Commentary: Replication of influential trial helps international policy Evidence for spending millions on deworming schoolchildren is inadequate, report says Effect of Deworming on Indices of Health, Cognition, and Education Among Schoolchildren in Rural China: A Cluster-Randomized Controlled Trial. Effects of Deworming on Malnourished Preschool Children in India: An Open-Labelled, Cluster-Randomized Trial The impact of mass deworming programmes on schooling and economic development: an appraisal of long-term studies The Effect of Deworming on Growth in One-Year-Old Children Living in a Soil-Transmitted Helminth-Endemic Area of Peru: A Randomized Controlled Trial Cluster-randomised trial of the impact of school-based deworming and iron supplementation on the cognitive abilities of schoolchildren in Sri Lanka's plantation sector. Effects of a Post-Deworming Health Hygiene Education Intervention on Absenteeism in School-Age Children of the Peruvian Amazon Cluster-randomised controlled trials of individual and combined water, sanitation, hygiene and nutritional interventions in rural Bangladesh and Kenya: the WASH Benefits study design and rationale Effect of deworming on nutritional status of ascaris infested slum children of Dhaka, Bangladesh. School-based deworming program yields small improvement in growth of Zanzibari school children after one year. Effects of the Zanzibar school-based deworming program on iron status of children. Effect of Deworming on Physical Fitness of School-Aged Children in Yunnan, China: A Double-Blind, Randomized, Placebo-Controlled Trial (S)WASH-D for Worms: A pilot study investigating the differential impact of school- versus community-based integrated control programs for soil-transmitted helminths A Double-Blind Randomized Controlled Trial of Maternal Postpartum Deworming to Improve Infant Weight Gain in the Peruvian Amazon Effectiveness of a rural sanitation programme on diarrhoea, soil-transmitted helminth infection, and child malnutrition in Odisha, India: a cluster-randomised trial. Impact of Health Education on Soil-Transmitted Helminth Infections in Schoolchildren of the Peruvian Amazon: A Cluster-Randomized Controlled Trial
The World Bank , the Gates Foundation and the World Health Organization promote national child deworming programmes in developing countries.1 They assert these programmes will improve nutritional status , health and school performance , and hence contribute to economic growth . Indeed , the World Health Organization states that deworming contributed to Japan ’s economic boom in the 1950s,2 and Nobel Laureates meeting in Copenhagen ranked deworming as the fourth most important intervention to solve the health problems of the whole world.3 Surprisingly , the evidence base for these cl aims from controlled studies is limited . Critically , according to the Cochrane review which two of us author , there is quite good evidence of no effect for the main biomedical outcomes in deworming , making the broader societal benefits on economic development barely credible ( Figure 1).4 Nevertheless , the advocates increasingly rely on a single large quasi-r and omized trial carried out in Kenya , published in 2004 in Econometrica,5 which reports school attendance . Figure 1 . Conceptual framework used to underpin the effects of deworming programmes on economic growth  in developing countries . Contemporary evidence questions this model , as there is now quite good contemporary evidence , summarized in the Cochrane review , that ... This study has been highly influential . The International Initiative for Impact Evaluation commissioned the London School of Hygiene and Tropical Medicine ( LSHTM ) to replicate the analysis , as the original analysis is ‘ based on econometric approaches and used a language and format that would be unfamiliar to many health care research ers’.6 The replication aim ed to provide detail of the methods and reporting in line with the CONSORT statement . The team are internationally recognized , independent and meticulous in their approach . They agreed a protocol , carefully checked and corrected the raw data , and then re-ran their prespecified analysis .6 Their first paper is a pure replication,7 exactly repeating the authors ’ original analysis . This paper clarifies some method ological details not provided in the original paper , but it also uncovers a series of important coding and analysis errors . Some of the corrected results are consistent with the original findings , but others are quite different . Most notably , the much quoted ‘ positive externalities’—where the benefits of treating children in one school ‘ spill over ’ to benefit children in adjacent schools — vanish in their corrected analysis . Their second paper uses approaches more familiar to epidemiologists , and allows a more thorough exploration of the data .8 There are substantial amounts of missing information , and some unexpected patterns that are difficult to explain . For example , there is a correlation between the number of observations in each school and the reported attendance , with more observations associated with lower attendance reported — except in some of the intervention groups , where more frequent observation is associated with better attendance . This raises the possibility that the process of observation influenced outcome reporting and this was different in control and intervention groups . The second paper confirms an association with higher attendance in the