Environmental Enteropathy Research Articles

Markers of Environmental Enteric Dysfunction Are Associated with Poor Growth and Iron Status in Rural Ugandan Infants

ABSTRACTBackgroundEnvironmental enteric dysfunction (EED), characterized by altered intestinal permeability/inflammation, microbial translocation, and systemic inflammation (SI), may be a significant contributor to micronutrient deficiencies and poor growth in infants from low-resource settings.ObjectiveWe examined associations among EED, SI, growth, and iron status at 6 mo of age.MethodsWe performed a cross-sectional analysis of 6-mo-old infants (n = 548) enrolled in a Ugandan birth-cohort study (NCT04233944). EED was assessed via serum concentrations of anti-flagellin and anti- LPS immunoglobulins (Igs); SI was assessed via serum concentrations of ɑ1-acid glycoprotein (AGP) and C-reactive protein (CRP); iron status was assessed via serum concentrations of hemoglobin (Hb), soluble transferrin receptor (sTfR), and ferritin. Associations were assessed using adjusted linear regression analysis.ResultsAt 6 mo, ∼35% of infants were stunted [length-for-age z score (LAZ) < −2] and ∼53% were anemic [hemoglobin (Hb) <11.0 g/dL]. Nearly half (∼46%) had elevated AGP (>1 g/L) and ∼30% had elevated CRP (>5 mg/L). EED and SI biomarkers were significantly correlated (r = 0.142–0.193, P < 0.001 for all). In adjusted linear regression models, which included adjustments for SI, higher anti-flagellin IgA, anti-LPS IgA, and anti-LPS IgG concentrations were each significantly associated with lower LAZ [β (95% CI): −0.21 (−0.41, 0.00), −0.23 (−0.44, −0.03), and −0.33 (−0.58, −0.09)]. Furthermore, higher anti-flagellin IgA, anti-flagellin IgG, and anti-LPS IgA concentrations were significantly associated with lower Hb [β (95% CI): −0.24 (−0.45, −0.02), −0.58 (−1.13, 0.00), and −0.26 (−0.51, 0.00)] and higher anti-flagellin IgG and anti-LPS IgG concentrations were significantly associated with higher sTfR [β (95% CI): 2.31 (0.34, 4.28) and 3.13 (0.75, 5.51)].ConclusionsEED is associated with both low LAZ and iron status in 6-mo-old infants. Further research on the mechanisms by which EED affects growth and micronutrient status is warranted.

A scientometric analysis of birth cohorts in South Asia: Way forward for Pakistan.

The present study aims to: a) systematically map the of birth cohort studies from the South Asian region b) examine the major research foci and landmark contributions from these cohorts using reproducible scientometric techniques and c) offer recommendations on establishing new birth cohorts in Pakistan, building upon the strengths, weaknesses and gaps of previous cohorts. Bibliographic records for a total of 260 articles, published during through December 2018, were retrieved from the Web of Science (core database). All data were analysed using Microsoft Excel (2013), Web of Science platform and CiteSpace. A series of network analysis were then run for each time-period using the link reduction method and pathfinder network scaling. The co-cited articles were clustered into their homogeneous research clusters. The clusters were named using the Latent Semantic Indexing (LSI) method that utilized author keywords as source of names for these clusters. The scientometric analyses of original research output from these birth cohorts also paint a pessimistic landscape in Pakistan- where Pakistani sites for birth cohorts contributed only 31 publications; a majority of these utilized the MAL-ED birth cohort data. A majority of original studies were published from birth cohorts in India (156), Bangladesh (63), and Nepal (15). Out of these contributions, 31 studies reported data from multiple countries. The three major birth cohorts include prospective and multi-country MAL-ED birth cohort and The Pakistan Early Childhood Development Scale Up Trial, and a retrospective Maternal and infant nutrition intervention cohort. In addition to these, a few small-scale birth cohorts reported findings pertaining to neonatal sepsis, intrauterine growth retardation and its effects on linear growth of children and environmental enteropathy.

Intervention and Mechanisms of Alanyl-glutamine for Inflammation, Nutrition, and Enteropathy: A Randomized Controlled Trial.

