1
|
Gasparinho C, Kanjungo A, Zage F, Clemente I, Santos-Reis A, Brito M, Sousa-Figueiredo JC, Fortes F, Gonçalves L. Impact of Annual Albendazole versus Four-Monthly Test-and-Treat Approach of Intestinal Parasites on Children Growth-A Longitudinal Four-Arm Randomized Parallel Trial during Two Years of a Community Follow-Up in Bengo, Angola. Pathogens 2021; 10:309. [PMID: 33799921 PMCID: PMC8001871 DOI: 10.3390/pathogens10030309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 02/28/2021] [Accepted: 03/02/2021] [Indexed: 11/17/2022] Open
Abstract
Malnutrition and intestinal parasites continue to have serious impacts on growth and cognitive development of children in Angola. A longitudinal four-arm randomized parallel trial was conducted to investigate if deworming with a single annual dose of albendazole (annual-ALB) or a four-monthly test-and-treat (4TT) intestinal parasites approach at individual or household levels improve nutritional outcomes of pre-school children in Bengo province. Children with intestinal parasites (n = 121) were randomly assigned (1:1:1:1) to arm A1: annual-ALB*individual level; A2: annual-ALB*household level; A3: 4TT*individual; and A4: 4TT*household level. At baseline, 4, 8, 12, 16, 20, and 24 months of follow-up, growth was assessed by height, weight, height-for-age, weight-for-height, weight-for-age, and mid-upper arm circumference. Intention-to-treat analysis was done using non-parametric approach, mixed effect models, and generalized estimating equations (GEE). Initially, 57% and 26% of the children were infected by Giardia lamblia and Ascaris lumbricoides, respectively. This study did not show that a 4TT intestinal parasites approach results on better growth outcomes of children (height, weight, HAZ, WAZ, WHZ and MUACZ) when compared with annual ALB, with exception of height and WHZ using GEE model at 5% level. Positive temporal effects on most nutrition outcomes were observed. Implementing a longitudinal study in a poor setting is challenging and larger sample sizes and 'pure and clean' data are difficult to obtain. Nevertheless, learned lessons from this intensive study may contribute to future scientific research and to tailor multidisciplinary approaches to minimize malnutrition and infections in resource-poor countries.
Collapse
Affiliation(s)
- Carolina Gasparinho
- Centro de Investigação em Saúde de Angola (CISA), Rua Direita de Caxito, Caxito, Angola; (A.K.); (F.Z.); (I.C.); (M.B.); (J.C.S.-F.)
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), 1349-008 Lisbon, Portugal; (A.S.-R.); (F.F.)
| | - Aguinaldo Kanjungo
- Centro de Investigação em Saúde de Angola (CISA), Rua Direita de Caxito, Caxito, Angola; (A.K.); (F.Z.); (I.C.); (M.B.); (J.C.S.-F.)
| | - Félix Zage
- Centro de Investigação em Saúde de Angola (CISA), Rua Direita de Caxito, Caxito, Angola; (A.K.); (F.Z.); (I.C.); (M.B.); (J.C.S.-F.)
| | - Isabel Clemente
- Centro de Investigação em Saúde de Angola (CISA), Rua Direita de Caxito, Caxito, Angola; (A.K.); (F.Z.); (I.C.); (M.B.); (J.C.S.-F.)
| | - Ana Santos-Reis
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), 1349-008 Lisbon, Portugal; (A.S.-R.); (F.F.)
| | - Miguel Brito
- Centro de Investigação em Saúde de Angola (CISA), Rua Direita de Caxito, Caxito, Angola; (A.K.); (F.Z.); (I.C.); (M.B.); (J.C.S.-F.)
- Health and Technology Research Center (H&TRC), Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal
| | - José Carlos Sousa-Figueiredo
- Centro de Investigação em Saúde de Angola (CISA), Rua Direita de Caxito, Caxito, Angola; (A.K.); (F.Z.); (I.C.); (M.B.); (J.C.S.-F.)
| | - Filomeno Fortes
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), 1349-008 Lisbon, Portugal; (A.S.-R.); (F.F.)
- Faculdade de Medicina da Universidade Agostinho Neto, Luanda, Angola
| | - Luzia Gonçalves
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), 1349-008 Lisbon, Portugal; (A.S.-R.); (F.F.)
- Centro de Estatística e Aplicações da Universidade de Lisboa (CEAUL), Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisbon, Portugal
| |
Collapse
|
2
|
Sweeny AR, Clerc M, Pontifes PA, Venkatesan S, Babayan SA, Pedersen AB. Supplemented nutrition decreases helminth burden and increases drug efficacy in a natural host-helminth system. Proc Biol Sci 2021; 288:20202722. [PMID: 33468010 PMCID: PMC7893286 DOI: 10.1098/rspb.2020.2722] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/15/2020] [Indexed: 12/17/2022] Open
Abstract
Gastrointestinal (GI) helminths are common parasites of humans, wildlife, and livestock, causing chronic infections. In humans and wildlife, poor nutrition or limited resources can compromise an individual's immune response, predisposing them to higher helminth burdens. This relationship has been tested in laboratory models by investigating infection outcomes following reductions of specific nutrients. However, much less is known about how diet supplementation can impact susceptibility to infection, acquisition of immunity, and drug efficacy in natural host-helminth systems. We experimentally supplemented the diet of wood mice (Apodemus sylvaticus) with high-quality nutrition and measured resistance to the common GI nematode Heligmosomoides polygyrus. To test whether diet can enhance immunity to reinfection, we also administered anthelmintic treatment in both natural and captive populations. Supplemented wood mice were more resistant to H. polygyrus infection, cleared worms more efficiently after treatment, avoided a post-treatment infection rebound, produced stronger general and parasite-specific antibody responses, and maintained better body condition. In addition, when applied in conjunction with anthelmintic treatment, supplemented nutrition significantly reduced H. polygyrus transmission potential. These results show the rapid and extensive benefits of a well-balanced diet and have important implications for both disease control and wildlife health under changing environmental conditions.
Collapse
Affiliation(s)
- Amy R. Sweeny
- Institute of Evolutionary Biology and Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Melanie Clerc
- MRC Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Paulina A. Pontifes
- Departamento de Etología, Fauna Silvestre y Animales de Laboratorio, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Avenida Ciudad Universitaria 3000, CP 04510 Coyoacán, Ciudad de México, México
| | - Saudamini Venkatesan
- Institute of Evolutionary Biology and Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Simon A. Babayan
- Institute of Biodiversity Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
| | - Amy B. Pedersen
- Institute of Evolutionary Biology and Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| |
Collapse
|
3
|
Jones TPW, Hart JD, Kalua K, Bailey RL. A prevalence survey of enteral parasites in preschool children in the Mangochi District of Malawi. BMC Infect Dis 2019; 19:838. [PMID: 31604429 PMCID: PMC6956491 DOI: 10.1186/s12879-019-4439-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 09/04/2019] [Indexed: 11/10/2022] Open
Abstract
Background Helminthic and protozoan infections are common, particularly in low- or middle-income countries. Although an association between parasite carriage and markers of poor growth have been shown in some studies, systematic reviews have suggested only a modest impact of clearing carriage. The prevalence of these pathogens and the effect that they have on growth in preschool children has never been investigated in Malawi. Methods One hundred ninety-three children aged 0–72 months were randomly recruited from rural villages in the Mangochi district of Malawi. Formol-ether concentration was performed on stool and the samples examined with a light microscope. Anthropometric data was taken for each child and the haemoglobin measured with a point of care test. Results The mean age of the children was 2 years 4 months. Overall prevalence of intestinal parasite infection was 37.3%. Protozoa were found in 28.5% of children, while helminths were found in 8.8%. The most commonly found organisms were Giardia lambia (12.4%), Entamoeba coli (10.4%) and Hookworm species (3.6%). Stunting was seen in 47.8% of children, 12.9% were underweight and 5.0% were wasted. No significant association was found between markers of poor growth and infection with any intestinal parasite. Conclusions We found that prevalence of helminth infection was low in preschool children living in the Mangochi district compared to international standards. However a significant proportion of the preschool population are infected with protozoa, particularly Giardia lambia. In this cohort, despite a significant prevalence of stunting, helminth infection was not significantly associated with any markers of poor growth. The significance of protozoal carriage and contribution to growth restriction in this context creates further avenues for future research.
Collapse
Affiliation(s)
- Timothy P W Jones
- Department of Infectious Disease and Microbiology, Royal Free Hospital, Pond Street, London, NW3 2QG, UK
| | - John D Hart
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Khumbo Kalua
- Department of Ophthalmology, University of Malawi, College of Medicine, Queen Elizabeth Central Hospital, P.O. Box E180, Blantyre, Malawi. .,Blantyre Institute for Community Ophthalmology, Lions Sight First Eye Hospital, Queen Elizabeth Central Hospital, P.O. Box E180, Blantyre, Malawi.
