mean number of complaints per patient was 2.8 (range 0 to 6). Thirty-six percent (373) of all diagnoses were for acute complaints, and 64% (657) were chronic medical problems. The most common pediatric illnesses diagnosed clinically were gastrointestinal parasitic infection (56.6%), skin/fungal infection (46.2%), upper respiratory tract infections (URIs) (22.8%), previously undiagnosed asthma and allergies (8.2%), and symptomatic anemia (7.2%). Thirty HCWs and community members were interviewed, and all cited the need for similar resources: a community clinic and hospital referral site, health promoters within each community, and the initiation of pediatric training for community HCWs.

Conclusion

A mobile medical system is a sustainable, efficient mechanism for delivering acute and preventive care in the Haitian bateys of the Dominican Republic. The majority of patients served were 8 years of age or younger with multiple presenting symptoms. A pediatric protocol for identifying the most appropriate drugs and supplies for mobile units in the DR can be created based upon diseases evaluated. Qualitative data from HCWs and community members identified the need for an integrative health care delivery infrastructure and community health promoters versed in pediatric care who can aid in education of batey members and monitor chronic and acute illnesses. We are planning follow-up visits to implement these programs.

Experiences of violence and deficits in academic achievement among urban primary school children in Jamaica

OBJECTIVE

The aim of this study was to examine the relationship between children's experiences of three different types of violence and academic achievement among primary school children in Kingston, Jamaica.

METHODS

A cross-sectional study of 1300 children in grade 5 [mean (S.D.) age: 11 (0.5) years] from 29 government primary schools in urban areas of Kingston and St. Andrew, Jamaica, was conducted. Academic achievement (mathematics, reading, and spelling) was assessed using the Wide Range Achievement Test. Children's experiences of three types of violence - exposure to aggression among peers at school, physical punishment at school, and exposure to community violence - were assessed by self-report using an interviewer administered questionnaire.

RESULTS

Fifty-eight percent of the children experienced moderate or high levels of all three types of violence. Boys had poorer academic achievement and experienced higher levels of aggression among peers and physical punishment at school than girls. Children's experiences of the three types of violence were independently associated with all three indices of academic achievement. There was a dose-response relationship between children's experiences of violence and academic achievement with children experiencing higher levels of violence having the poorest academic achievement and children experiencing moderate levels having poorer achievement than those experiencing little or none.

CONCLUSIONS

Exposure to three different types of violence was independently associated with poor school achievement among children attending government, urban schools in Jamaica. Programs are needed in schools to reduce the levels of aggression among students and the use of physical punishment by teachers and to provide support for children exposed to community violence.

PRACTICE IMPLICATIONS

Children in Jamaica and the wider Caribbean experience significant amounts of violence in their homes, communities, and schools. In this study, we demonstrate a dose-response relationship between primary school children's experiences of three different types of violence and their academic achievement. The study points to the need for validated violence prevention programs to be introduced in Jamaican primary schools. Such programs need to train teachers in appropriate classroom management and discipline strategies and to promote children's social and emotional competence and prevent aggression.

Gastro-intestinal symptoms associated with intense Schistosoma mansoni infection affect class-attentiveness of schoolchildren in Ethiopia

OBJECTIVE

To assess effect of subtle morbidities related to Schistosomiasis mansoni on class-attentiveness of schoolchildren.

METHODS

A cross-sectional study was undertaken involving 568 schoolchildren (mean age 13.4 years; 333 from Schistosoma mansoni endemic villages (Sille and Worke-Mado) and 235 from the non-endemic town Sheno. A questionnaire on signs and symptoms of ill-health was administered to all study subjects. In addition, parasitological and nutritional anthropometric data were collected. All study subjects from S. mansoni endemic areas were treated with praziquantel and albendazol while children from the non-endemic town were only treated with albendazol.FindingsPrevalence of S. mansoni infection was 95% in Sille and 90.6% in Worke-Mado. Overall, among schoolchildren from S. mansoni endemic areas, 36.3% were under-nourished; 66.4% reported easy fatigue/listlessness; 61.3% had abdominal cramps with bloody-mucoid stools, and 17.7% reported to have severe and frequent abdominal cramps which distracted their class-attentiveness. The latter two symptoms were significantly associated with intensity of S. mansoni infection. Among schoolchildren from the non-endemic town Sheno, only 8.9% were under-nourished, 20% reported infrequent abdominal cramps and none had symptoms that were severe enough to affect class-attentiveness.