deworming schools when stratified by year , but found the combined estimate across years was much larger , and the authors caution the validity of the combined year estimate : this may be due to the stepped-wedge design where the combined year estimate includes a before and after comparison ; or it may be due to the problems with secular and group effects of the number of observations of school attendance varying . To further complicate matters , there was also a concurrent ‘ School Assistance Program ’ ( SAP ) evaluating five other interventions in 27/75 of the study schools , which was not part of the r and omized intervention . Attendance patterns differed on the basis of involvement in the SAP , which the authors suggest could well lead to bias.8 One of the critical points the LSHTM papers make is that the administration of the deworming drugs was part of a ‘ complex health education and drug treatment intervention’.8 The intervention schools also received regular public health lectures , wall charts and teacher training on worm prevention . Interestingly , the pure replication shows very similar impacts of the intervention on children in the intervention schools irrespective of whether they took the deworming medicine or not.7 For Miguel and colleagues , they term this as ‘ indirect within-school effects ’ of deworming , but equally the effects could be due to the non-specific effects of the health promotion interventions in the intervention schools . So where does this take us ? There is a small effect on school attendance for sure , but this should not be over-interpreted , as the LSHTM authors say , given the concerns raised regarding the risk of bias , and the independent effects on school attendance of the programme of health promotion . In addition , the study shows that allocation to the deworming group does not influence student progress , as the re- analysis shows clearly no evidence of a difference in examination performance between deworming and control groups.7,8 In the context of the global evidence base , there is only one other study that has examined school attendance with no obvious effect shown.4 Given all these uncertainties , we simply do n’t know if there is truly an effect on school attendance from the data , in taking all these factors into account formally in a GRADE analysis .4 But what weakens the case of deworming still further is that there is now quite good evidence of no effect for most of the main outcomes ( Figure 1 ) , including nutritional status , haemoglobin , cognition and school performance . This is important because without these effects it seems implausible that deworming itself would have an independent effect on school attendance or economic development . Obviously children infected with worms should be treated . Trials from over 20 years ago in an area of Kenya where all the children were heavily infected showed benefit . Another trial in India showed benefit , but subsequent trials in the same area failed to show an effect.4,9 So deworming may have helped in these exceptional , heavily infected , untreated population s from another decade , but this is scarcely a solid base for contemporary policy : public health nutrition has changed , worm burden has declined and this probably accounts for the lack of effect on biomedical outcomes in contemporary studies .10 We have been perplexed by the un question ing belief behind deworming in the advocates , and have found it is deep rooted in American history . The Rockefeller Sanitary Commission in 1909 sought to eradicate hookworm in the Southern USA population , where it was seen as a cause of ‘ some of the proverbial laziness of the poorer classes ’ and to improve worker productivity ; these were extended with the Rockefeller International Health Commission established in 1913.11 The beliefs and assumptions appear to continue , with ‘ Deworm the World ’ aim ing to deworm 220 million children in India during 2015.12 What have we learned from this ? Certainly that replication is a valuable process , not least for errors that have the potential to mislead , but also to provide a much better interpretation of the potential biases in studies . In terms of policies in deworming , it suggests donors and Nobel Prize winners need to be aware of their prior assumptions , and base decisions on the all the evidence from reliable studies within a systematic review , not just select a single study . They need to look at all relevant outcomes , not just one . They need to consider bias and confounding . Our view is that current promotion of community deworming is certainly a panacea : a single solution to multiple problems in low- and middle-income countries , and that the belief that deworming will impact substantially on economic development seems delusional when you look at the results of reliable controlled trials . This is a view , based on over 15 years of engagement with critically appraising the literature in this field.13 We recommend anyone responsible for public or philanthropic money going to large scale deworming to read these replication studies , the original publication , the authors ’ responses to the replication and the 2015 version of the Cochrane review that includes corrections from these replications plus data from five further studies , including the recently published DEVTA study of 2 million children.4,14 Then make up your own mind . Conflict of interest : PG and DTR are authors of a Cochrane review of community deworming