Effects of antiparasitic treatment on dynamically and statically tested cognitive skills over time

Impact of helminth-microbiome interactions on childhood health and development-A clinical perspective

Humans have co-existed with parasites for virtually the entirety of our existence as a species. Today, nearly one third of the human population is infected with at least one helminthic species, most of which reside in the intestinal tract, where they have co-evolved alongside the human gut microbiota (GM). Appreciation for the interconnected relationship between helminths and GM has increased in recent years. Here, we review the evidence of how helminths and GM can influence various aspects of childhood development and the onset of paediatric diseases. We discuss the emerging evidence of how many of the changes that parasitic worms inflict on their host is enacted through gut microbes. In this light, we argue that helminth-induced microbiota modifications are of great importance in both facing the global challenge of overcoming parasitic infections, and in replicating helminthic protective effects against inflammatory diseases. We propose that deepening our knowledge of helminth-microbiota interactions will uncover novel, safer and more effective therapeutic strategies in combatting an array of childhood disorders.

Soil zinc deficiency and child stunting: Evidence from Nepal

We examine the negative child health impacts of soil zinc (Zn) deficiency in Nepal. Soil Zn deficiency limits both crop yields and the Zn concentration in food crops, leading many to speculate that it underlies human Zn deficiency and child stunting, globally and particularly in South Asia. We find strong evidence that soil Zn deficiency does have a causal impact on child stunting in Nepal's Tarai region, the breadbasket of the country. Using causal bounds, we find that a 1 part per million increase in plant-available soil Zn - achievable with application of Zn-enriched fertilizer - decreases child stunting by between 1 and 7.5 percentage points. Multiple statistical sensitivity tests indicate that this relationship is unlikely to be manufactured by omitted, relevant variables.

Spreading the Wealth: Developing Assessments of Cognitive Abilities in Non-WEIRD Countries

In this brief essay I reminisce on the ideas I encountered in Lev Vygotsky's lectures on pedology as an undergraduate student at Moscow State University in the USSR. Some of these ideas have been reliably stored in my professional memory and have influenced how my colleagues and I have approached the assessment of IQ (or general cognitive abilities) in countries other than the ones in which they were developed. Whereas the essay is autobiographical in nature, it attempts to make a generalizable point that spreading the wealth of existing knowledge, principles, and practice is as central to the progress of science as generating new knowledge.

Association of iron supplementation and deworming with early childhood development: analysis of Demographic and Health Surveys in ten low- and middle-income countries

PURPOSE

We assessed the associations of iron supplementation and deworming separately or combined with improved early childhood development (ECD) status.

METHODS

Cross-sectional data were analyzed for 29,729 children aged 36-59 months surveyed using the Demographic and Health Surveys in ten low- and middle-income countries, where iron supplementation and deworming are recommended by the World Health Organization. In each country, we estimated linear regression models for the effects of iron supplementation and deworming individually or combined on the Early Childhood Development Index (ECDI) z score, and whether this association differed between various ECD domains and the sex and residence of the child. Estimates were pooled using random-effects meta-analyses.

RESULTS

Compared with receiving neither of the two interventions, iron supplementation plus deworming was associated with an increased ECDI z score (β = 0.13, 95% confidence interval (CI) 0.03-0.22, p = 0.009), particularly in rural residences. However, iron supplementation and deworming, individually, were not associated with the ECDI z score. Iron supplementation plus deworming was associated with higher odds of on-track development in literacy-numeracy (OR = 1.57, 95% CI 1.24-2.01, p < 0.001) and learning domains (OR = 1.27, 95% CI 1.09-1.48, p = 0.003), but not with development in the social-emotional and physical domains.

CONCLUSION

Iron supplementation plus deworming, particularly for populations who are more susceptible to iron deficiency and intestinal worm infections, could be an important intervention for improving ECD. These findings may inform the argument for the necessity of implementing iron supplementation and deworming for preschool-age children.