CONCLUSION

Symptoms associated with intense S. mansoni infection may negatively affect class-attentiveness of schoolchildren which may have important implications on their overall educational achievements. Further detailed intervention-based prospective studies are recommended to validate these findings which, if confirmed, could further justify school-age targeted praziquantel-based control of schistosomiasis.

Genetic haplotypes of Th-2 immune signalling link allergy to enhanced protection to parasitic worms

Parasitic worm infection, allergy and asthma involve increased IgE production, eosinophil activity, mucus secretion and smooth muscle reactivity, effected through Th-2 immune signalling. These pathological features of allergic disorder, common in developed countries, appear to be protective features in resistance to parasitic worm infections prevalent in many developing countries. We investigated how genetic variation in the Th-2 signalling transduction molecule STAT6 relates to these clinical disorders, using immune phenotyping by serum IgE levels and haplotyping nine STAT6 genetic variants in a rural Chinese population, where Ascaris infection is prevalent, and an urban UK population where Ascaris is largely unknown but asthma and allergy are prevalent. We show for the first time that STAT6 haplotypes relate clearly to IgE levels, allergy and worm burden. The haplotypes segregated into two groups: those with raised IgE/low worm burden tended to have increased risk of allergic disorder, whereas low IgE/high worm burden tended to have a reduced risk of allergies. By estimating the mean worm burden for each haplotype in China and the relative risk of asthma for the matching haplotype in the UK, we draw a cross-population comparison and show a negative correlation between worm burden and expected risk of asthma. These data imply that the origin of common up-regulating variants of Th-2 signalling, involving STAT6, promotes asthma and allergy in developed countries, whereas in developing countries it protects against parasitic worm infections. Selective evolutionary mechanisms, driven by parasitic worm infection, may underlie the genetic contribution to risk of allergy and asthma in humans.

Developmental potential in the first 5 years for children in developing countries

Many children younger than 5 years in developing countries are exposed to multiple risks, including poverty, malnutrition, poor health, and unstimulating home environments, which detrimentally affect their cognitive, motor, and social-emotional development. There are few national statistics on the development of young children in developing countries. We therefore identified two factors with available worldwide data--the prevalence of early childhood stunting and the number of people living in absolute poverty--to use as indicators of poor development. We show that both indicators are closely associated with poor cognitive and educational performance in children and use them to estimate that over 200 million children under 5 years are not fulfilling their developmental potential. Most of these children live in south Asia and sub-Saharan Africa. These disadvantaged children are likely to do poorly in school and subsequently have low incomes, high fertility, and provide poor care for their children, thus contributing to the intergenerational transmission of poverty.

Early childhood diarrhea predicts impaired school performance

OBJECTIVE

Diarrhea is a leading cause of mortality worldwide; however, its long-term morbidity is poorly understood. Recently, early childhood diarrhea (ECD) has been associated with impaired physical fitness, growth and cognitive function 6 to 9 years later. We studied the effects of ECD on school functioning in a shantytown in northeastern Brazil.

DESIGN

We administered 77 educational surveys. Complete diarrhea surveillance (ie, >90%) in the first 2 years of life and demographic and anthropometric information were available for 73 children. Age at starting school was calculated for 62 children, whereas age appropriateness for the current grade (AFG) was calculated for all 73 children who were >6 years old. Stepwise regression was used to examine the independent effect of ECD on school functioning after controlling for socioeconomic factors, maternal education, breast feeding, growth and cognitive functioning.