programmes . PG is funded by the Department for International Development to provide reliable independent systematic review s for the benefit of developing countries ; PG receives salary support from Countdown , a DFID-supported research grant in programmatic implementation of neglected tropical disease programmes New analysis of a l and mark paper on the health and economic benefits of eliminating worm infections in children has found little evidence that it does any good . Deworming programmes have been heavily promoted by the World Bank , the World Health Organization , and international charities as a key to improving health , school performance , and , by inference , economic development in poor and middle income countries . India has recently launched the world ’s largest deworming programme , with the aim of treating 240 million children once or twice a year with albendazole , a drug that can eliminate worm infections.1 The policy relies on a limited evidence base , with a single r and omised trial carried out in 75 Kenyan schools regularly cited by its proponents . In this 2004 study Edward Miguel of the University of California at Berkeley and Michael Kramer of Harvard University found that the treated children had a lower prevalence of worm infestation , improved nutritional status , and higher school attendance.2 Importantly , they also found that these benefits extended to untreated children in the treated schools and to Abstract Soil-transmitted helminths ( STHs ) infect over one billion people worldwide . There is concern that chronic infection with STHs among school-aged children may detrimentally affect their development , including their health , cognition , and education . However , two recent Cochrane review s examining the impact of deworming drugs for STH on nutrition , hemoglobin , and school performance found that r and omized controlled trials ( RCTs ) in the literature provide an insufficient evidence base to draw reliable conclusions . This study uses a cluster- RCT to add to existing evidence by assessing the impact of a deworming intervention on nutrition , cognition , and school performance among schoolchildren in rural China . The intervention , implemented by local health practitioners in a setting with a baseline infection prevalence of 41.9 % ( 95 % confidence interval [ CI ] = 39.8 % , 43.9 % ) and infection intensity of 599.5 eggs per gram of feces among positive-tested schoolchildren ( 95 % CI = 473.2 , 725.8 ) , consisted of distributing a 400-mg dose of albendazole accompanied with educational training about STH infection , treatment , and prevention . The intervention was conducted twice over the course of the study -at baseline in May 2013 and later in November 2013 . We found that the deworming intervention reduced both infection prevalence and infection intensity , but these declines in infection were not accompanied by an impact on outcomes of nutrition , cognition , or school performance . Our interpretation is that the impact of deworming was attenuated by the light infection intensity in our sample population . Evidence from future RCTs is needed to assess the effect of deworming on key outcomes in areas with moderate and severe worm infections Background More than a third of the world 's children are infected with intestinal nematodes . Current control approaches emphasise treatment of school age children , and there is a lack of information on the effects of deworming preschool children . Methodology We studied the effects on the heights and weights of 3,935 children , initially 1 to 5 years of age , of five rounds of anthelmintic treatment ( 400 mg albendazole ) administered every 6 months over 2 years . The children lived in 50 areas , each defined by precise government boundaries as urban slums , in Lucknow , North India . All children were offered vitamin A every 6 months , and children in 25 r and omly assigned slum areas also received 6-monthly albendazole . Treatments were delivered by the State Integrated Child Development Scheme ( ICDS ) , and height and weight were monitored at baseline and every 6 months for 24 months ( trial registration number NCT00396500 ) . p Value calculations are based only on the 50 area-specific mean values , as r and omization was by area . Findings The ICDS infrastructure proved able to deliver the interventions . 95 % ( 3,712/3,912 ) of those alive at the end of the study had received all five interventions and had been measured during all four follow-up surveys , and 99 % ( 3,855/3,912 ) were measured at the last of these surveys . At this final follow up , the albendazole-treated arm exhibited a similar height gain but a 35 ( SE 5 ) % greater weight gain , equivalent to an extra 1 ( SE 0.15 ) kg over 2 years ( 99 % CI 0.6–1.4 kg , p = 10−11 ) . Conclusions In such urban slums in the 1990s , five 6-monthly rounds of single dose anthelmintic treatment of malnourished , poor children initially aged 1–5 years results in substantial weight gain . The ICDS system could provide a sustainable , inexpensive approach to the delivery of anthelmintics or micronutrient supplements to such population s. As , however , we do not know the control parasite burden , these results are difficult to generalize . Trial Registration Clinical Trials.gov Abstract Background : Documents from advocacy and fund-raising organizations for child mass deworming programmes in low- and middle-income countries cite unpublished economic studies cl aim ing long-term