Objective:Determine the minimum dosage of alanyl-glutamine (Ala-Gln) required to improve gut integrity and growth in children at risk of environmental enteropathy (EE).Methods:This was a double-blinded randomized placebo-controlled dose-response trial. We enrolled 140 children residing in a low-income community in Fortaleza, Brazil. Participants were 2 to 60 months old and had weight-for-age (WAZ), height-for-age (HAZ), or weight-for-height (WHZ) z-scores less than −1. We randomized children to 10 days of nutritional supplementation: Ala-Gln at 3 g/day, Ala-Gln at 6 g/day, Ala-Gln at 12 g/day, or an isonitrogenous dose of glycine (Gly) placebo at 12.5 g/day. Our primary outcome was urinary lactulose-mannitol excretion testing. Secondary outcomes were anthropometry, fecal markers of inflammation, urine metabolic profiles, and malabsorption (spot fecal energy).Results:Of 140 children, 103 completed 120 days of follow-up (24% dropout). In the group receiving the highest dose of Ala-Gln, we detected a modest improvement in urinary lactulose excretion from 0.19% on day 1 to 0.17% on day 10 (P=0.05). We observed significant but transient improvements in WHZ at day 10 in 2 Ala-Gln groups, and in WHZ and WAZ in all Ala-Gln groups at day 30. We detected no effects on fecal inflammatory markers, diarrheal morbidity, or urine metabolic profiles; but did observe modest reductions in fecal energy and fecal lactoferrin in participants receiving Ala-Gln.Conclusions:Intermediate dose Ala-Gln promotes short-term improvement in gut integrity and ponderal growth in children at risk of EE. Lower doses produced improvements in ponderal growth in the absence of enhanced gut integrity.

Impact of Different Strategies for Delivering Supplemental Zinc on Selected Fecal Markers of Environmental Enteric Dysfunction among Young Laotian Children: A Randomized Controlled Trial.

.The objective of this study was to assess the impact of different strategies for delivering supplemental zinc on fecal myeloperoxidase (MPO), neopterin (NEO), and calprotectin (CAL) among young Laotian children. In a double-blind controlled trial, children aged 6–23 months were randomized to receive either daily preventive zinc (PZ) tablets (7 mg/day), daily micronutrient powder (MNP; containing 10 mg zinc and 14 other micronutrients), therapeutic zinc (TZ) supplements for diarrhea treatment (20 mg/day for 10 days), or daily placebo powder and followed for ∼36 weeks. Stool samples were collected at baseline and endline. Fecal MPO, NEO, and CAL concentrations were determined in a randomly selected subsample of 720 children using commercially available ELISA kits. At baseline, the mean age was 14.1 ± 4.9 months and prevalence of stunting was 39%. The endline prevalence of stunting was 43%; there was no overall treatment effect on physical growth in the parent trial. At endline, the mean (95% CI) MPO in the PZ group was 1,590 [1,396; 1,811] ng/mL and did not differ from that in the MNP (1,633 [1,434; 1,859] ng/mL), TZ (1,749 [1,535; 1,992] ng/mL), and control (1,612 [1,415; 1,836] ng/mL) groups (P = 0.749). Similarly, there was no overall treatment effect on NEO and CAL concentrations (P = 0.226 and 0.229, respectively). In this population, the provision of PZ or TZ supplements or MNP had no impact on growth or environmental enteric dysfunction (EED) as assessed by fecal MPO, NEO, and CAL. Additional research is needed to better understand the etiology and proposed mechanisms of EED pathogenesis.

Growth velocity in children with Environmental Enteric Dysfunction is associated with specific bacterial and viral taxa of the gastrointestinal tract in Malawian children.

Environmental enteric dysfunction (EED) is characterized by diffuse villous atrophy of the small bowel. EED is strongly associated with stunting, a major public health problem linked to increased childhood morbidity and mortality. EED and subsequent stunting of linear growth are surmised to have microbial origins. To interrogate this relationship, we defined the comprehensive virome (eukaryotic virus and bacteriophage) and bacterial microbiome of a longitudinal cohort of rural Malawian children with extensive metadata and intestinal permeability testing at each time point. We found thirty bacterial taxa differentially associated with linear growth. We detected many eukaryotic viruses. Neither the total number of eukaryotic families nor a specific viral family was statistically associated with improved linear growth. We identified 3 differentially abundant bacteriophage among growth velocities. Interestingly, there was a positive correlation between bacteria and bacteriophage richness in children with subsequent adequate/moderate growth which children with subsequent poor growth lacked. This suggests that a disruption in the equilibrium between bacteria and bacteriophage communities might be associated with subsequent poor growth. Future studies of EED and stunting should include the evaluation of viral communities in addition to bacterial microbiota to understand the complete microbial ecology of these poorly understood entities.

HMIC: Hierarchical Medical Image Classification, A Deep Learning Approach.