Cognitive and Microbiome Impacts of Experimental Ancylostoma ceylanicum Hookworm Infections in Hamsters

Hookworms are one of the most prevalent and important parasites, infecting ~500 million people worldwide. Hookworm disease is among the leading causes of iron-deficiency anemia in the developing world and is associated with significant growth stunting and malnutrition. In humans, hookworms appear to impair memory and other forms of cognition, although definitive data are hard to come by. Here we study the impact of a human hookworm parasite, Ancylostoma ceylanicum, on cognition in hamsters in a controlled laboratory setting. We developed tests that measure long-term memory in hamsters. We find that hookworm-infected hamsters were fully capable of detecting a novel object. However, hookworm-infected hamsters were impaired in detecting a displaced object. Defects could be discerned at even at low levels of infection, whereas at higher levels of infection, hamsters were statistically unable to distinguish between displaced and non-displaced objects. These spatial memory deficiencies could not be attributed to defects in infected hamster mobility or to lack of interest. We also found that hookworm infection resulted in reproducible reductions in diversity and changes in specific taxanomic groups in the hamster gut microbiome. These data demonstrate that human hookworm infection in a laboratory mammal results in a specific, rapid, acute, and measurable deficit in spatial memory, and we speculate that gut alterations could play some role in these cognitive deficits. Our findings highlight the importance of hookworm elimination and suggest that finer tuned spatial memory studies be carried out in humans.

Determinants of Spatial Heterogeneity of Functional Illiteracy among School-Aged Children in the Philippines: An Ecological Study

Functional literacy is one of the targets of the Sustainable Development Goals (SDGs) of the United Nations. Functional literacy indicators are likely to vary between locations given the geographical variability of its major determinants. This property poses a challenge to decisions around efficient allocation of population services and resources to mitigate the impact of functional literacy in populations most in need. Using functional literacy indicators of 11,313 school-aged children collected in 2008 during the nationwide survey, the current study examined the association between functional literacy and geographical disparities in socioeconomic status (SES), water supply, sanitation and hygiene, household education stimuli, and environmental variables in all three regions of the Philippines (Luzon, the Visayas, and Mindanao). Three nested fixed-effects multinomial regression models were built to determine associations between functional literacy and a wide array of variables. Our results showed the general prevalence rate of functional illiteracy as being 4.7%, with the highest prevalence rate in the Visayas, followed by Mindanao and Luzon (7.5%, 6.9%, and 3.0%, respectively. Our results indicated that in Luzon prevalence of functional illiteracy was explained by variation in household education stimuli scores, sources of drinking water, and type of toilet facility. In Mindanao and the Visayas prevalence of functional illiteracy was primarily explained by geographical variation in SES, and natural environmental conditions. Our study highlights region-specific determinants of functional literacy and the need for geographically targeted, integrated interventions.

Deworming in non-pregnant adolescent girls and adult women: a systematic review and meta-analysis

BACKGROUND

The impact of deworming on parasite load, nutritional status and other health outcomes of non-pregnant adolescent girls and adult women is uncertain.

METHODS

MEDLINE, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials, the WHO International Clinical Trials Registry Platform, the Cochrane Database of Systematic Reviews and Food and Technology Abstracts databases were searched until 24 September 2018. Studies were included if they were randomised controlled trials (RCTs), controlled before and after studies or interrupted time studies comparing deworming with no intervention or placebo in non-pregnant adolescent girls and women 10 to 49 years old. Outcomes of interest included parasite load, reinfection, anaemia, severe anaemia, iron deficiency, diarrhoea or all-cause morbidity. Risk of bias was assessed using the Cochrane risk of bias tool.