effects on health , schooling and economic development . Methods : To summarize and appraise these studies , we search ed for and included all long-term follow-up studies based on cluster-r and omized trials included in a 2015 Cochrane review on deworming . We used Cochrane methods to assess risk of bias , and appraised the credibility of the main findings . Where necessary we contacted study authors for clarifications . Results : We identified three studies ( Baird 2016 , Ozier 2016 and Croke 2014 ) evaluating effects more than 9 years after cluster-r and omized trials in Kenya and Ug and a. Baird and Croke evaluate short additional exposures to deworming programmes in setting s where all children were dewormed multiple times . Ozier evaluates potential spin-off effects to infants living in areas with school-based deworming . None of the studies used pre-planned protocol s nor blinded the analysis to treatment allocation . Baird 2016 has been presented online in six iterations . The work is at high risk of reporting bias and selective reporting , and there are substantive changes between versions . The main cited effects on secondary school attendance and job sector allocation are from post hoc subgroup analyses , which the study was not powered to assess . The study did not find any evidence of effect on nutritional status , cognitive tests or school grade s achieved , but these are not reported in the abstract s. Ozier 2016 has been presented online in four iterations , without substantive differences between versions . Higher cognitive test scores were associated with deworming , but the appropriate analysis was underpowered to reliably detect these effects . The size of the stated effect seems inconsistent with the short and indirect nature of the exposure to deworming , and a causal pathway for this effect is unclear . Croke 2014 uses a data set unrelated to the base trial , to report improvements in English and maths test scores . The analysis is at high risk of attrition bias , due to loss of clusters , and is substantially underpowered to assess these effects . Conclusions : In the context of reliable epidemiological methods , all three studies are at risk of substantial method ological bias . They therefore help in generating hypotheses , but should not be considered to provide reliable evidence of effects Background Appropriate health and nutrition interventions to prevent long-term adverse effects in children are necessary before two years of age . One such intervention may include population -based deworming , recommended as of 12 months of age by the World Health Organization in soil-transmitted helminth (STH)-endemic areas ; however , the benefit of deworming has been understudied in early preschool-age children . Methodology /Principal Findings A r and omized , double-blind , placebo-controlled trial was conducted to determine the effect of  deworming ( 500 mg single-dose crushed mebendazole tablet ) on growth in one-year-old children in Iquitos , Peru . Children were enrolled during their routine 12-month growth and development clinic visit and followed up at their 18 and 24-month visits . Children were r and omly allocated to : Group 1 : deworming at 12 months and placebo at 18 months ; Group 2 : placebo at 12 months and deworming at 18 months ; Group 3 : deworming at both 12 and 18 months ; or Group 4 : placebo at both 12 and 18 months ( i.e. control group ) . The primary outcome was weight gain at the 24-month visit . An intention-to-treat approach was used . A total of 1760 children were enrolled between September 2011 and June 2012 . Follow-up of 1563 children ( 88.8 % ) was completed by July 2013 . STH infection was of low prevalence and predominantly light intensity in the study population . All groups gained between 1.93 and 2.05 kg on average over 12 months ; the average difference in weight gain ( kg ) compared to placebo was : 0.05 ( 95 % CI : -0.05 , 0.17 ) in Group 1 ; -0.07 ( 95%CI : -0.17 , 0.04 ) in Group 2 ; and 0.04 ( 95%CI : -0.06 , 0.14 ) in Group 3 . There was no statistically significant difference in weight gain in any of the deworming intervention groups compared to the control group . Conclusions Overall , with one year of follow-up , no effect of deworming on growth could be detected in this population of preschool-age children . Low baseline STH prevalence and intensity and /or access to deworming drugs outside of the trial may have diluted the potential effect of the intervention . Additional research is required to overcome these challenges and to contribute to strengthening the evidence base on deworming . Trial Registration Clinical Trials.gov ( NCT01314937 OBJECTIVE To assess the impact of deworming and iron supplementation on the cognitive abilities and educational achievement of school-age children in Sri Lanka . METHODS Prospect i ve , placebo-controlled r and omised study . The treatment group received deworming and weekly iron supplementation for 6 months ; the control group received placebo for both the anthelmintic and iron . A mixed effects regression model was used to answer the main research question . To increase the precision of this study 's estimates , various background variables were controlled for that were not related to treatment but could have some impact on the outcome . RESULTS The prevalence of soil-transmitted helminth ( STH ) infection was reduced in the treatment group ( n = 615 ) , with significant differences between treatment and control groups ( n = 575 ) in the levels of Ascaris and Trichuris . No impact was found on haemoglobin ( Hb ) levels , nor any significant impact on concentration levels or on educational test scores . CONCLUSION Decline in STH prevalence alone , in the absence of improved Hb status , produced no evidence of impact on concentration levels or educational test scores 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 r and omly 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 aim ed 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-r and omized 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 Introduction Enteric infections are common during the first years of life in low-income countries and contribute to growth faltering with long-term impairment of health and development . Water quality , sanitation , h and washing and nutritional interventions can independently reduce enteric infections and growth faltering . There is little evidence that directly compares the effects of these individual and combined interventions on diarrhoea and growth when delivered to infants and young children . The objective of the WASH Benefits study is to help fill this knowledge gap . Methods and analysis WASH Benefits includes two cluster-r and omised trials to assess improvements in water quality , sanitation , h and washing and child nutrition — alone and in combination — to rural households with pregnant women in Kenya and Bangladesh . Geographically matched clusters ( groups of household compounds in Bangladesh and villages in Kenya ) will be r and omised to one of six intervention arms or control . Intervention arms include water quality , sanitation , h and washing , nutrition , combined water+sanitation+h and washing ( WSH ) and WSH+nutrition . The studies will enrol newborn children ( N=5760 in Bangladesh and N=8000 in Kenya ) and measure outcomes at 12 and 24 months after intervention delivery . Primary outcomes include child length-for-age Z-scores and caregiver-reported diarrhoea . Secondary outcomes include stunting prevalence , markers of environmental enteropathy and child development scores ( verbal , motor and personal/social ) . We will estimate unadjusted and adjusted intention-to-treat effects using semiparametric estimators and permutation tests . Ethics and dissemination Study protocol s have been review ed and approved by human subjects review boards at the University of California , Berkeley , Stanford University , the International Centre for Diarrheal Disease Research , Bangladesh , the Kenya Medical Research Institute , and Innovations for Poverty Action . Independent data safety monitoring boards in each country oversee the trials . This study is funded by a grant from the Bill & Melinda Gates Foundation to the University of California , Berkeley . Registration Trial registration identifiers ( http://www . clinical trials.gov ) : NCT01590095 ( Bangladesh ) , NCT01704105 ( Kenya ) This r and omized double blind community trial was conducted on Ascaris infested children ( n = 85 ) aged 2 to 12 years and was aim ed to study the impact of deworming on nutritional status , in an urban slum of Dhaka , Bangladesh . The change of weight gain was significantly higher in children given anthelmintics than those given placebo ( 0.92 kg vs. 0.54 kg ) . A multiple linear regression model shows that after controlling sex , deworming and height were positively correlated while age and weight were negatively correlated with weight change Efficacy trials of antihelminthic therapies conducted in Africa have reported improvements in children 's growth , but nutritional evaluations of large-scale deworming programs are lacking . We evaluated the first-year effect on growth of a school-based deworming program in Zanzibar , where growth retardation occurs in school children . Children in four primary schools were given thrice-yearly mebendazole ( 500 mg ) and compared with children in four schools that received twice-yearly mebendazole and children in four non-program schools . Evaluation schools were r and omly selected and allocated to control , twice-yearly or thrice-yearly deworming .  Approximately 1000 children in each program group completed the 1-y follow-up . Children < 10 y old gained 0.27 kg more weight ( P < 0.05 ) and 0.13 cm more height ( P = 0.20 ) in the twice-yearly group , and 0 . 20 kg more weight ( P = 0.07 ) and 0.30 cm more height ( P < 0.01 ) in the thrice-yearly group , compared with the control group . Children < 10 y old with higher heights-for-age at baseline had higher weight and height gains in response to deworming . In children > /=10 y old , overall program effects on height or weight gains were not significant . But in this age range , younger boys had significant improvements in height gain with thrice-yearly deworming , and children with higher heights-for-age had greater improvements in weight gain with deworming . We conclude that the deworming program improved the growth  of school children , especially children who were younger and less stunted , but the improvements were small . More effective antihelminthic regimens or additional dietary or disease control interventions may be needed to substantially improve the growth of school children in areas such as Zanzibar We evaluated the effects of the  Zanzibar school-based deworming program  on the iron status of primary school children . Parasitologic and nutritional assessment s were carried out at baseline , 6 mo , and 12 mo in 4 nonprogram schools ( n = 1002 ) , 4 schools in which students received twice-yearly deworming ( n = 952 ) , and 4 schools in which students received thrice-yearly deworming ( n = 970 ) with 500 mg generic mebendazole .  