| | - Robin L Bailey
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| |
Collapse
|
4
|
Taylor‐Robinson DC, Maayan N, Donegan S, Chaplin M, Garner P. Public health deworming programmes for soil-transmitted helminths in children living in endemic areas. Cochrane Database Syst Rev 2019; 9:CD000371. [PMID: 31508807 PMCID: PMC6737502 DOI: 10.1002/14651858.cd000371.pub7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND The World Health Organization (WHO) recommends treating all school children at regular intervals with deworming drugs in areas where helminth infection is common. Global advocacy organizations claim routine deworming has substantive health and societal effects beyond the removal of worms. In this update of the 2015 edition we included six new trials, additional data from included trials, and addressed comments and criticisms. OBJECTIVES To summarize the effects of public health programmes to regularly treat all children with deworming drugs on child growth, haemoglobin, cognition, school attendance, school performance, physical fitness, and mortality. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; Embase; LILACS; the metaRegister of Controlled Trials (mRCT); reference lists; and registers of ongoing and completed trials up to 19 September 2018. SELECTION CRITERIA We included randomized controlled trials (RCTs) and quasi-RCTs that compared deworming drugs for soil-transmitted helminths (STHs) with placebo or no treatment in children aged 16 years or less, reporting on weight, height, haemoglobin, and formal tests of cognition. We also sought data on other measures of growth, school attendance, school performance, physical fitness, and mortality. DATA COLLECTION AND ANALYSIS At least two review authors independently assessed the trials for inclusion, risk of bias, and extracted data. We analysed continuous data using the mean difference (MD) with 95% confidence intervals (CIs). Where data were missing, we contacted trial authors. We stratified the analysis based on the background burden of STH infection. We used outcomes at time of longest follow-up. We assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS We identified 51 trials, including 10 cluster-RCTs, that met the inclusion criteria. One trial evaluating mortality included over one million children, and the remaining 50 trials included a total of 84,336 participants. Twenty-four trials were in populations categorized as high burden, including nine trials in children selected because they were helminth-stool positive; 18 with intermediate burden; and nine as low burden.First or single dose of deworming drugsFourteen trials reported on weight after a single dose of deworming drugs (4970 participants, 14 RCTs). The effects were variable. There was little or no effect in studies conducted in low and intermediate worm burden groups. In the high-burden group, there was little or no effect in most studies, except for a large effect detected from one study area in Kenya reported in two trials carried out over 30 years ago. These trials result in qualitative heterogeneity and uncertainty in the meta-analysis across all studies (I2 statistic = 90%), with GRADE assessment assessed as very low-certainty, which means we do not know if a first dose or single dose of deworming impacts on weight.For height, most studies showed little or no effect after a single dose, with one of the two trials in Kenya from 30 years ago showing a large average difference (2621 participants, 10 trials, low-certainty evidence). Single dose probably had no effect on average haemoglobin (MD 0.10 g/dL, 95% CI 0.03 lower to 0.22 higher; 1252 participants, five trials, moderate-certainty evidence), or on average cognition (1596 participants, five trials, low-certainty evidence). The data are insufficient to know if there is an effect on school attendance and performance (304 participants, one trial, low-certainty evidence), or on physical fitness (280 participants, three trials, very low-certainty evidence). No trials reported on mortality.Multiple doses of deworming drugsThe effect of regularly treating children with deworming drugs given every three to six months on weight was reported in 18 trials, with follow-up times of between six months and three years; there was little or no effect on average weight in all but two trials, irrespective of worm prevalence-intensity. The two trials with large average weight gain included one in the high burden area in Kenya carried out over 30 years ago, and one study from India in a low prevalence area where subsequent studies in the same area did not show an effect. This heterogeneity causes uncertainty in any meta-analysis (I2 = 78%). Post-hoc analysis excluding trials published prior to 2000 gave an estimate of average difference in weight gain of 0.02 kg (95%CI from 0.04 kg loss to 0.08 gain, I2 = 0%). Thus we conclude that we do not know if repeated doses of deworming drugs impact on average weight, with a fewer older studies showing large gains, and studies since 2000 showing little or no average gain.Regular treatment probably had little or no effect on the following parameters: average height (MD 0.02 cm higher, 95% CI 0.09 lower to 0.13 cm higher; 13,700 participants, 13 trials, moderate-certainty evidence); average haemoglobin (MD 0.01 g/dL lower; 95% CI 0.05 g/dL lower to 0.07 g/dL higher; 5498 participants, nine trials, moderate-certainty evidence); formal tests of cognition (35,394 participants, 8 trials, moderate-certainty evidence); school performance (34,967 participants, four trials, moderate-certainty evidence). The evidence assessing an effect on school attendance is inconsistent, and at risk of bias (mean attendance 2% higher, 95% CI 5% lower to 8% higher; 20,650 participants, three trials, very low-certainty evidence). No trials reported on physical fitness. No effect was shown on mortality (1,005,135 participants, three trials, low-certainty evidence). AUTHORS' CONCLUSIONS Public health programmes to regularly treat all children with deworming drugs do not appear to improve height, haemoglobin, cognition, school performance, or mortality. We do not know if there is an effect on school attendance, since the evidence is inconsistent and at risk of bias, and there is insufficient data on physical fitness. Studies conducted in two settings over 20 years ago showed large effects on weight gain, but this is not a finding in more recent, larger studies. We would caution against selecting only the evidence from these older studies as a rationale for contemporary mass treatment programmes as this ignores the recent studies that have not shown benefit.The conclusions of the 2015 edition have not changed in this update.
Collapse
Affiliation(s)
| | - Nicola Maayan
- Independent consultantLondonUK
- Cochrane ResponseLondonUK
| | - Sarah Donegan
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolMerseysideUKL3 5QA
| | - Marty Chaplin
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolMerseysideUKL3 5QA
| | - Paul Garner
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolMerseysideUKL3 5QA
| | | |
Collapse
|
5
|
Drimia indica: A Plant Used in Traditional Medicine and Its Potential for Clinical Uses. ACTA ACUST UNITED AC 2019; 55:medicina55060255. [PMID: 31181697 PMCID: PMC6630810 DOI: 10.3390/medicina55060255] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 12/27/2022]
Abstract
Drimia indica (Roxb.) Jessop (Asparagaceae) is a reputed Ayurvedic medicine for a number of therapeutic benefits, including for cardiac diseases, indigestion, asthma, dropsy, rheumatism, leprosy, and skin ailments. The present work aimed to critically and extensively review its traditional uses, phytochemistry, pharmacology, toxicology, and taxonomy together with the mechanisms of action of selected extracts of D. indica. A systematic literature survey from scientific databases such as PubMed, Scopus, and Web of Science as well as from some textbooks and classical texts was conducted. The plant, mainly its bulb, contains various bioactive constituents, such as alkylresorcinols, bufadienolides, phytosterols, and flavonoids. Various scientific studies have proven that the plant has anthelmintic, anticancer, antidiabetic, antimicrobial, antioxidant, and wound healing activities. The present work concludes that D. indica has the potential to treat various diseases, mainly microbial infections. This review also suggests that bufadienolides, flavonoids, and steroids might be responsible for its bioactive potential.
Collapse
|
6
|
Bakarman MA, Hegazi MA, Butt NS. Prevalence, Characteristics, Risk Factors, and Impact of Intestinal Parasitic Infections on School Children in Jeddah, Western Saudi Arabia. J Epidemiol Glob Health 2019; 9:81-87. [PMID: 30932395 PMCID: PMC7310768 DOI: 10.2991/jegh.k.190219.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 01/16/2018] [Indexed: 11/02/2022] Open
Abstract
Intestinal Parasitic Infections (IPIs) are a major public health problem worldwide, especially among children with a need for periodical evaluation of prevalence and risk factors to adopt an appropriate prevention strategy. This cross-sectional prospective study was conducted to identify prevalence, risk factors, characteristics, and impact of IPIs on school children in different regions of Jeddah, Saudi Arabia. Children were recruited from randomly selected schools. Questionnaires were distributed to students and filled by their parents to collect relevant information about sociodemographic, environmental, and hygienic living conditions. Stool samples and anthropometric measurements as indicators of nutritional status were collected from students who agreed to participate in the study. Fecal samples were examined by direct smear and formol-ether concentration method. Out of 581 collected stool samples, only 31 (5.3%) samples were positive for IPIs especially Blastocystis hominis (10 samples) and Giardia lamblia (six samples). The only two significant risk factors associated with IPIs were drinking water from tanks [odds ratio (OR): 3.35, 95% confidence interval (CI): 1.60-6.99, p = 0.001] and washing hands with only water (OR: 2.63, 95% CI: 1.17-5.93, p = 0.03). There was no significant impact of IPIs on growth parameters or level of children's academic performance.
Collapse
Affiliation(s)
- Marwan A Bakarman
- Department of Family and Community Medicine, Faculty of Medicine in Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Moustafa A Hegazi
- Department of Pediatrics, Faculty of Medicine in Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Pediatrics, Mansoura University Children's Hospital, Mansoura, Egypt
| | - Nadeem S Butt
- Department of Family and Community Medicine, Faculty of Medicine in Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia
| |
Collapse
|
7
|
Abraham D, Kaliappan SP, Walson JL, Rao Ajjampur SS. Intervention strategies to reduce the burden of soil-transmitted helminths in India. Indian J Med Res 2018; 147:533-544. [PMID: 30168484 PMCID: PMC6118140 DOI: 10.4103/ijmr.ijmr_881_18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Soil-transmitted helminth (STH) infections continue to be a major global cause of morbidity, with a large proportion of the burden of STH infections occurring in India. In addition to direct health impacts of these infections, including anaemia and nutritional deficiencies in children, these infections also significantly impact economic development, as a result of delays in early childhood cognitive development and future income earning potential. The current World Health Organization strategy for STH is focused on morbidity control through the application of mass drug administration to all pre-school-aged and school-aged children. In India, the control of STH-related morbidity requires mobilization of significant human and financial resources, placing additional burdens on limited public resources. Infected adults and untreated children in the community act as a reservoir of infection by which treated children get rapidly reinfected. As a result, deworming programmes will need to be sustained indefinitely in the absence of other strategies to reduce reinfection, including water, hygiene and sanitation interventions (WASH). However, WASH interventions require sustained effort by the government or other agencies to build infrastructure and to promote healthy behavioural modifications, and their effectiveness is often limited by deeply entrenched cultural norms and behaviours. Novel strategies must be explored to provide a lasting solution to the problem of STH infections in India other than the indefinite provision of deworming for morbidity control.
Collapse
Affiliation(s)
- Dilip Abraham
- Wellcome Trust Research Laboratory, Division of Gastrointestinal Sciences, Christian Medical College, Vellore, India
| | | | - Judd L Walson
- Department of Global Health, Medicine (Infectious Disease), Paediatrics & Epidemiology, University of Washington, Seattle, USA; DeWorm3, Division of Life Sciences, Natural History Museum, London, UK
| | - Sitara Swarna Rao Ajjampur
- Wellcome Trust Research Laboratory, Division of Gastrointestinal Sciences, Christian Medical College, Vellore, India
| |
Collapse
|
8
|
Liu C, Lu L, Zhang L, Luo R, Sylvia S, Medina A, Rozelle S, Smith DS, Chen Y, Zhu T. Effect of Deworming on Indices of Health, Cognition, and Education Among Schoolchildren in Rural China: A Cluster-Randomized Controlled Trial. Am J Trop Med Hyg 2018; 96:1478-1489. [PMID: 28093533 DOI: 10.4269/ajtmh.16-0354] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
AbstractSoil-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 reviews examining the impact of deworming drugs for STH on nutrition, hemoglobin, and school performance found that randomized 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.