RESULTS

We included four RCTs of mass deworming involving 1086 participants, in the analyses. Mass deworming probably reduces the prevalence of roundworm infection (RR 0.29; 95% CI 0.14 to 0.62; 2 trials; 1498 participants, moderate certainty evidence), prevalence of hookworm infection (RR 0.32; 95% CI 0.18 to 0.59; 2 trials; 1498 participants, moderate certainty evidence), prevalence of whipworm infection (RR 0.77; 95% CI 0.65 to 0.91; 2 trials; 1498 participants, moderate certainty evidence) compared to the control group. Deworming may make little or no difference in prevalence of anaemia (RR 0.82; 95% CI 0.60 to 1.11, 3 studies, 683 participants, low certainty evidence) and prevalence of iron-deficiency (RR 0.89; 95% CI 0.64 to 1.23, 1 study, 186 participants, low certainty evidence) compared to control. We are uncertain whether deworming reduces the prevalence of severe anaemia compared to control as the certainty of evidence was very low. None of the included studies assessed screen and treat deworming or reported reinfection, diarrhoea or adverse events.

CONCLUSIONS

Mass deworming probably reduces the prevalence of soil-transmitted helminth infections but may have little or no effect on anaemia and iron-deficiency in adolescent girls and non-pregnant women in comparison to no intervention or placebo. We are uncertain about the effect on severe anaemia. These results are limited by sparse data and the moderate to very low quality of evidence available.

SYSTEMATIC REVIEW REGISTRATION

The protocol was registered in PROSPERO (registration number: CRD42016039557 ).  Primary source of funding: Evidence and Programme Guidance unit, Department of Nutrition for Health and Development, World Health Organization (WHO).

Cognitive deficits and educational loss in children with schistosome infection-A systematic review and meta-analysis

Background

By means of meta-analysis of information from all relevant epidemiologic studies, we examined the hypothesis that Schistosoma infection in school-aged children (SAC) is associated with educational loss and cognitive deficits.

Methodology/Principal findings

This review was prospectively registered in the PROSPERO database (CRD42016040052). Medline, Biosis, and Web of Science were searched for studies published before August 2016 that evaluated associations between Schistosoma infection and cognitive or educational outcomes. Cognitive function was defined in four domains—learning, memory, reaction time, and innate intelligence. Educational outcome measures were defined as attendance and scholastic achievement. Risk of bias (ROB) was evaluated using the Newcastle-Ottawa quality assessment scale. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated to compare cognitive and educational measures for Schistosoma infected /not dewormed vs. uninfected/dewormed children. Sensitivity analyses by study design, ROB, and sequential exclusion of individual studies were implemented. Thirty studies from 14 countries, including 38,992 SAC between 5–19 years old, were identified. Compared to uninfected children and children dewormed with praziquantel, the presence of Schistosoma infection and/or non-dewormed status was associated with deficits in school attendance (SMD = -0.36, 95%CI: -0.60, -0.12), scholastic achievement (SMD = -0.58, 95%CI: -0.96, -0.20), learning (SMD = -0.39, 95%CI: -0.70, -0.09) and memory (SMD = -0.28, 95%CI: -0.52, -0.04) tests. By contrast, Schistosoma-infected/non-dewormed and uninfected/dewormed children were similar with respect to performance in tests of reaction time (SMD = -0.06, 95%CI: -0.42, 0.30) and intelligence (SMD = -0.25, 95%CI: -0.57, 0.06). Schistosoma infection-associated deficits in educational measures were robust among observational studies, but not among interventional studies. The significance of infection-associated deficits in scholastic achievement was sensitive to ROB. Schistosoma infection-related deficits in learning and memory tests were invariant by ROB and study design.

Conclusion/Significance

Schistosoma infection/non-treatment was significantly associated with educational, learning, and memory deficits in SAC. Early treatment of children in Schistosoma-endemic regions could potentially mitigate these deficits.