Image classification is central to the big data revolution in medicine. Improved information processing methods for diagnosis and classification of digital medical images have shown to be successful via deep learning approaches. As this field is explored, there are limitations to the performance of traditional supervised classifiers. This paper outlines an approach that is different from the current medical image classification tasks that view the issue as multi-class classification. We performed a hierarchical classification using our Hierarchical Medical Image classification (HMIC) approach. HMIC uses stacks of deep learning models to give particular comprehension at each level of the clinical picture hierarchy. For testing our performance, we use biopsy of the small bowel images that contain three categories in the parent level (Celiac Disease, Environmental Enteropathy, and histologically normal controls). For the child level, Celiac Disease Severity is classified into 4 classes (I, IIIa, IIIb, and IIIC).

Impact of Protein Supplementation and Presumptive Treatment for Enteric Pathogens on Infant Growth from 6–12 Months of Age: Results of a Cluster-Randomized Controlled Trial

Abstract Objectives Intake of high-quality protein may be insufficient to support growth in the context of high enteric pathogen carriage and environmental enteric dysfunction. Our objective was to test whether supplemental protein, with or without presumptive treatment for enteric pathogens, would improve infant growth from 6–12 months of age. Methods We conducted a 2 × 4 factorial cluster-randomized trial in rural Bangladesh. The first factor was azithromycin treatment (10 mg/kg * 3 days) or placebo at 6 &amp; 9 months of age. The second factor, delivered from 6–12 months of age, consisted of: supplemental protein as daily porridge (125 kcal/d, with 10 g protein/day as egg white powder) or a daily egg; an isocaloric daily porridge; or nutrition education alone. The present aim tested the impact of the protein-rich porridge, with or without azithromycin treatment. All infants born in the study area over a 9-mo period were eligible and consented at ∼3 mo of age. Trained field workers measured infant size at 6, 9, and 12 mo of age using standardized protocols. We used linear regression with generalized estimating equations to test the interventions’ impact on anthropometric indices, respectively, at 12 mo of age, controlling for baseline measures. Analysis was intention-to-treat. Results Overall, 2205 infants were enrolled from 282 clusters and exposed to both nutrition (1074 in protein arm from 140 clusters; 1074 in the isocaloric arm from 142 clusters) and presumptive treatment interventions. At baseline, 18.7%, 16.9%, and 6.4% of infants were stunted, underweight, and wasted, respectively. There was no statistical interaction between protein supplementation and azithromycin treatment for any of the anthropometric indices, so groups were combined. In the analysis of main effects, added protein had no impact on mean length-for-age (β = 0.01; 95% CI: −0.06, 0.08), weight-for-age (β = −0.002; 95% CI: −0.06, 0.05), or weight-for-length (β = −0.04; 95% CI: −0.12, 0.05) Z-scores at 12 mo of age. Conclusions Supplemental protein from 6–12 mo of age had no effect on mean linear or ponderal growth measured at 12 mo of age, irrespective of presumptive treatment for enteric pathogens with azithromycin. Funding Sources The Bill and Melinda Gates Foundation.

Markers of Environmental Enteric Dysfunction Are Associated with Poor Growth and Iron Status in Rural Ugandan infants

Abstract Objectives Environmental enteric dysfunction (EED), characterized by altered intestinal permeability/inflammation, microbial translocation, and systemic inflammation (SI), may be a significant contributor to poor growth and micronutrient deficiencies in infants from low-resource setting. The objective of this study was to examine relationships among EED, SI, growth, and iron status in a sample of 6-months old infants from rural Uganda. Methods We performed a cross-sectional analysis using a subset of infants (n = 548) enrolled in a birth cohort study conducted in 16 sub-counties across northern and southwestern Uganda. EED was assessed via serum levels of antibodies to the bacterial components flagellin and lipopolysaccharide (LPS); SI was assessed via serum levels of alpha(1)-acid glycoprotein (AGP) and C-reactive protein (CRP); iron status was assessed via serum levels of hemoglobin (Hb), soluble transferrin receptor (sTfR), and ferritin. Associations were assessed using adjusted linear regression analysis. Results At 6 months, ∼35% of infants were stunted (LAZ &amp;lt; −2), and ∼53% were anemic (Hb &amp;lt; 11.0 g/dL). Nearly half (∼46%) had elevated AGP (&amp;gt;1 g/L) and ∼30% had elevated CRP (&amp;gt;5 mg/L). EED biomarkers were significantly correlated with SI biomarkers (r = 0.142–0.193, P &amp;lt; 0.001 for all). In adjusted linear regression models, which included adjustments for SI, higher anti-flagellin IgA, anti-LPS IgA, and anti-LPS IgG levels were significantly associated with lower LAZ [β: −0.21 (95% CI: −0.41, 0.00), β: −0.23 (95% CI: −0.44, −0.03), and β: −0.33 (95% CI: −0.58, −0.09)]. Furthermore, higher anti-flagellin IgA, anti-flagellin IgG, and anti-LPS IgA levels were significantly associated with lower Hb levels [β: −0.24 (95% CI: −0.45, −0.02), β: −0.58 (95% CI: −1.13, 0.00), and β: −0.26 (95% CI: −0.51, 0.00)]; higher anti-flagellin IgG and anti-LPS IgG levels were significantly associated with higher sTfR levels [β: 2.31 (95% CI: 0.34, 4.28) and β: 3.13 (95% CI: 0.75, 5.51)]. Conclusions Independent of SI, EED is associated with both low LAZ and iron status in 6-months old infants. Further research on the mechanisms by which EED affects growth and micronutrient status is warranted. Funding Sources USAID, award AID-OAA-L-10–00006 to the Friedman School of Nutrition Science and Policy at Tufts University. CD was supported in part by NIH grants K24DK104676 and 2P30 DK040561.