Collapse
Affiliation(s)
- Chengfang Liu
- China Center for Agricultural Policy, School of Advanced Agricultural Sciences, Peking University, Beijing, China
| | - Louise Lu
- Freeman Spogli Institute, Stanford University, Stanford, California.,Yale University School of Medicine, New Haven, Connecticut
| | - Linxiu Zhang
- Center for Chinese Agricultural Policy, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Renfu Luo
- China Center for Agricultural Policy, School of Advanced Agricultural Sciences, Peking University, Beijing, China
| | - Sean Sylvia
- School of Economics, Renmin University of China, Beijing, China
| | - Alexis Medina
- Freeman Spogli Institute, Stanford University, Stanford, California
| | - Scott Rozelle
- Freeman Spogli Institute, Stanford University, Stanford, California
| | | | - Yingdan Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Tingjun Zhu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| |
Collapse
|
9
|
Deichsel EL, Tickell KD, Long JE, Jumbe NL, Rowhani-Rahbar A, Walson JL. Challenges in Assessing Combined Interventions to Promote Linear Growth. Am J Trop Med Hyg 2018; 98:1220-1223. [PMID: 29436344 PMCID: PMC5953351 DOI: 10.4269/ajtmh.17-0212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Despite the recognition of stunting as a public health priority, nutritional and nonnutritional interventions to reduce or prevent linear growth failure have demonstrated minimal impact. Investigators and policymakers face several challenges that limit their ability to assess the potential benefits of combining available interventions into a linear growth promotion package. We use two common but very different interventions, deworming and multiple micronutrient supplements, to illustrate barriers to recommending an optimal linear growth promotion package based on the currently available literature. These challenges suggest that combining individual- and population-based as well as model-based approaches would complement existing research using systematic review, meta-analysis, and factorial randomized trials, and help integrate existing fields of research to inform the development of optimal linear growth promotion packages for children living in resource-limited settings.
Collapse
Affiliation(s)
- Emily L Deichsel
- Department of Epidemiology, University of Washington, Seattle, Washington
| | - Kirkby D Tickell
- Department of Global Health, University of Washington, Seattle, Washington.,Childhood Acute Illness & Nutrition Network (CHAIN), Nairobi, Kenya
| | - Jessica E Long
- Department of Epidemiology, University of Washington, Seattle, Washington
| | | | - Ali Rowhani-Rahbar
- Department of Epidemiology, University of Washington, Seattle, Washington.,Department of Pediatrics, University of Washington, Seattle, Washington
| | - Judd L Walson
- Department of Epidemiology, University of Washington, Seattle, Washington.,Department of Global Health, University of Washington, Seattle, Washington.,Department of Medicine, University of Washington, Seattle, Washington.,Department of Pediatrics, University of Washington, Seattle, Washington.,Childhood Acute Illness & Nutrition Network (CHAIN), Nairobi, Kenya
| |
Collapse
|
10
|
Pabalan N, Singian E, Tabangay L, Jarjanazi H, Boivin MJ, Ezeamama AE. Soil-transmitted helminth infection, loss of education and cognitive impairment in school-aged children: A systematic review and meta-analysis. PLoS Negl Trop Dis 2018; 12:e0005523. [PMID: 29329288 PMCID: PMC5766095 DOI: 10.1371/journal.pntd.0005523] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 10/01/2017] [Indexed: 02/06/2023] Open
Abstract
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.
Collapse
Affiliation(s)
- Noel Pabalan
- Center for Research and Development, Angeles University Foundation, Angeles City, Philippines
| | - Eloisa Singian
- Department of Medical Technology, College of Allied Medical Professions, Angeles University Foundation, Angeles, Philippines
| | - Lani Tabangay
- Department of Biological Sciences, Angeles University Foundation, Angeles City, Philippines
| | - Hamdi Jarjanazi
- Environmental Monitoring and Reporting Branch, Biomonitoring Unit, Ontario Ministry of the Environment and Climate Change, Toronto, Ontario, Canada
| | - Michael J. Boivin
- Department of Psychiatry, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, United States of America
| | - Amara E. Ezeamama
- Department of Psychiatry, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, United States of America
| |
Collapse
|
11
|
Duijster D, Monse B, Dimaisip-Nabuab J, Djuharnoko P, Heinrich-Weltzien R, Hobdell M, Kromeyer-Hauschild K, Kunthearith Y, Mijares-Majini MC, Siegmund N, Soukhanouvong P, Benzian H. 'Fit for school' - a school-based water, sanitation and hygiene programme to improve child health: Results from a longitudinal study in Cambodia, Indonesia and Lao PDR. BMC Public Health 2017; 17:302. [PMID: 28381246 PMCID: PMC5382467 DOI: 10.1186/s12889-017-4203-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/25/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The Fit for School (FIT) programme integrates school health and Water, Sanitation and Hygiene interventions, which are implemented by the Ministries of Education in four Southeast Asian countries. This paper describes the findings of a Health Outcome Study, which aimed to assess the two-year effect of the FIT programme on the parasitological, weight, and oral health status of children attending schools implementing the programme in Cambodia, Indonesia and Lao PDR. METHODS The study was a non-randomized clustered controlled trial with a follow-up period of two years. The intervention group consisted of children attending public elementary schools implementing the FIT programme, including daily group handwashing with soap and toothbrushing with fluoride toothpaste, biannual school-based deworming; as well as construction of group handwashing facilities. Control schools implemented the regular government health education curriculum and biannual deworming. Per school, a random selection of six to seven-year-old grade-one students was drawn. Data on parasitological infections, anthropometric measurements, dental caries, odontogenic infections and sociodemographic characteristics were collected at baseline and at follow-up (24 months later). Data were analysed using the χ2-test, Mann Whitney U-test and multilevel logistic and linear regression. RESULTS A total of 1847 children (mean age = 6.7 years, range 6.0-8.0 years) participated in the baseline survey. Of these, 1499 children were available for follow-up examination - 478, 486 and 535 children in Cambodia, Indonesia and Lao PDR, respectively. In all three countries, children in intervention schools had a lower increment in the number of decayed, missing and filled permanent teeth between baseline and follow-up, in comparison to children in controls schools. The preventive fraction was 24% at average. The prevalence of soil-transmitted helminth infection (which was unexpectedly low at baseline), the prevalence of thinness and the prevalence of odontogenic infections did not significantly differ between baseline and follow-up, nor between intervention and control schools. CONCLUSIONS The study found that the FIT programme significantly contributed to the prevention of dental caries in children. This study describes the challenges, learnings and, moreover, the importance of conducting real-life implementation research to evaluate health programmes to transform school settings into healthy learning environments for children. The study is retrospectively registered with the German Clinical Trials Register, University of Freiburg (Trial registration number: DRKS00004485, date of registration: 26th of February, 2013).
Collapse
Affiliation(s)
- Denise Duijster
- Department of Social Dentistry, Academic Centre for Dentistry Amsterdam, Gustav Mahlerlaan 3004, 1081LA, Amsterdam, The Netherlands. .,Department of Epidemiology and Public Health, University College London, Torrington Place 1-19, London, WC1E 6BT, UK.
| | - Bella Monse
- Gesellschaft für Internationale Zusammenarbeit (GIZ), L.P. Leviste cor Rufino Street, Makati City, Metro Manila, Philippines
| | - Jed Dimaisip-Nabuab
- Gesellschaft für Internationale Zusammenarbeit (GIZ), L.P. Leviste cor Rufino Street, Makati City, Metro Manila, Philippines
| | - Pantjawidi Djuharnoko
- Social Basic Services Bureau of West Java, Governor's Office, Jl. Diponegoro No. 22, Citarum, Bandung Wetan, Bandung, West Java, 40115, Indonesia
| | - Roswitha Heinrich-Weltzien
- Department of Preventive Dentistry and Pediatric Dentistry, University Hospital Jena, Friedrich Schiller University Jena, Bachstraße 18, 07743, Jena, Germany
| | - Martin Hobdell
- Department of Epidemiology and Public Health, University College London, Torrington Place 1-19, London, WC1E 6BT, UK
| | - Katrin Kromeyer-Hauschild
- Institute of Human Genetics, University Hospital Jena, Friedrich Schiller University Jena, Kollegiengasse 10, 07740, Jena, Germany
| | - Yung Kunthearith
- Department of School Health of the Ministry of Education, Youth and Sport of the Kingdom of Cambodia, Street 380, Chao Ponheahok Primary School, BKK1, Khann Chamkarmorn, Phnom Penh, Cambodia
| | - Maria Carmela Mijares-Majini
- Gesellschaft für Internationale Zusammenarbeit (GIZ), L.P. Leviste cor Rufino Street, Makati City, Metro Manila, Philippines
| | - Nicole Siegmund
- Gesellschaft für Internationale Zusammenarbeit (GIZ), L.P. Leviste cor Rufino Street, Makati City, Metro Manila, Philippines
| | - Panith Soukhanouvong
- Department of Preschool and Primary Education, Ministry of Education and Sports, Ministry of Education Building No 1, Lane Xang Ave, P.O. Box 067, Vientiane Capital, Laos
| | - Habib Benzian
- Department of Epidemiology and Health Promotion, College of Dentistry, New York University, 433 First Avenue, New York, NY, 10010, USA
| |
Collapse
|
12
|
Campbell SJ, Nery SV, Doi SA, Gray DJ, Soares Magalhães RJ, McCarthy JS, Traub RJ, Andrews RM, Clements ACA. Complexities and Perplexities: A Critical Appraisal of the Evidence for Soil-Transmitted Helminth Infection-Related Morbidity. PLoS Negl Trop Dis 2016; 10:e0004566. [PMID: 27196100 PMCID: PMC4873196 DOI: 10.1371/journal.pntd.0004566] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Soil-transmitted helminths (STH) have acute and chronic manifestations, and can result in lifetime morbidity. Disease burden is difficult to quantify, yet quantitative evidence is required to justify large-scale deworming programmes. A recent Cochrane systematic review, which influences Global Burden of Disease (GBD) estimates for STH, has again called into question the evidence for deworming benefit on morbidity due to STH. In this narrative review, we investigate in detail what the shortfalls in evidence are. METHODOLOGY/PRINCIPAL FINDINGS We systematically reviewed recent literature that used direct measures to investigate morbidity from STH and we critically appraised systematic reviews, particularly the most recent Cochrane systematic review investigating deworming impact on morbidity. We included six systematic reviews and meta-analyses, 36 literature reviews, 44 experimental or observational studies, and five case series. We highlight where evidence is insufficient and where research needs to be directed to strengthen morbidity evidence, ideally to prove benefits of deworming. CONCLUSIONS/SIGNIFICANCE Overall, the Cochrane systematic review and recent studies indicate major shortfalls in evidence for direct morbidity. However, it is questionable whether the systematic review methodology should be applied to STH due to heterogeneity of the prevalence of different species in each setting. Urgent investment in studies powered to detect direct morbidity effects due to STH is required.