Schools were r and omly selected for evaluation and allocated to program groups . Relative to no treatment , thrice-yearly deworming caused significant decreases in protoporphyrin concentrations and both deworming regimens caused marginally significant increases in serum ferritin concentrations . The average annual changes in protoporphyrin concentrations were -5.9 and -23.5 micromol/mol heme in the control and thrice-yearly deworming groups , respectively ( P < 0.001 ) . The average changes in ferritin concentration were 2.8 and 4.5 microg/L , respectively ( P = 0.07 ) . Deworming had no effect on annual hemoglobin change or prevalence of anemia . However , the relative risk of severe anemia ( hemoglobin < 70 g/L ) was 0.77 ( 95 % confidence limits : 0.39 , 1.51 ) in the twice-yearly deworming group and 0.45 ( 0.19 , 1.08 ) in the thrice-yearly deworming group . The effects on prevalence of high protoporphyrin values and incidence of moderate-to-severe anemia ( hemoglobin < 90 g/L ) were significantly greater in children with > 2000 hookworm eggs/g feces at baseline . We estimate that this deworming program prevented 1260 cases of moderate-to-severe anemia and 276 cases of severe anemia in a population of 30,000 schoolchildren in 1 y. Where hookworm is heavily endemic , deworming programs can improve iron status and prevent moderate and severe anemia , but deworming may be needed at least twice yearly Background There is considerable debate on the health impacts of soil-transmitted helminth infections . We assessed effects of deworming on physical fitness and strength of children in an area in Yunnan , People 's Republic of China , where soil-transmitted helminthiasis is highly endemic . Methodology The double-blind , r and omized , placebo-controlled trial was conducted between October 2011 and May 2012 . Children , aged 9–12 years , were treated with either triple-dose albendazole or placebo , and monitored for 6 months post-treatment . The Kato-Katz and Baermann techniques were used for the diagnosis of soil-transmitted helminth infections . Physical fitness was assessed with a 20-m shuttle run test , where the maximum  aerobic capacity within 1 min of exhaustive exercise ( VO2 max estimate ) and the number of 20-m laps completed were recorded . Physical strength was determined with grip strength and st and ing broad jump tests . Body height and weight , the sum of skinfolds , and hemoglobin levels were recorded as secondary outcomes . Principal Findings Children receiving triple-dose albendazole scored slightly higher in the primary and secondary outcomes than placebo recipients , but the difference lacked statistical significance . Trichuris trichiura-infected children had 1.6 ml kg−1 min−1 ( P = 0.02 ) less increase in their VO2 max estimate and completed 4.6 ( P = 0.04 ) fewer 20-m laps than at baseline compared to non-infected peers . Similar trends were detected in the VO2 max estimate and grip strength of children infected with hookworm and Ascaris lumbricoides , respectively . In addition , the increase in the VO2 max estimate from baseline was consistently higher in children with low-intensity T. trichiura and hookworm infections than in their peers with high-intensity infections of all soil-transmitted helminths ( range : 1.9–2.1 ml kg−1 min−1 ; all P<0.05 ) . Conclusions / Significance We found no strong evidence for significant improvements in physical fitness and anthropometric indicators due to deworming over a 6-month follow-up period . However , the negative effect of T. trichiura infections on physical fitness warrants further investigation Background Soil-transmitted helminths ( STH ) infect nearly 1.5 billion individuals globally , and contribute to poor physical and cognitive development in children . STH control programs typically consist of regular delivery of anthelminthic drugs , targeting school-aged children . Exp and ing STH control programs community-wide may improve STH control among school-aged children , and combining deworming with improvements to water , sanitation and hygiene ( WASH ) may further reduce transmission . The (S)WASH-D for Worms pilot study aims to compare the differential impact of integrated WASH and deworming programs when implemented at primary schools only versus when additionally implemented community-wide . Methodology /Principal findings A two-arm , non-r and omized cluster intervention study was conducted . Six communities were identified by partner WASH agencies and enrolled in the study . All communities received a  school-based WASH and deworming program  , while three additionally received a community-based WASH and deworming program .  