RESULTS

ECD correlated with age at starting school (r = 0.55, P = 0.0005) and remained a significant predictor even after controlling for family demographics, days of breast feeding, early growth and TONI-3 test of nonverbal intelligence. This was true despite significant correlations of ECD with growth shortfalls and impaired cognitive functioning. ECD also correlated with AFG (r = 0.38, P = 0.001). Only TONI-3 test scores explained this association, suggesting that ECD may hinder school performance, but only in part school readiness, by impairing cognitive function as measured by performance on the TONI-3 nonverbal intelligence test.

CONCLUSIONS

These findings document effects of early childhood diarrhea on later school readiness and performance and hence potential long-term human and economic costs of ECD, which warrant further attention and far greater investment for the control of ECD and its consequences.

Chronic health conditions and student performance at school

To review the state of research on the association between common chronic health conditions and academic outcomes, the authors reviewed published studies investigating the association of school attendance, cognitive ability, and achievement with a number of chronic diseases. Tables with brief descriptions of each study's research methods and outcomes are included. Research reveals evidence that diabetes, sickle cell anemia, and epilepsy affect student achievement and ability. Levels of academic deficiency and specific areas of cognitive impairment are not as well understood. Many chronic conditions are not well researched. Suggestions for further research and recommendations for educators and health practitioners are provided.

Environmental influences on helminthiasis and nutritional status among Pacific schoolchildren

This paper describes a study undertaken to: (1) determine the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm infections and nutritional status among Pacific Island school children; (2) identify factors influencing helminthiasis; (3) identify interventions to improve school health. A total of 3,683 children aged 5-12 years attending 27 primary schools in 13 Pacific Island countries were surveyed along with school environmental data. Stool samples were collected from 1996 children (54.2%) and analysed for ova and helminths. Total prevalence of helminthiasis was 32.8%. Anaemia prevalence was 12.4%. Children with helminthiasis and anaemia were found to be 8.7 times more likely to be stunted and 4.3 times more likely to be underweight than non-anaemic and non-infected children. Four significant environmental influences on helminthiasis were identified: (1) an inadequate water supply; (2); availability of a school canteen; (3) regular water/sanitation maintenance regimes; and (4) overcrowded classrooms. Helminthiasis was found to be strongly associated with anaemia, stunting and underweight and environmental influences identified. Although mass anti-helminthic drug administrations (MDA) have been taking place, reinfection is common as drug therapy alone is not enough. Programme effectiveness depends upon upgrading school environments to include an adequate water supply, controlled food preparation/provision, well-maintained water/sanitation facilities and class sizes of 30 students or less.

Nutrition status, education participation, and school achievement among Kenyan middle-school children

OBJECTIVE

The intervening effects of nutrition status on school attendance rates among Kenyan middle school pupils were assessed. The study also examined the effects of nutrition status on primary school achievement scores for the eighth-grade class of 1997.

METHODS

Data were obtained on 851 pupils enrolled in the five indexed schools. Anthropometric measures included weight for age, height for age, and relative weight for height, and the values were derived from the raw data. Percentage of attendance rates derived from daily school attendance and raw scores on the Kenya Certificate of Primary Education were the measures of educational participation and achievement. Statistical analysis included descriptive statistics, analyses of variance, correlation, and linear regression analyses.

RESULTS

Twenty-nine percent of the children fell below the 90% cutoff value for acceptable relative weight for height. The percentages of the population falling below -2 standard deviations on indices for height for age and weight for age were 16.64 and 3.78, respectively. Univariate analyses showed that anthropometric assessment varied by school and sex. School attendance rates varied by school and grade. Achievement scores on the Kenya Certificate of Primary Education varied by school and the interaction of sex by school. Regression analysis showed attendance rate to be the strongest predictor of achievement, followed by relative weight for height.

CONCLUSION

Prevalence of nutritional stress is a significant educational problem in this population. The association between attendance rate and nutrition status is a function of socioeconomic status. The predictive effect of nutrition status on educational achievement is more evident for girls with poor socioeconomic status.