Collapse
Affiliation(s)
- Suzy J. Campbell
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| | - Susana V. Nery
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| | - Suhail A. Doi
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| | - Darren J. Gray
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
- Molecular Parasitology Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Ricardo J. Soares Magalhães
- Children's Health and Environment Program, Queensland Children's Medical Research Institute, The University of Queensland, Brisbane, Queensland, Australia
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia
| | - James S. McCarthy
- School of Population Health, University of Queensland, Brisbane, Queensland, Australia
- Clinical Tropical Medicine Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Rebecca J. Traub
- Faculty of Veterinary and Agricultural Science, The University of Melbourne, Melbourne, Victoria, Australia
| | - Ross M. Andrews
- Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | - Archie C. A. Clements
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| |
Collapse
|
13
|
Montresor A, Addiss D, Albonico M, Ali SM, Ault SK, Gabrielli AF, Garba A, Gasimov E, Gyorkos T, Jamsheed MA, Levecke B, Mbabazi P, Mupfasoni D, Savioli L, Vercruysse J, Yajima A. Methodological Bias Can Lead the Cochrane Collaboration to Irrelevance in Public Health Decision-Making. PLoS Negl Trop Dis 2015; 9:e0004165. [PMID: 26492178 PMCID: PMC4619606 DOI: 10.1371/journal.pntd.0004165] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Antonio Montresor
- Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - David Addiss
- Children Without Worms, Task Force for Global Health, Decatur, Georgia, United States of America
| | - Marco Albonico
- WHO Collaborating Centre for Neglected Tropical Diseases, Public Health Laboratory Ivo de Carneri, Zanzibar, United Republic of Tanzania
| | - Said Mohammed Ali
- WHO Collaborating Centre for Neglected Tropical Diseases, Public Health Laboratory Ivo de Carneri, Zanzibar, United Republic of Tanzania
| | - Steven K. Ault
- Neglected Infectious Diseases, Pan American Health Organization, World Health Regional Office for the Americas, Washington, DC, United States of America
| | - Albis-Francesco Gabrielli
- Neglected Tropical Diseases, World Health Organization Regional Office for the Eastern Mediterranean, Cairo, Egypt
| | - Amadou Garba
- Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Elkhan Gasimov
- Malaria, Other Vectorborne and Parasitic Diseases, World Health Organization Regional Office for Europe, Copenhagen, Denmark
| | - Theresa Gyorkos
- WHO Collaborating Centre for Research and Training in Parasite Epidemiology and Control, Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Mohamed Ahmed Jamsheed
- Vector-Borne and Neglected Tropical Diseases Control, World Health Organization Regional Office for South-East Asia, New Delhi, India
| | - Bruno Levecke
- WHO Collaborating Centre for the Monitoring of Anthelminthic Drug Efficacy for Soil-Transmitted Helminthiasis, Department of Virology, Parasitology and Immunology, University of Ghent, Ghent, Belgium
| | - Pamela Mbabazi
- Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Denise Mupfasoni
- Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Lorenzo Savioli
- Global Schistosomiasis Alliance and Public Health Laboratory Ivo de Carneri, Zanzibar, United Republic of Tanzania
| | - Jozef Vercruysse
- WHO Collaborating Centre for the Monitoring of Anthelminthic Drug Efficacy for Soil-Transmitted Helminthiasis, Department of Virology, Parasitology and Immunology, University of Ghent, Ghent, Belgium
| | - Aya Yajima
- Malaria, Other Vectorborne and Parasitic Diseases, World Health Organization, Regional Office for Western Pacific, Manila, Philippines
| |
Collapse
|
14
|
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. PLoS Negl Trop Dis 2015; 9:e0004020. [PMID: 26426270 PMCID: PMC4591279 DOI: 10.1371/journal.pntd.0004020] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/30/2015] [Indexed: 11/19/2022] Open
Abstract
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 randomized, 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 randomly 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 ClinicalTrials.gov (NCT01314937) The World Health Organization recommends starting population-based deworming interventions as of 12 months of age where intestinal worm infection is common; however, little is known about the benefits in early preschool-age children. We conducted a clinical trial to determine the effect of deworming on growth in one-year-old children in Peru. Participating children were randomly assigned to: 1) deworming at 12 months of age; 2) deworming at 18 months of age; 3) deworming at 12 and 18 months of age; or 4) no deworming (i.e. control group). A total of 1760 children were enrolled between September 2011 and June 2012, and followed up for one year. Overall, with one year of follow-up, no effect of deworming on growth could be detected in this population of preschool-age children. The potential benefit of the intervention may have been affected by low baseline infection prevalence and/or low compliance to the randomly assigned intervention. Additional research is required to overcome these challenges and to contribute to strengthening the evidence base on deworming.
Collapse
|
15
|
Abstract
• On the basis of research evidence, worm infections are important global child health conditions causing chronic disability that lasts from childhood into adulthood (Table 1). (2)(3) Evidence Quality: B • On the basis of research evidence, the major worm infections found in developing countries include ascariasis, trichuriasis, hookworm infection, and schistosomiasis; toxocariasis, enterobiasis, and cysticercosis are also found in poor regions of North America and Europe. (4)(9)(13) Evidence Quality: B • On the basis of expert consensus, children and adolescents are often vulnerable to acquiring large numbers of worms, ie, high-intensity infections (Fig 1)(21)(22)(23) Evidence Quality: D • On the basis of expert consensus and research evidence, moderate and heavy worm burdens cause increased morbidity because of growth and intellectual stunting in children and adolescents. Many of these effects may result from helminth-induced malnutrition. (21)(22)(23) Evidence Quality: C • On the basis of expert consensus and research evidence, worm infections are also commonly associated with eosinophilia. (48) (49) Evidence Quality: B • On the basis of research evidence as well as consensus, helminthes can cause inflammation in the lung (asthma), gastrointestinal tract (enteritis and colitis), liver (hepatitis and fibrosis), and urogenital tract. (7)(21)(22)(23)(27)(28)(40)(41)(43) Evidence Quality: B • On the basis of research evidence, microscopy techniques for diagnosis of worm infections in children often exhibit suboptimal sensitivities and specificities, necessitating new or improved diagnostic modalities such as polymerase chain reaction. (54)(55) Evidence Quality: A • On the basis of research evidence and expert consensus, mass drug administration (“preventive chemotherapy”) has becomea standard practice for ministries of health in low- and middle-income countries to control intestinal helminth infections and schistosomiasis. (67)(68) Evidence Quality: B.