Trial registration

ClinicalTrials.gov CRD42016040052

Empirical evidence for cognitive or educational benefits of anti-Schistosoma treatment is currently uncertain, despite the recommended practice of wide-scale deworming with praziquantel. We addressed this knowledge gap by synthesizing information from 30 relevant epidemiologic studies reporting on 38,992 children between 5–19 years old from 14 countries. In those studies, Schistosoma infection or non-dewormed status was associated with educational loss and cognitive deficits. Specifically, there were small to moderate deficits in both school attendance and scholastic achievement. Similarly, Schistosoma infection or non-dewormed status was associated with deficits in learning and memory domains of psychometrically tested cognitive function. However, there was no evidence of Schistosoma infection- or non-deworming-associated deficits on tests of innate intelligence or reaction-time. Overall, compared to Schistosoma-uninfected or to dewormed children, the presence of Schistosoma infection or non-dewormed status was associated with educational, learning, and memory deficits in school-aged children. The combined evidence suggests that early treatment of children in Schistosoma-endemic regions could mitigate these deficits.

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.

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.

The cross-cutting contribution of the end of neglected tropical diseases to the sustainable development goals

The Sustainable Development Goals (SDGs) call for an integrated response, the kind that has defined Neglected Tropical Diseases (NTDs) efforts in the past decade.NTD interventions have the greatest relevance for SDG3, the health goal, where the focus on equity, and its commitment to reaching people in need of health services, wherever they may live and whatever their circumstances, is fundamentally aligned with the target of Universal Health Coverage. NTD interventions, however, also affect and are affected by many of the other development areas covered under the 2030 Agenda. Strategies such as mass drug administration or the programmatic integration of NTD and WASH activities (SDG6) are driven by effective global partnerships (SDG17). Intervention against the NTDs can also have an impact on poverty (SDG1) and hunger (SDG2), can improve education (SDG4), work and economic growth (SDG8), thereby reducing inequalities (SDG10). The community-led distribution of donated medicines to more than 1 billion people reinforces women's empowerment (SDG5), logistics infrastructure (SDG9) and non-discrimination against disability (SDG16). Interventions to curb mosquito-borne NTDs contribute to the goals of urban sustainability (SDG11) and resilience to climate change (SDG13), while the safe use of insecticides supports the goal of sustainable ecosystems (SDG15). Although indirectly, interventions to control water- and animal-related NTDs can facilitate the goals of small-scale fishing (SDG14) and sustainable hydroelectricity and biofuels (SDG7).NTDs proliferate in less developed areas in countries across the income spectrum, areas where large numbers of people have little or no access to adequate health care, clean water, sanitation, housing, education, transport and information. This scoping review assesses how in this context, ending the epidemic of the NTDs can impact and improve our prospects of attaining the SDGs.

'WE CAN'T GET WORMS FROM COW DUNG': REPORTED KNOWLEDGE OF PARASITISM AMONG PASTORALIST YOUTH ATTENDING SECONDARY SCHOOL IN THE NGORONGORO CONSERVATION AREA, TANZANIA

Records at the Endulen Hospital in the Ngorongoro Conservation Area (NCA), Tanzania, reveal that soil-transmitted helminth infections and protozoa are consistently in the top ten diagnoses for Maasai pastoralists, indicating a significant public health concern. Nevertheless, Maasai pastoralist adaptations to life in close proximity to livestock and to unreliable access to water raise important questions about experiences of, and resiliency to, parasitic infections. Though these infections are particularly prevalent among youth in low- and middle-income countries (LMIC), a focus on resiliency highlights local capacity to recover from and prevent illness. For instance, how is human parasitism perceived and experienced among communities displaying behaviours that studies have associated with transmission of diarrhoeal diseases, such as open defecation? Among these communities, how is parasitism seen to impact the health and development of children? And, what resources are available to endure or mitigate this heavy disease burden among affected communities? This study draws on formative research carried out in May 2014 in anticipation of an innovative school-based and youth-driven water, sanitation and hygiene education intervention rolled out in two boarding schools in the NCA in subsequent months. The initiative is grounded in a One Health approach to health promotion, drawing on partnerships in medicine, public health and veterinary medicine to appreciate the unique interactions between humans, animals and the environment that shape well-being among pastoralist communities. Qualitative data generated through group discussions with secondary school youth (n=60), Maasai teachers (n=6) and a women's group (n=8) in the NCA convey existing knowledge of the prevalence, prevention and treatment of human parasitism. An underlying principle of the larger initiative is to engage youth as creative agents of change in developing and sustaining locally relevant health promotion strategies. Findings highlight practical knowledge around certain 'neglected tropical diseases', namely helminths, among pastoralist communities in the NCA, in turn feeding into the development of the science fair and related interventions.