Early childhood stunting and later behaviour and school achievement

BACKGROUND

Stunting in early childhood is common in developing countries and is associated with poorer cognition and school achievement in later childhood. The effect of stunting on children's behaviours is not as well established and is examined here.

METHOD

Children who were stunted at age 9 to 24 months and had taken part in a 2-year intervention programme of psychosocial stimulation with or without nutritional supplementation were reexamined at age 11-12 years and compared with non-stunted children from the same neighbourhoods. Their school and home behaviours were assessed using the Rutter Teacher and Parent Scales and school achievement was measured using the Wide Range Achievement Test (WRAT) and the Suffolk Reading Scales.

RESULTS

No significant intervention effects were found among the stunted groups. Thus data from the four intervention groups were aggregated for subsequent analyses, comparing all 116 stunted children with 80 non-stunted children. Controlling for social background variables, the stunted group had more conduct difficulties (p < .05) as rated by their parents. They also had significantly lower scores in arithmetic, spelling, word reading and reading comprehension than the non-stunted children (all p < .001). Conduct difficulties and hyperactivity were related to poorer school achievement. Controlling for the children's IQ, the stunted children's arithmetic scores remained significantly lower than those of the non-stunted children, but reading and spelling scores were not different.

CONCLUSIONS

Previously stunted children had more conduct difficulties at home, regardless of their social background, than non-stunted children. Their educational attainment was also poorer than non-stunted children and these results are suggestive of a specific arithmetic difficulty. Children with behaviour problems performed less well at school.

Effects of iron supplementation and anthelmintic treatment on motor and language development of preschool children in Zanzibar: double blind, placebo controlled study

OBJECTIVE

To measure the effects of iron supplementation and anthelmintic treatment on iron status, anaemia, growth, morbidity, and development of children aged 6-59 months.

DESIGN

Double blind, placebo controlled randomised factorial trial of iron supplementation and anthelmintic treatment.

SETTING

Community in Pemba Island, Zanzibar.

PARTICIPANTS

614 preschool children aged 6-59 months.

MAIN OUTCOME MEASURES

Development of language and motor skills assessed by parental interview before and after treatment in age appropriate subgroups.

RESULTS

Before intervention, anaemia was prevalent and severe, and geohelminth infections were prevalent and light-Plasmodium falciparum infection was nearly universal. Iron supplementation significantly improved iron status, but not haemoglobin status. Iron supplementation improved language development by 0.8 (95% confidence interval 0.2 to 1.4) points on the 20 point scale. Iron supplementation also improved motor development, but this effect was modified by baseline haemoglobin concentrations (P=0.015 for interaction term) and was apparent only in children with baseline haemoglobin concentrations <90 g/l. In children with a baseline haemoglobin concentration of 68 g/l (one standard deviation below the mean value), iron treatment increased scores by 1.1 (0.1 to 2.1) points on the 18 point motor scale. Mebendazole significantly reduced the number and severity of infections caused by Ascaris lumbricoides and Trichuris trichiura, but not by hookworms. Mebendazole increased development scores by 0.4 (-0.3 to 1.1) points on the motor scale and 0.3 (-0.3 to 0.9) points on the language scale.

CONCLUSIONS

Iron supplementation improved motor and language development of preschool children in rural Africa. The effects of iron on motor development were limited to children with more severe anaemia (baseline haemoglobin concentration <90 g/l). Mebendazole had a positive effect on motor and language development, but this was not statistically significant.

Intestinal parasitic infections

Our understanding of the biology of several intestinal parasites has progressed considerably in the past year, especially in the area of molecular biology. Information from molecular and genetic analyses has been used increasingly to improve understanding of pathogenesis, to apply improved diagnostic methods, and to seek new vaccination strategies. There were fewer relevant clinical studies than in previous years, but some are notable. Control of helminth infections by mass chemotherapy in school age children appears an achievable goal in many communities. Vaccine trials against some protozoan infections continue to show promise in animal models.