Collapse
Affiliation(s)
- Jill E Weatherhead
- Department of Pediatrics (Sections of Infectious Diseases and Tropical Medicine), National School of Tropical Medicine, Baylor College of Medicine, Houston, TX. Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, Houston, TX
| | - Peter J Hotez
- Department of Pediatrics (Sections of Infectious Diseases and Tropical Medicine), National School of Tropical Medicine, Baylor College of Medicine, Houston, TX. Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, Houston, TX
| |
Collapse
|
16
|
Taylor‐Robinson DC, Maayan N, Soares‐Weiser K, Donegan S, Garner P. Deworming drugs for soil-transmitted intestinal worms in children: effects on nutritional indicators, haemoglobin, and school performance. Cochrane Database Syst Rev 2015; 2015:CD000371. [PMID: 26202783 PMCID: PMC4523932 DOI: 10.1002/14651858.cd000371.pub6] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The World Health Organization (WHO) recommends treating all school children at regular intervals with deworming drugs in areas where helminth infection is common. As the intervention is often claimed to have important health, nutrition, and societal effects beyond the removal of worms, we critically evaluated the evidence on benefits. OBJECTIVES To summarize the effects of giving deworming drugs to children to treat soil-transmitted helminths on weight, haemoglobin, and cognition; and the evidence of impact on physical well-being, school attendance, school performance, and mortality. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register (14 April 2015); Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library (2015, Issue 4); MEDLINE (2000 to 14 April 2015); EMBASE (2000 to 14 April 2015); LILACS (2000 to 14 April 2015); the metaRegister of Controlled Trials (mRCT); and reference lists, and registers of ongoing and completed trials up to 14 April 2015. SELECTION CRITERIA We included randomized controlled trials (RCTs) and quasi-RCTs comparing deworming drugs for soil-transmitted helminths with placebo or no treatment in children aged 16 years or less, reporting on weight, haemoglobin, and formal tests of intellectual development. We also sought data on school attendance, school performance, and mortality. We included trials that combined health education with deworming programmes. DATA COLLECTION AND ANALYSIS At least two review authors independently assessed the trials, evaluated risk of bias, and extracted data. We analysed continuous data using the mean difference (MD) with 95% confidence intervals (CIs). Where data were missing, we contacted trial authors. We used outcomes at time of longest follow-up. The evidence quality was assessed using GRADE. This edition of the Cochrane Review adds the DEVTA trial from India, and draws on an independent analytical replication of a trial from Kenya. MAIN RESULTS We identified 45 trials, including nine cluster-RCTs, that met the inclusion criteria. One trial evaluating mortality included over one million children, and the remaining 44 trials included a total of 67,672 participants. Eight trials were in children known to be infected, and 37 trials were carried out in endemic areas, including areas of high (15 trials), moderate (12 trials), and low prevalence (10 trials). Treating children known to be infectedTreating children known to be infected with a single dose of deworming drugs (selected by screening, or living in areas where all children are infected) may increase weight gain over the next one to six months (627 participants, five trials, low quality evidence). The effect size varied across trials from an additional 0.2 kg gain to 1.3 kg. There is currently insufficient evidence to know whether treatment has additional effects on haemoglobin (247 participants, two trials, very low quality evidence); school attendance (0 trials); cognitive functioning (103 participants, two trials, very low quality evidence), or physical well-being (280 participants, three trials, very low quality evidence). Community deworming programmesTreating all children living in endemic areas with a dose of deworming drugs probably has little or no effect on average weight gain (MD 0.04 kg less, 95% CI 0.11 kg less to 0.04 kg more; trials 2719 participants, seven trials, moderate quality evidence), even in settings with high prevalence of infection (290 participants, two trials). A single dose also probably has no effect on average haemoglobin (MD 0.06 g/dL, 95% CI -0.05 lower to 0.17 higher; 1005 participants, three trials, moderate quality evidence), or average cognition (1361 participants, two trials, low quality evidence).Similiarly, regularly treating all children in endemic areas with deworming drugs, given every three to six months, may have little or no effect on average weight gain (MD 0.08 kg, 95% CI 0.11 kg less to 0.27 kg more; 38,392 participants, 10 trials, low quality evidence). The effects were variable across trials; one trial from a low prevalence setting carried out in 1995 found an increase in weight, but nine trials carried out since then found no effect, including five from moderate and high prevalence areas.There is also reasonable evidence that regular treatment probably has no effect on average height (MD 0.02 cm higher, 95% CI 0.14 lower to 0.17 cm higher; 7057 participants, seven trials, moderate quality evidence); average haemoglobin (MD 0.02 g/dL lower; 95% CI 0.08 g/dL lower to 0.04 g/dL higher; 3595 participants, seven trials, low quality evidence); formal tests of cognition (32,486 participants, five trials, moderate quality evidence); exam performance (32,659 participants, two trials, moderate quality evidence); or mortality (1,005,135 participants, three trials, low quality evidence). There is very limited evidence assessing an effect on school attendance and the findings are inconsistent, and at risk of bias (mean attendance 2% higher, 95% CI 4% lower to 8% higher; 20,243 participants, two trials, very low quality evidence).In a sensitivity analysis that only included trials with adequate allocation concealment, there was no evidence of any effect for the main outcomes. AUTHORS' CONCLUSIONS Treating children known to have worm infection may have some nutritional benefits for the individual. However, in mass treatment of all children in endemic areas, there is now substantial evidence that this does not improve average nutritional status, haemoglobin, cognition, school performance, or survival.
Collapse
Affiliation(s)
| | - Nicola Maayan
- CochraneCochrane ResponseSt Albans House57‐59 HaymarketLondonUKSW1Y 4QX
| | - Karla Soares‐Weiser
- CochraneCochrane Editorial UnitSt Albans House, 57 ‐ 59 HaymarketLondonUKSW1Y 4QX
| | - Sarah Donegan
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolUKL3 5QA
| | - Paul Garner
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolUKL3 5QA
| |
Collapse
|
17
|
Soil-Transmitted Helminths in Southwestern China: A Cross-Sectional Study of Links to Cognitive Ability, Nutrition, and School Performance among Children. PLoS Negl Trop Dis 2015; 9:e0003877. [PMID: 26110518 PMCID: PMC4481344 DOI: 10.1371/journal.pntd.0003877] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 06/05/2015] [Indexed: 11/29/2022] Open
Abstract
Background Empirical evidence suggests that the prevalence of soil-transmitted helminth (STH) infections in remote and poor rural areas is still high among children, the most vulnerable to infection. There is concern that STH infections may detrimentally affect children’s healthy development, including their cognitive ability, nutritional status, and school performance. Medical studies have not yet identified the exact nature of the impact STH infections have on children. The objective of this study is to examine the relationship between STH infections and developmental outcomes among a primary school-aged population in rural China. Methodology/Principal Findings We conducted a large-scale survey in Guizhou province in southwest China in May 2013. A total of 2,179 children aged 9-11 years living in seven nationally-designated poverty counties in rural China served as our study sample. Overall, 42 percent of the sample’s elementary school-aged children were infected with one or more of the three types of STH—Ascaris lumbricoides (ascaris), Trichuris trichuria (whipworm) and the hookworms Ancylostoma duodenale or Necator americanus. After controlling for socioeconomic status, we observed that infection with one or more STHs is associated with worse cognitive ability, worse nutritional status, and worse school performance than no infection. This study also presents evidence that children with Trichuris infection, either infection with Trichuris only or co-infected with Trichuris and Ascaris, experience worse cognitive, nutritional and schooling outcomes than their uninfected peers or children infected with only Ascaris. Conclusions/Significance We find that STH infection still poses a significant health challenge among children living in poor, rural, ethnic areas of southwest China. Given the important linkages we find between STH infection and a number of important child health and educational outcomes, we believe that our results will contribute positively to the debate surrounding the recent Cochrane report. Empirical evidence suggests that the prevalence of soil-transmitted helminth (STH) infections in remote and poor rural areas is still high among children, the most vulnerable to infection. There is concern that STH infections may detrimentally affect children’s healthy development, including their cognitive ability, nutritional status, and school performance. Medical studies have not yet identified the exact nature of the impact STH infections have on children. The objective of this study is to examine the relationship between STH infections and developmental outcomes among a primary school-aged population in rural China. We conducted a large-scale survey in Guizhou province in southwest China in May, 2013. Overall, 42 percent of elementary school-aged children were infected with one or more of the three types of STH—Ascaris lumbricoides (ascaris), Trichuris trichuria (whipworm) and the hookworms Ancylostoma duodenale or Necator americanus. After controlling for socioeconomic status, we observed that children infected with one or more STHs have worse cognitive ability, worse nutritional status, and worse school performance than their uninfected peers. While not causal, this study also presents evidence that children with Trichuris infection, either infection with Trichuris only or co-infected with Trichuris and Ascaris, have worse cognitive, nutritional and schooling outcomes than their uninfected peers or children infected with only Ascaris. Given these important linkages, we hope that our results will contribute positively to the debate surrounding the recent Cochrane report.
Collapse
|
18
|
Brückner S, Agnandji ST, Berberich S, Bache E, Fernandes JF, Schweiger B, Massinga Loembe M, Engleitner T, Lell B, Mordmüller B, Adegnika AA, Yazdanbakhsh M, Kremsner PG, Esen M. Effect of Antihelminthic Treatment on Vaccine Immunogenicity to a Seasonal Influenza Vaccine in Primary School Children in Gabon: A Randomized Placebo-Controlled Trial. PLoS Negl Trop Dis 2015; 9:e0003768. [PMID: 26053679 PMCID: PMC4459874 DOI: 10.1371/journal.pntd.0003768] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 04/17/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Helminth infections are a major public health problem, especially in the tropics. Infected individuals have an altered immune response with evidence that antibody response to vaccination is impaired. Hence, treatment of helminth infections before vaccination may be a simple intervention to improve vaccine immunogenicity. In the present study we investigated whether a single-dose antihelminthic treatment influences antibody responses to a seasonal influenza vaccine in primary school children living in Gabon, Central Africa. METHODS In this placebo-controlled double-blind trial conducted in Gabon the effect of a single-dose antihelminthic treatment with 400 mg albendazole versus a placebo one month prior to immunization with a seasonal influenza vaccine was investigated. Antiviral antibody titers against all three vaccine strains were assessed by haemagglutination inhibition (HI) test at baseline (Day 0; vaccination) and four weeks (Day 28) as well as 12 weeks (Day 84) following vaccination. Vaccine-specific memory B-cell response was measured at Day 0 and Day 84 by vaccine-specific Enzyme-linked Immunospot (ELISpot) assay. The trial is registered with the Pan African Clinical Trials Registry (PACTR) (PACTR201303000434188). RESULTS 98 school children aged 6-10 years were randomly allocated to receive either antihelminthic treatment or placebo and were vaccinated one month after the treatment. The prevalence of helminths at baseline was 21%. Vaccine-specific HI titers against at least one of the three vaccine strains increased at Day 28 and Day 84 in all participants. HI titers against both influenza A strains as well as memory B-cell response were modestly higher in the antihelminthic treated group compared to the placebo group but the difference was not statistically significant. Total but not specific IgA was elevated in the antihelminthic treated group compared to the control group at Day 28. CONCLUSION In our setting antihelminthic treatment had no significant effect on influenza vaccine immunogenicity. A trend towards better antiviral and vaccine immunogenicity in the antihelminthic treated group encourages studies to be conducted with alternative treatment schedules or in populations with a higher helminth burden.