Enhancing the child survival agenda to promote, protect, and support early child development

High rates of child mortality and lost developmental potential in children under 5 years of age remain important challenges and drivers of inequity in the developing world. Substantive progress has been made toward Millennium Development Goal (MDG) 4 to improve child survival, but as we move into the post-2015 sustainable development agenda, much more work is needed to ensure that all children can realize their full and holistic physical, cognitive, psychological, and socio-emotional development potential. This article presents child survival and development as a continuous and multifaceted process and suggests that a life-course perspective of child development should be at the core of future policy making, programming, and research. We suggest that increased attention to child development, beyond child survival, is key to operationalize the sustainable development goals (SDGs), address inequities, build on the demographic dividend, and maximize gains in human potential. An important step toward implementation will be to increase integration of existing interventions for child survival and child development. Integrated interventions have numerous potential benefits, including optimization of resource use, potential additive impacts across multiple domains of health and development, and opportunity to realize a more holistic approach to client-centered care. However, a notable challenge to integration is the continued division between the health sector and other sectors that support child development. Despite these barriers, empirical evidence is available to suggest that successful multisectoral coordination is feasible and leads to improved short- and long-term outcomes in human, social, and economic development.

Effects of geohelminth infections on neurological development

Published reviews vary on the question of whether geohelminth infections affect cognitive development: some claim that the scarcity of evidence means that it is unlikely that they do; others present modest evidence for an effect; and others raise the possibility that the damage is considerable but largely unresearched. This chapter reviews the characteristics of the geohelminths themselves and the pathways by which they could affect the development of children in endemic areas. It describes the progress made in the last decade in conceptualizing children's brains as complex adaptive systems, with the suggestion that infections at different stages in brain development might have different neurobehavioral consequences. An examination of research reports and review articles highlights the difficulties inherent in assessing the effects of geohelminth infections: other serious obstacles to healthy development in the same population may mask the effects of the geohelminths, and consequently the intensity and pathogenicity of the infection is probably an important issue. Selecting cognitive measures suitable for assessing development in very young children is no simple matter, and careful statistical analysis is required to tease out the primary and secondary factors at work. The insights gained from a broad range of relevant research reports have placed us in a better position to conduct more telling research into the effects of these widespread, but neglected, tropical diseases.

Development of cognitive abilities of children infected with helminths through health education

INTRODUCTION

The aim of this study was to evaluate the effect of health education in learning and cognitive development of children infected, previously treated in an endemic area for helminthiasis.

METHODS

It is a longitudinal, experimental, with random allocation of participants. The study included 87 children of both sexes enrolled in the school hall of Maranhão, State of Minas Gerais, Brazil, and divided into two groups: intervention and control. Initially the children were submitted to the parasitological fecal examination for infection diagnosis and, when positive, they were treated. For the data collection, a structured questionnaire and the psychological tests Raven, Wisc-III and DAP III were applied, before and after the educational intervention. For the group comparison, the Mann Whitney test was used, and established significance level of 5%.

RESULTS

It was found that previously infected children who received the educational intervention, children showed higher performance than the control group in strutured questionnaire (p<0.05).

CONCLUSIONS

It is acceptable to suppose the positive influence and the importance in the use of educational interventions in the cognitive recovery and learning of children previously treated with anthelmintics.

Improving educational achievement and anaemia of school children: design of a cluster randomised trial of school-based malaria prevention and enhanced literacy instruction in Kenya

BACKGROUND

Improving the health of school-aged children can yield substantial benefits for cognitive development and educational achievement. However, there is limited experimental evidence on the benefits of school-based malaria prevention or how health interventions interact with other efforts to improve education quality. This study aims to evaluate the impact of school-based malaria prevention and enhanced literacy instruction on the health and educational achievement of school children in Kenya.