STH infections were measured in school-aged children at baseline and six months after deworming . Over 90 % of eligible children were recruited for the study , of whom 92.3 % provided stool sample s at baseline and 88.9 % at follow-up . The school WASH intervention improved school sanitation , while the community WASH intervention reduced open defecation from 50.4 % ( 95 % CI 41.8–59.0 ) to 23.5 % ( 95 % CI 16.7–32.0 ) . There was a trend towards reduced odds of N. americanus infection among children who received the community-wide intervention ( OR 0.42 , 95 % CI 0.07–2.36 , p = 0.32 ) . Conclusions This pilot study provides proof of principle for testing the hypothesis that community-wide STH control programs have a greater impact on STH infections among children than school-based programs , and supports the rationale for conducting a full-scale cluster r and omized controlled trial . High recruitment and participation rates and successful implementation of school WASH programs demonstrate study feasibility and acceptability . However , eliminating open defecation remains a challenge ; ongoing work is required to develop community sanitation programs that achieve high and sustainable latrine coverage . Trial registration Australian New Zeal and Clinical Trials Registry ( ANZCTR ) Background Nutritional interventions targeting the critical growth and development period before two years of age can have the greatest impact on health trajectories over the life course . Compelling evidence has demonstrated that interventions investing in maternal health in the first 1000 days of life are beneficial for both mothers and their children . One such potential intervention is deworming integrated into maternal postpartum care in areas where soil-transmitted helminth ( STH ) infections are endemic . Methodology /Principal Findings From February to August 2014 , 1010 mother-infant pairs were recruited into a trial aim ed at assessing the effectiveness of maternal postpartum deworming on infant and maternal health outcomes . Following delivery , mothers were r and omly assigned to receive either single-dose 400 mg albendazole or placebo . Participants were followed-up at 1 and 6 months postpartum . There was no statistically significant difference in mean weight gain between infants in the experimental and control groups ( mean difference : -0.02 ; 95 % CI : -0.1 , 0.08 ) at 6 months of age . Further , deworming had no effect on measured infant morbidity indicators . However , ad hoc analyses restricted to mothers who tested positive for STHs at baseline suggest that infants of mothers in the experimental group had greater mean length gain in cm ( mean difference : 0.8 ; 95 % CI : 0.1 , 1.4 ) and length-for-age z-score ( mean difference : 0.5 ; 95 % CI : 0.2 , 0.8 ) at 6 months of age . Conclusions / Significance In a study population composed of both STH-infected and uninfected mothers , maternal postpartum deworming was insufficient to impact infant growth and morbidity indicators up to 6 months postpartum . Among STH-infected mothers , however , important improvements in infant length gain and length-for-age were observed . The benefits of maternal postpartum deworming should be further investigated in study population s having higher overall prevalences and intensities of STH infections and , in particular , where whipworm and hookworm infections are of public health concern . Trial registration Clinical Trials.gov ( NCT01748929 ) BACKGROUND A third of the 2·5 billion people worldwide without access to improved sanitation live in India , as do two-thirds of the 1·1 billion practising open defecation and a quarter of the 1·5 million who die annually from diarrhoeal diseases . We aim ed to assess the effectiveness of a rural sanitation intervention , within the context of the Government of India 's Total Sanitation Campaign , to prevent diarrhoea , soil-transmitted helminth infection , and child malnutrition . METHODS We did a cluster-r and omised controlled trial between May 20 , 2010 , and Dec 22 , 2013 , in 100 rural villages in Odisha , India . Households within villages were eligible if they had a child younger than 4 years or a pregnant woman . Villages were r and omly assigned ( 1:1 ) , with a computer-generated sequence , to undergo latrine promotion and construction or to receive no intervention ( control ) . R and omisation was stratified by administrative block to ensure an equal number of intervention and control villages in each block . Masking of participants was not possible because of the nature of the intervention . However , households were not told explicitly that the purpose of enrolment was to study the effect of a trial intervention , and the surveillance team was different from the intervention team . The primary endpoint was 7-day prevalence of reported diarrhoea in children younger than 5 years . We did intention-to-treat and per- protocol analyses . This trial is registered with Clinical Trials.gov , number NCT01214785 . FINDINGS We r and omly assigned 50 villages to the intervention group and 50 villages to the control group . There were 4586 households ( 24,969 individuals ) in intervention villages and 4894 households ( 25,982 individuals ) in control villages . The intervention increased mean village-level latrine coverage from 9 % of households to 63 % , compared with an increase from 8 % to 12 % in control villages . Health surveillance data were obtained from 1437 households with children younger than 5 years in the intervention group ( 1919 children younger than 5 years ) , and from 1465 households ( 1916 children younger than 5 years ) in the control group . 7-day prevalence of reported diarrhoea in children younger than 5 years was 8·8 % in the intervention group and 9·1 % in the control group ( period prevalence ratio 0·97 , 95 % CI 0·83 - 1·12 ) . 