Collapse
Affiliation(s)
- Sina Brückner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Selidji T. Agnandji
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Stefan Berberich
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Emmanuel Bache
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - José F. Fernandes
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Brunhilde Schweiger
- Nationales Referenzzentrum für Influenza, Robert-Koch-Institut, Berlin, Germany
| | | | - Thomas Engleitner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Bertrand Lell
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Benjamin Mordmüller
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Ayola A. Adegnika
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
- Leiden Medical University Center, Department of Parasitology, Leiden, The Netherlands
| | - Maria Yazdanbakhsh
- Leiden Medical University Center, Department of Parasitology, Leiden, The Netherlands
| | - Peter G. Kremsner
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Meral Esen
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Albert Schweitzer Hospital, Lambaréné, Gabon
| |
Collapse
|
19
|
Hotez PJ, Herricks JR. Helminth elimination in the pursuit of sustainable development goals: a "worm index" for human development. PLoS Negl Trop Dis 2015; 9:e0003618. [PMID: 25928617 PMCID: PMC4415765 DOI: 10.1371/journal.pntd.0003618] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Peter J. Hotez
- Department of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, Houston, Texas, United States of America
- James A. Baker III Institute for Public Policy, Rice University, Houston, Texas, United States of America
- Department of Biology, Baylor University, Waco, Texas, United States of America
- * E-mail:
| | - Jennifer R. Herricks
- Department of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- James A. Baker III Institute for Public Policy, Rice University, Houston, Texas, United States of America
| |
Collapse
|
20
|
Mireku MO, Boivin MJ, Davidson LL, Ouédraogo S, Koura GK, Alao MJ, Massougbodji A, Cot M, Bodeau-Livinec F. Impact of helminth infection during pregnancy on cognitive and motor functions of one-year-old children. PLoS Negl Trop Dis 2015; 9:e0003463. [PMID: 25756357 PMCID: PMC4355614 DOI: 10.1371/journal.pntd.0003463] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 12/08/2014] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVE To determine the effect of helminth infection during pregnancy on the cognitive and motor functions of one-year-old children. METHODS Six hundred and thirty five singletons born to pregnant women enrolled before 29 weeks of gestation in a trial comparing two intermittent preventive treatments for malaria were assessed for cognitive and motor functions using the Mullen Scales of Early Learning, in the TOVI study, at twelve months of age in the district of Allada in Benin. Stool samples of pregnant women were collected at recruitment, second antenatal care (ANC) visit (at least one month after recruitment) and just before delivery, and were tested for helminths using the Kato-Katz technique. All pregnant women were administered a total of 600 mg of mebendazole (100 mg two times daily for 3 days) to be taken after the first ANC visit. The intake was not directly observed. RESULTS Prevalence of helminth infection was 11.5%, 7.5% and 3.0% at first ANC visit, second ANC visit and at delivery, respectively. Children of mothers who were infected with hookworms at the first ANC visit had 4.9 (95% CI: 1.3-8.6) lower mean gross motor scores compared to those whose mothers were not infected with hookworms at the first ANC visit, in the adjusted model. Helminth infection at least once during pregnancy was associated with infant cognitive and gross motor functions after adjusting for maternal education, gravidity, child sex, family possessions, and quality of the home stimulation. CONCLUSION Helminth infection during pregnancy is associated with poor cognitive and gross motor outcomes in infants. Measures to prevent helminth infection during pregnancy should be reinforced.
Collapse
Affiliation(s)
- Michael O. Mireku
- Université Pierre et Marie Curie (UPMC- Paris VI), Paris, France
- Ecole des Hautes Etudes en Santé Publique, Département d’Épidémiologie et des Biostatistiques, Rennes, France
- Institut de Recherche pour le Développement (IRD), Mère et Enfant face aux Infections Tropicales, Paris, France
- * E-mail:
| | - Michael J. Boivin
- Michigan State University, Departments of Psychiatry and Neurology/Ophthalmology, East Lansing, Michigan, United States of America
| | - Leslie L. Davidson
- Columbia University, Mailman School of Public Health and the College of Physicians and Surgeons, New York, New York, United States of America
| | - Smaïla Ouédraogo
- Institut de Recherche pour le Développement (IRD), Mère et Enfant face aux Infections Tropicales, Paris, France
- Centre Hospitalier Universitaire Yalgado Ouédraogo, Ouagadougou, Burkina Faso
| | - Ghislain K. Koura
- Union Internationale Contre la Tuberculose et les Maladies Respiratoires, Département Tuberculose et VIH, Paris, France
| | - Maroufou J. Alao
- Hôpital de la Mère et de l’Enfant Lagune de Cotonou, Service de Pédiatrie, Cotonou, Bénin
| | | | - Michel Cot
- Institut de Recherche pour le Développement (IRD), Mère et Enfant face aux Infections Tropicales, Paris, France
- PRES Sorbonne Paris Cité, Université Paris Descartes, Faculté des Sciences Pharmaceutiques et Biologiques, Paris, France
| | - Florence Bodeau-Livinec
- Ecole des Hautes Etudes en Santé Publique, Département d’Épidémiologie et des Biostatistiques, Rennes, France
- Inserm UMR 1153, Obstetrical, Perinatal and Pediatric Epidemiology Research Team (Epopé), Center for Epidemiology and Statistics Sorbonne Paris Cité, DHU Risks in Pregnancy, Paris Descartes University, Paris, France
- New York University Medical Center, Division of Parasitology, Department of Microbiology, New York, New York, United States of America
| |
Collapse
|
21
|
Shelton JD. Response to “A False Dichotomy: RCTs and Their Contributions to Evidence-Based Public Health”. GLOBAL HEALTH: SCIENCE AND PRACTICE 2015; 3:141-3. [PMID: 25745129 PMCID: PMC4356284 DOI: 10.9745/ghsp-d-15-00045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
While randomized controlled trials (RCTs) can and do make valuable contributions, they also have severe limitations, including in answering the basic question of “Does it work?” and, even more so, in steering how to proceed with complex public health programming at scale. They deserve no exalted position in the pantheon of methodologies for evidence-based public health.
Collapse
|
22
|
Amza A, Yu SN, Kadri B, Nassirou B, Stoller NE, Zhou Z, West SK, Bailey RL, Gaynor BD, Keenan JD, Porco TC, Lietman TM. Does mass azithromycin distribution impact child growth and nutrition in Niger? A cluster-randomized trial. PLoS Negl Trop Dis 2014; 8:e3128. [PMID: 25210836 PMCID: PMC4161345 DOI: 10.1371/journal.pntd.0003128] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 07/20/2014] [Indexed: 11/27/2022] Open
Abstract
Background Antibiotic use on animals demonstrates improved growth regardless of whether or not there is clinical evidence of infectious disease. Antibiotics used for trachoma control may play an unintended benefit of improving child growth. Methodology In this sub-study of a larger randomized controlled trial, we assess anthropometry of pre-school children in a community-randomized trial of mass oral azithromycin distributions for trachoma in Niger. We measured height, weight, and mid-upper arm circumference (MUAC) in 12 communities randomized to receive annual mass azithromycin treatment of everyone versus 12 communities randomized to receive biannual mass azithromycin treatments for children, 3 years after the initial mass treatment. We collected measurements in 1,034 children aged 6–60 months of age. Principal Findings We found no difference in the prevalence of wasting among children in the 12 annually treated communities that received three mass azithromycin distributions compared to the 12 biannually treated communities that received six mass azithromycin distributions (odds ratio = 0.88, 95% confidence interval = 0.53 to 1.49). Conclusions/Significance We were unable to demonstrate a statistically significant difference in stunting, underweight, and low MUAC of pre-school children in communities randomized to annual mass azithromycin treatment or biannual mass azithromycin treatment. The role of antibiotics on child growth and nutrition remains unclear, but larger studies and longitudinal trials may help determine any association. Recent studies suggest that antibiotic use could have an effect on growth in humans. Azithromycin is an antibiotic used for trachoma control, and hence, may have an unintended benefit of improving child growth. Niger is a trachoma-endemic country where mass antibiotic distributions for trachoma take place and where malnutrition is widespread among children. In addition, azithromycin may have an effect on common childhood diseases associated with malnutrition, such as diarrhea, pneumonia, and malaria. In a community-randomized trachoma trial in Matameye, Niger, we assessed child growth by measuring height, weight, and mid-upper arm circumference of pre-school children who have received 3 years of annual or biannual mass azithromycin treatment. While these measures were better in the biannually treated communities, the difference was not statistically significant. Thus, further research will help determine the impact of antibiotics on child growth and nutrition.
Collapse
Affiliation(s)
- Abdou Amza
- Programme FSS/Université Abdou Moumouni de Niamey, Programme National de Santé Oculaire, Niamey, Niger
| | - Sun N. Yu
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
| | - Boubacar Kadri
- Programme FSS/Université Abdou Moumouni de Niamey, Programme National de Santé Oculaire, Niamey, Niger
| | - Baido Nassirou
- Programme FSS/Université Abdou Moumouni de Niamey, Programme National de Santé Oculaire, Niamey, Niger
| | - Nicole E. Stoller
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
| | - Zhaoxia Zhou
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
| | - Sheila K. West
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Robin L. Bailey
- Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Bruce D. Gaynor
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
| | - Jeremy D. Keenan
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
| | - Travis C. Porco
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Epidemiology & Biostatistics, University of California San Francisco, San Francisco, California, United States of America
- Institute for Global Health, University of California, San Francisco, California, United States of America
| | - Thomas M. Lietman
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
- Department of Epidemiology & Biostatistics, University of California San Francisco, San Francisco, California, United States of America
- Institute for Global Health, University of California, San Francisco, California, United States of America
- * E-mail:
| |
Collapse
|
23
|
Davis SM, Worrell CM, Wiegand RE, Odero KO, Suchdev PS, Ruth LJ, Lopez G, Cosmas L, Neatherlin J, Njenga SM, Montgomery JM, Fox LM. Soil-transmitted helminths in pre-school-aged and school-aged children in an urban slum: a cross-sectional study of prevalence, distribution, and associated exposures. Am J Trop Med Hyg 2014; 91:1002-10. [PMID: 25157123 DOI: 10.4269/ajtmh.14-0060] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Soil-transmitted helminths (STHs) are controlled by regular mass drug administration. Current practice targets school-age children (SAC) preferentially over pre-school age children (PSAC) and treats large areas as having uniform prevalence. We assessed infection prevalence in SAC and PSAC and spatial infection heterogeneity, using a cross-sectional study in two slum villages in Kibera, Nairobi. Nairobi has low reported STH prevalence. The SAC and PSAC were randomly selected from the International Emerging Infections Program's surveillance platform. Data included residence location and three stools tested by Kato-Katz for STHs. Prevalences among 692 analyzable children were any STH: PSAC 40.5%, SAC 40.7%; Ascaris: PSAC 24.1%, SAC 22.7%; Trichuris: PSAC 24.0%, SAC 28.8%; hookworm < 0.1%. The STH infection prevalence ranged from 22% to 71% between sub-village sectors. The PSAC have similar STH prevalences to SAC and should receive deworming. Small areas can contain heterogeneous prevalences; determinants of STH infection should be characterized and slums should be assessed separately in STH mapping.