DESIGN

A factorial, cluster randomised trial is being implemented in 101 government primary schools on the coast of Kenya. The interventions are (i) intermittent screening and treatment of malaria in schools by public health workers and (ii) training workshops and support for teachers to promote explicit and systematic literacy instruction. Schools are randomised to one of four groups: receiving either (i) the malaria intervention alone; (ii) the literacy intervention alone; (iii) both interventions combined; or (iv) control group where neither intervention is implemented. Children from classes 1 and 5 are randomly selected and followed up for 24 months. The primary outcomes are educational achievement and anaemia, the hypothesised mediating variables through which education is affected. Secondary outcomes include malaria parasitaemia, school attendance and school performance. A nested process evaluation, using semi-structured interviews, focus group discussion and a stakeholder analysis will investigate the community acceptability, feasibility and cost-effectiveness of the interventions.

DISCUSSION

Across Africa, governments are committed to improve health and education of school-aged children, but seek clear policy and technical guidance as to the optimal approach to address malaria and improved literacy. This evaluation will be one of the first to simultaneously evaluate the impact of health and education interventions in the improvement of educational achievement. Reflection is made on the practical issues encountered in conducting research in schools in Africa.

TRIAL REGISTRATION

National Institutes of Health NCT00878007.

Self-rated quality of life and school performance in relation to helminth infections: case study from Yunnan, People's Republic of China

Background

Expert opinion-derived disability weights are widely employed for estimating the global burden of diseases and injuries. For chronic diseases such as soil-transmitted helminthiasis and schistosomiasis, it has been suggested that a patient-based quality of life (QoL) approach should be considered for a more accurate appraisal of disability weights.

Methods and Results

We carried out a cross-sectional survey and assessed the prevalence and intensity of soil-transmitted helminth infections as well as self-rated QoL indicators among 252 students attending grades 5-8 in two schools (Bulangshan and Pu'er) in Yunnan province, People's Republic of China. Each student provided a single stool sample, which was subjected to duplicate Kato-Katz thick smear readings and a single FLOTAC examination for parasitological diagnosis. Prevalence rates for hookworm, Trichuris trichiura and Ascaris lumbricoides were high in Bulangshan (75.9%, 70.0% and 68.2%), while the respective prevalence rates in Pu'er were 66.9%, 56.5% and 9.2%. Students were interviewed with two standardised questionnaires, the EuroQoL-5 Dimensions (EQ-5D) and ShortForm-12 (SF-12) Health Survey. Impairment in any of the five dimensions of the EQ-5D was reported by 87% of the students. However, no clear differences could be observed between individuals with and those without helminth infections, and there were discrepancies between the two schools. A multivariate logistic regression model revealed no differences between students with varying infection status in the domains of the SF-12 (odds ratio close to 1.0). Somewhat more pronounced, yet not statistically significant differences were observed when end-of-school-term marks were compared with students' helminth infection status: infected individuals had lower marks in Chinese, English and mathematics, but not in sports, compared to their helminth-free counterparts.

Conclusions

Our results point to unresolved issues and challenges regarding the cultural appropriateness of the widely used standard QoL questionnaires. Hence, new research is needed to further develop these instruments and to validate them in connection with chronic parasitic diseases.

Dynamic assessment and response to intervention: two sides of one coin

This article compares and contrasts the main features of dynamic testing and assessment (DT/A) and response to intervention (RTI). The comparison is carried out along the following lines: (a) historical and empirical roots of both concepts, (b) premises underlying DT/A and RTI, (c) terms used in these concepts, (d) use of these concepts, (e) evidence in support of DT/A and RTI, and (f) expectations associated with each of the concepts. The main outcome of this comparison is a conclusion that both approaches belong to one family of methodologies in psychology and education whose key feature is in blending assessment and intervention in one holistic activity. Because DT/A has been around much longer than RTI, it makes sense for the proponents of RTI to consider both the accomplishments and frustrations that have accumulated in the field of DT/A.