162  participants  died in the intervention group ( 11 children younger than 5 years ) and 151 died in the control group ( 13 children younger than 5 years ) . INTERPRETATION Increased latrine coverage is generally believed to be effective for reducing exposure to faecal pathogens and preventing disease ; however , our results show that this outcome can not be assumed . As efforts to improve sanitation are being undertaken worldwide , approaches should not only meet international coverage targets , but should also be implemented in a way that achieves uptake , reduces exposure , and delivers genuine health gains . FUNDING Bill & Melinda Gates Foundation , International Initiative for Impact Evaluation ( 3ie ) , and Department for International Development-backed SHARE Research Consortium at the London School of Hygiene & Tropical Medicine Background To control soil-transmitted helminth ( STH ) infections , the World Health Organization recommends school-based deworming programs with a health hygiene education component . The effect of such health hygiene interventions , however , has not been adequately studied . The objective of the present study was to determine the effectiveness of a health hygiene education intervention on the occurrence of STH re-infection four months post-de-worming . Methodology /Principal Findings An open-label pair-matched cluster-r and omized trial was conducted in Grade 5 schoolchildren of 18 primary schools ( 9 intervention and 9 control ) in the Peruvian Amazon . Baseline assessment included interview with a pre-tested question naire and collection of single stool specimens that were examined using the single Kato-Katz thick smear . All schoolchildren were then treated with single-dose albendazole ( 400 mg ) . Schoolchildren in intervention schools then received 1 ) an initial one hour in-class activity on health hygiene and sanitation and 30-minute refresher activities every two weeks over four months ; and 2 ) a half-day workshop for teachers and principals , while children in control schools did not . Four months later , STH infection was re-assessed in all schools by laboratory technologists blinded to intervention status . From April 21–October 20 , 2010 , a total of 1,089 schoolchildren ( 518 and 571 from intervention and control schools , respectively ) participated in this study . Intervention children scored significantly higher on all aspects of a test of STH-related knowledge compared with control children ( aOR = 18·4 ; 95 % CI : 12·7 to 26·6 ) . The intensity of Ascaris lumbricoides infection at follow-up was statistically significantly lower ( by 58 % ) in children in intervention schools compared with children in control schools ( aIRR = 0·42 ; 95 % CI = 0·21 to 0·85 ) . No significant changes in hookworm or Trichuris trichiura intensity were observed . Conclusions / Significance A school-based health hygiene education intervention was effective in increasing STH knowledge and in reducing Ascaris lumbricoides infection . The benefits of school-based periodic deworming programs are likely to be enhanced when a sustained health hygiene education intervention is integrated into school curricula
Interestingly , the pure replication shows very similar impacts of the intervention on children in the intervention schools irrespective of whether they took the deworming medicine or not.7 For Miguel and colleagues , they term this as ‘ indirect within-school effects ’ of deworming , but equally the effects could be due to the non-specific effects of the health promotion interventions in the intervention schools .
In addition , the study shows that allocation to the deworming group does not influence student progress , as the re- analysis shows clearly no evidence of a difference in examination performance between deworming and control groups.7,8 In the context of the global evidence base , there is only one other study that has examined school attendance with no obvious effect shown.4 Given all these uncertainties , we simply do n’t know if there is truly an effect on school attendance from the data , in taking all these factors into account formally in a GRADE analysis .4 But what weakens the case of deworming still further is that there is now quite good evidence of no effect for most of the main outcomes ( Figure 1 ) , including nutritional status , haemoglobin , cognition and school performance .
This is important because without these effects it seems implausible that deworming itself would have an independent effect on school attendance or economic development .
The World Bank , the Gates Foundation and the World Health Organization promote national child deworming programmes in developing countries.1 They assert these programmes will improve nutritional status , health and school performance , and hence contribute to economic growth .
Indeed , the World Health Organization states that deworming contributed to Japan ’s economic boom in the 1950s,2 and Nobel Laureates meeting in Copenhagen ranked deworming as the fourth most important intervention to solve the health problems of the whole world.3 Surprisingly , the evidence base for these cl aims from controlled studies is limited .
Another trial in India showed benefit , but subsequent trials in the same area failed to show an effect.4,9 So deworming may have helped in these exceptional , heavily infected , untreated population s from another decade , but this is scarcely a solid base for contemporary policy : public health nutrition has changed , worm burden has declined and this probably accounts for the lack of effect on biomedical outcomes in contemporary studies .10 We have been perplexed by the un question ing belief behind deworming in the advocates , and have found it is deep rooted in American history .