Collapse
Affiliation(s)
- Stephanie M Davis
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Caitlin M Worrell
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Ryan E Wiegand
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Kennedy O Odero
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Parminder S Suchdev
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Laird J Ruth
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Gerard Lopez
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Leonard Cosmas
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - John Neatherlin
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Sammy M Njenga
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - Joel M Montgomery
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| | - LeAnne M Fox
- Parasitic Diseases Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Data Management Activity, Division of Parasitic Diseases and Malaria, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; International Emerging Infections Platform, Kenya Medical Research Institute-Centers for Disease Control and Prevention, Nairobi, Kenya; Nutrition Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Global Disease Detection, Centers for Disease Control and Prevention, Atlanta, Georgia; Eastern and Southern Africa Centre for International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya
| |
Collapse
|
24
|
Hürlimann E, Houngbedji CA, N'Dri PB, Bänninger D, Coulibaly JT, Yap P, Silué KD, N'Goran EK, Raso G, Utzinger J. Effect of deworming on school-aged children's physical fitness, cognition and clinical parameters in a malaria-helminth co-endemic area of Côte d'Ivoire. BMC Infect Dis 2014; 14:411. [PMID: 25060173 PMCID: PMC4131038 DOI: 10.1186/1471-2334-14-411] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 07/09/2014] [Indexed: 12/13/2022] Open
Abstract
Background Malaria and helminth infections are thought to negatively affect children’s nutritional status and to impair their physical and cognitive development. Yet, the current evidence-base is weak. The purpose of this study was to determine the effect of deworming against soil-transmitted helminthiasis and schistosomiasis on children’s physical fitness, cognition and clinical parameters in a malaria-helminth co-endemic setting of Côte d’Ivoire. Methods We designed an intervention study with a 5-month follow-up among schoolchildren aged 5–14 years from Niablé, eastern Côte d’Ivoire. In late 2012, a baseline cross-sectional survey was conducted. Finger-prick blood, stool and urine samples were subjected to standardised, quality-controlled techniques for the diagnosis of Plasmodium spp., Schistosoma spp., soil-transmitted helminths and intestinal protozoa infections. Haemoglobin level was determined and anthropometric measurements were taken for appraisal of anaemia and nutritional status. Children underwent memory (digit span) and attention (code transmission) cognitive testing, and their physical fitness and strength were determined (20 m shuttle run, standing broad jump and grip strength test). All children were treated with albendazole (against soil-transmitted helminthiasis) and praziquantel (against schistosomiasis) after the baseline cross-sectional survey and again 2 months later. Five months after the initial deworming, the same battery of clinical, cognitive and physical fitness tests was performed on the same children. Results Lower scores in strength tests were significantly associated with children with harbouring nutritional deficiencies. Surprisingly, boys infected with Schistosoma mansoni achieved longer jumping distances than their non-infected counterparts. Light-intensity infection with S. mansoni was associated with slightly better aerobic capacity. Deworming showed no effect on haemoglobin levels and anaemia, but children with moderate- to heavy-intensity Schistosoma infection at baseline gained weight more pronouncedly than non-infected children. Interestingly, children with soil-transmitted helminth or Schistosoma infection at baseline performed significantly better in the sustained attention test than their non-infected counterparts at the 5-month follow-up. Conclusions This study revealed conflicting results regarding clinical parameters and cognitive behaviour of children after two rounds of deworming. We speculate that potential beneficial effects of deworming are likely to be undermined in areas where malaria is co-endemic and nutritional deficiencies are widespread. Electronic supplementary material The online version of this article (doi:10.1186/1471-2334-14-411) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Giovanna Raso
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.
| | | |
Collapse
|
25
|
Effect of deworming on physical fitness of school-aged children in Yunnan, China: a double-blind, randomized, placebo-controlled trial. PLoS Negl Trop Dis 2014; 8:e2983. [PMID: 25010608 PMCID: PMC4091871 DOI: 10.1371/journal.pntd.0002983] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 05/14/2014] [Indexed: 11/19/2022] Open
Abstract
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, randomized, 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 standing 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. Children from the developing world are often burdened with intestinal worms due to poor water supply, sanitation, and hygiene. However, the assessment of the burden due to intestinal worms is difficult, and thus, the benefits of deworming are unclear. In this study, we determined the effect of deworming on the physical fitness and strength of 9- to 12-year-old children in Yunnan, China, where intestinal worms are common. Children were treated with triple-dose albendazole or placebo and monitored over a 6-month period. Stool samples were collected for the diagnosis of intestinal worm infections. Physical fitness was estimated with a 20-m shuttle run test and physical strength was assessed with grip strength and standing broad jump tests. Children receiving triple-dose albendazole scored slightly higher values in the primary and secondary outcomes than those children who were given placebo. However, the differences were not significant. We also found that children infected with intestinal worms performed significantly worse in the physical fitness and strength tests than their non-infected counterparts. In particular, the negative impact of whipworm infection on physical fitness warrants further investigation.
Collapse
|
26
|
The reliability of observational approaches for detecting interspecific parasite interactions: comparison with experimental results. Int J Parasitol 2014; 44:437-45. [DOI: 10.1016/j.ijpara.2014.03.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 02/27/2014] [Accepted: 03/02/2014] [Indexed: 11/22/2022]
|
27
|
Water, Sanitation, and Hygiene (WASH): a critical component for sustainable soil-transmitted helminth and schistosomiasis control. PLoS Negl Trop Dis 2014; 8:e2651. [PMID: 24722335 PMCID: PMC3983087 DOI: 10.1371/journal.pntd.0002651] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
28
|
School-based health education targeting intestinal worms-further support for integrated control. PLoS Negl Trop Dis 2014; 8:e2621. [PMID: 24626109 PMCID: PMC3953022 DOI: 10.1371/journal.pntd.0002621] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
29
|
Strunz EC, Addiss DG, Stocks ME, Ogden S, Utzinger J, Freeman MC. Water, sanitation, hygiene, and soil-transmitted helminth infection: a systematic review and meta-analysis. PLoS Med 2014; 11:e1001620. [PMID: 24667810 PMCID: PMC3965411 DOI: 10.1371/journal.pmed.1001620] [Citation(s) in RCA: 433] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 02/13/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Preventive chemotherapy represents a powerful but short-term control strategy for soil-transmitted helminthiasis. Since humans are often re-infected rapidly, long-term solutions require improvements in water, sanitation, and hygiene (WASH). The purpose of this study was to quantitatively summarize the relationship between WASH access or practices and soil-transmitted helminth (STH) infection. METHODS AND FINDINGS We conducted a systematic review and meta-analysis to examine the associations of improved WASH on infection with STH (Ascaris lumbricoides, Trichuris trichiura, hookworm [Ancylostoma duodenale and Necator americanus], and Strongyloides stercoralis). PubMed, Embase, Web of Science, and LILACS were searched from inception to October 28, 2013 with no language restrictions. Studies were eligible for inclusion if they provided an estimate for the effect of WASH access or practices on STH infection. We assessed the quality of published studies with the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. A total of 94 studies met our eligibility criteria; five were randomized controlled trials, whilst most others were cross-sectional studies. We used random-effects meta-analyses and analyzed only adjusted estimates to help account for heterogeneity and potential confounding respectively. Use of treated water was associated with lower odds of STH infection (odds ratio [OR] 0.46, 95% CI 0.36-0.60). Piped water access was associated with lower odds of A. lumbricoides (OR 0.40, 95% CI 0.39-0.41) and T. trichiura infection (OR 0.57, 95% CI 0.45-0.72), but not any STH infection (OR 0.93, 95% CI 0.28-3.11). Access to sanitation was associated with decreased likelihood of infection with any STH (OR 0.66, 95% CI 0.57-0.76), T. trichiura (OR 0.61, 95% CI 0.50-0.74), and A. lumbricoides (OR 0.62, 95% CI 0.44-0.88), but not with hookworm infection (OR 0.80, 95% CI 0.61-1.06). Wearing shoes was associated with reduced odds of hookworm infection (OR 0.29, 95% CI 0.18-0.47) and infection with any STH (OR 0.30, 95% CI 0.11-0.83). Handwashing, both before eating (OR 0.38, 95% CI 0.26-0.55) and after defecating (OR 0.45, 95% CI 0.35-0.58), was associated with lower odds of A. lumbricoides infection. Soap use or availability was significantly associated with lower infection with any STH (OR 0.53, 95% CI 0.29-0.98), as was handwashing after defecation (OR 0.47, 95% CI 0.24-0.90). Observational evidence constituted the majority of included literature, which limits any attempt to make causal inferences. Due to underlying heterogeneity across observational studies, the meta-analysis results reflect an average of many potentially distinct effects, not an average of one specific exposure-outcome relationship. CONCLUSIONS WASH access and practices are generally associated with reduced odds of STH infection. Pooled estimates from all meta-analyses, except for two, indicated at least a 33% reduction in odds of infection associated with individual WASH practices or access. Although most WASH interventions for STH have focused on sanitation, access to water and hygiene also appear to significantly reduce odds of infection. Overall quality of evidence was low due to the preponderance of observational studies, though recent randomized controlled trials have further underscored the benefit of handwashing interventions. Limited use of the Joint Monitoring Program's standardized water and sanitation definitions in the literature restricted efforts to generalize across studies. While further research is warranted to determine the magnitude of benefit from WASH interventions for STH control, these results call for multi-sectoral, integrated intervention packages that are tailored to social-ecological contexts.
Collapse
Affiliation(s)
- Eric C. Strunz
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - David G. Addiss
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - Meredith E. Stocks
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Stephanie Ogden
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
- International Trachoma Initiative, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Matthew C. Freeman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| |
Collapse
|
30
|
Zhan B, Beaumier CM, Briggs N, Jones KM, Keegan BP, Bottazzi ME, Hotez PJ. Advancing a multivalent 'Pan-anthelmintic' vaccine against soil-transmitted nematode infections. Expert Rev Vaccines 2014; 13:321-31. [PMID: 24392641 PMCID: PMC3934375 DOI: 10.1586/14760584.2014.872035] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ascaris lumbricoides The Sabin Vaccine Institute Product Development Partnership is developing a Pan-anthelmintic vaccine that simultaneously targets the major soil-transmitted nematode infections, in other words, ascariasis, trichuriasis and hookworm infection. The approach builds off the current bivalent Human Hookworm Vaccine now in clinical development and would ultimately add both a larval Ascaris lumbricoides antigen and an adult-stage Trichuris trichiura antigen from the parasite stichosome. Each selected antigen would partially reproduce the protective immunity afforded by UV-attenuated Ascaris eggs and Trichuris stichosome extracts, respectively. Final antigen selection will apply a ranking system that includes the evaluation of expression yields and solubility, feasibility of process development and the absence of circulating antigen-specific IgE among populations living in helminth-endemic regions. Here we describe a five year roadmap for the antigen discovery, feasibility and antigen selection, which will ultimately lead to the scale-up expression, process development, manufacture, good laboratory practices toxicology and preclinical evaluation, ultimately leading to Phase 1 clinical testing.
Collapse
Affiliation(s)
- Bin Zhan
- Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine , Houston, TX , USA
| | | | | | | | | | | | | |
Collapse
|
31
|
Affiliation(s)
- Eric S. Loker
- Center for Evolutionary and Theoretical Immunology, Parasitology Division – Museum of Southwestern Biology, Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131
| |
Collapse
|
32
|
Esser-von Bieren J, Mosconi I, Guiet R, Piersgilli A, Volpe B, Chen F, Gause WC, Seitz A, Verbeek JS, Harris NL. Antibodies trap tissue migrating helminth larvae and prevent tissue damage by driving IL-4Rα-independent alternative differentiation of macrophages. PLoS Pathog 2013; 9:e1003771. [PMID: 24244174 PMCID: PMC3828184 DOI: 10.1371/journal.ppat.1003771] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 10/02/2013] [Indexed: 12/18/2022] Open
Abstract
Approximately one-third of the world's population suffers from chronic helminth infections with no effective vaccines currently available. Antibodies and alternatively activated macrophages (AAM) form crucial components of protective immunity against challenge infections with intestinal helminths. However, the mechanisms by which antibodies target these large multi-cellular parasites remain obscure. Alternative activation of macrophages during helminth infection has been linked to signaling through the IL-4 receptor alpha chain (IL-4Rα), but the potential effects of antibodies on macrophage differentiation have not been explored. We demonstrate that helminth-specific antibodies induce the rapid trapping of tissue migrating helminth larvae and prevent tissue necrosis following challenge infection with the natural murine parasite Heligmosomoides polygyrus bakeri (Hp). Mice lacking antibodies (JH−/−) or activating Fc receptors (FcRγ−/−) harbored highly motile larvae, developed extensive tissue damage and accumulated less Arginase-1 expressing macrophages around the larvae. Moreover, Hp-specific antibodies induced FcRγ- and complement-dependent adherence of macrophages to larvae in vitro, resulting in complete larval immobilization. Antibodies together with helminth larvae reprogrammed macrophages to express wound-healing associated genes, including Arginase-1, and the Arginase-1 product L-ornithine directly impaired larval motility. Antibody-induced expression of Arginase-1 in vitro and in vivo occurred independently of IL-4Rα signaling. In summary, we present a novel IL-4Rα-independent mechanism of alternative macrophage activation that is antibody-dependent and which both mediates anti-helminth immunity and prevents tissue disruption caused by migrating larvae. Intestinal helminths present a pressing problem in developing countries with approximately 2 billion people suffering from chronic infection. To date no successful vaccines are available and a detailed mechanistic understanding of anti-helminth immunity is urgently needed to improve strategies for prevention and therapy. Antibodies form a crucial component of protective immunity against challenge infections with intestinal helminths. However, the exact mechanisms by which antibodies target these large multi-cellular parasites have remained obscure. We now demonstrate that helminth-specific antibodies induce the rapid trapping of tissue migrating helminth larvae by activating phagocytes. In the absence of antibodies or their receptors, helminth-infected mice developed extensive tissue damage, revealing a novel role for antibodies in limiting parasite-caused tissue disruption. Furthermore, helminth-specific antibodies reprogrammed macrophages to express wound-healing factors such as the arginine-metabolizing enzyme Arginase-1. Interestingly, the Arginase-1 product L-ornithine directly impaired the motility of helminth larvae. In summary, our study provides detailed mechanistic insights into how antibodies can modulate phagocyte function to provide protection against a large multi-cellular parasite. Our findings suggest that novel anti-helminth vaccines should target the larval surface and activate wound-healing macrophages to provide rapid protection against tissue-disruptive larvae.
Collapse
Affiliation(s)
- Julia Esser-von Bieren
- Swiss Vaccine Research Institute and Global Health Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Ilaria Mosconi
- Swiss Vaccine Research Institute and Global Health Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Romain Guiet
- Bioimaging and Optics Core Facility, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | | | - Beatrice Volpe
- Swiss Vaccine Research Institute and Global Health Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Fei Chen
- Center for Immunity and Inflammation, New Jersey Medical School, Newark, New Jersey, United States of America
| | - William C. Gause
- Center for Immunity and Inflammation, New Jersey Medical School, Newark, New Jersey, United States of America
| | - Arne Seitz
- Bioimaging and Optics Core Facility, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - J. Sjef Verbeek
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Nicola L. Harris
- Swiss Vaccine Research Institute and Global Health Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- * E-mail:
| |
Collapse
|
33
|
Yap P, Du ZW, Wu FW, Jiang JY, Chen R, Zhou XN, Hattendorf J, Utzinger J, Steinmann P. Rapid re-infection with soil-transmitted helminths after triple-dose albendazole treatment of school-aged children in Yunnan, People's Republic of China. Am J Trop Med Hyg 2013; 89:23-31. [PMID: 23690551 PMCID: PMC3748482 DOI: 10.4269/ajtmh.13-0009] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 03/27/2013] [Indexed: 01/01/2023] Open
Abstract
Post-treatment soil-transmitted helminth re-infection patterns were studied as part of a randomized controlled trial among school-aged children from an ethnic minority group in Yunnan province, People's Republic of China. Children with a soil-transmitted helminth infection (N = 194) were randomly assigned to triple-dose albendazole or placebo and their infection status monitored over a 6-month period using the Kato-Katz and Baermann techniques. Baseline prevalence of Trichuris trichiura, Ascaris lumbricoides, hookworm, and Strongyloides stercoralis were 94.5%, 93.3%, 61.3%, and 3.1%, respectively, with more than half of the participants harboring triple-species infections. For the intervention group (N = 99), the 1-month post-treatment cure rates were 96.7%, 91.5%, and 19.6% for hookworm, A. lumbricoides, and T. trichiura, respectively. Egg reduction rates were above 88% for all three species. Rapid re-infection with A. lumbricoides was observed: the prevalence 4 and 6 months post-treatment was 75.8% and 83.8%, respectively. Re-infection with hookworm and T. trichiura was considerably slower.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Peter Steinmann
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; Helminthiasis Division, Yunnan Institute of Parasitic Diseases, Pu'er, People's Republic of China; Menghai Center for Disease Control and Prevention, Menghai, People's Republic of China; National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People's Republic of China
| |
Collapse
|
34
|
Affiliation(s)
- Lucieni O Conterno
- Marilia Medical School; Department of General Internal Medicine and Clinical Epidemiology Unit; Avenida Monte Carmelo 800 Fragata Marilia São Paulo Brazil 17519-030
| | - Marcos VF Garcia
- Marilia Medical School; Rua Mussumes 312B Sao Paulo Brazil CEP: 01230-070
| | - Natalia S Mukai
- Marilia Medical School; Rua Mussumes 312B Sao Paulo Brazil CEP: 01230-070
| |
Collapse
|
35
|
Abstract
Childhood anemia has major adverse consequences for health and development. It's prevalence in India continues to range from 70 to 90%. Although anemia is multifactorial in etiology, preventative efforts have predominantly focused on increasing iron intake, primarily through supplementation in pregnant and lactating women. Policy thrust for childhood anemia is only recent. However, program implementation is dismal; only 3.8-4.7% of preschoolers receive iron-folate supplements. There is an urgent need for effective governance and implementation. Policy makers must distinguish anemia from iron deficiency, and introduce additional area-specific interventions as an integrated package.Increased iron intake may yield maximum benefit but will only address up to half the burden. In 6-59 months old children, instead of 100 days' continuous dosing with iron-folate syrup in a year, a directly supervised intermittent supplementation (biweekly; ~100 days per year) merits consideration. Multiple micronutrient powders for home fortification of foods in 6-23 months old infants do not appear viable. Additional interventions include delayed cord clamping, earlier supplementation in low birth weight infants, appropriate infant and young child feeding guidelines, and intermittent supervised supplementation in children and adolescents through school health programs. Use of double (iron-folate)-fortified salt in mid-day meal programs deserves piloting.Important area-specific, non-iron interventions include targeted deworming, and prevention and treatment of hemoglobinopathies, malaria and other common infections. Routine addition of multi-micronutrients to iron-folate supplementation appears unjustified currently. There is a pressing need to conduct relevant research, especially to inform etiology, additional interventions and implementation issues.
Collapse
|