A Retrospective Case-Control Study of the Relationship between the Gut Microbiota, Enteropathy, and Child Growth.

The microbial communities residing in the child gut are thought to play an important role in child growth, although the relationship is not well understood. We examined a cohort of young children from Mirzapur, Bangladesh, prospectively over 18 months. Four fecal markers of environmental enteropathy (EE) (high levels of alpha-1-antitrypsin, calprotectin, myeloperoxidase, and neopterin) were examined and anthropometric measures obtained from a cohort of 68 children. The 16S rRNA gene of bacterial DNA was sequenced from stool samples and used to estimate amplicon sequence variants (ASVs). We age-matched children with poor growth to children with normal growth within 1 month and compared the change in abundance and diversity of ASVs over time. Elevated EE markers and poor linear growth in children were associated with changes in microbial communities in the gut. There were increased amounts of Escherichia/Shigella and Proteobacteria and decreased amounts of Prevotella associated with poorly growing children consistent with the mounting evidence supporting the relationship between intestinal inflammation, child growth, and changes in gut microbiota composition. Future research is needed to investigate this association among young children in low- and middle-income countries.

Child Salivary SIgA and Its Relationship to Enteric Infections and EED Biomarkers in Maputo, Mozambique.

Characterizing child immunological responses to enteric infections with antibody detection in serum can be challenging in resource-constrained field settings, because sample collection requires trained individuals and its invasive procedure may lead to low response rates, especially among children. Saliva may present a promising non-invasive alternative. The objectives of this research were to compare salivary antibody levels in children to enteric infections and biomarkers of environmental enteric dysfunction (EED). We collected saliva samples from children aged one to six years enrolled in a sanitation trial in Maputo, Mozambique, and characterized salivary secretory immunoglobulin A (SIgA) concentrations with enzyme-linked immunosorbent assays. We used multilevel linear models to analyze cross-sectional associations between salivary SIgA and the number of concurrent enteric pathogen infections, as well as EED biomarkers in matched stool samples. Median salivary SIgA concentrations in this study population were 54 μg/mL (inter-quartile range (IQR): 34, 85 μg/mL), and SIgA levels were similar between children of different ages. SIgA was lower in children experiencing a higher number of concurrent infections −0.04 log μg/mL (95% confidence interval (CI): −0.08 to −0.005 log μg/mL), but was not associated with any of the included EED biomarkers. Contrary to evidence from high-income countries that suggests salivary SIgA increases rapidly with age in young children, the high prevalence of enteric infections may have led to a suppression of immunological development in this study sample and could in part explain the similar SIgA levels between children of different ages.

Helicobacter pylori infection is associated with fecal biomarkers of environmental enteric dysfunction but not with the nutritional status of children living in Bangladesh.

Because Helicobacter pylori (H. pylori) infection and Environmental Enteric Dysfunction (EED) follow a similar mode of transmission, there can be a complex interplay between H. pylori infection and EED, both of which can influence childhood growth. We sought to investigate the factors associated with H. pylori infection and identify its relationship with the fecal biomarkers of EED including Myeloperoxidase (MPO), Neopterin (NEO), Calprotectin, Reg1B and Alpha-1 antitrypsin (AAT), and nutritional status of the children. Data from an on-going community-based nutrition intervention study was used for this analysis. Total 319 children aged between 12-18 months were evaluated at enrolment and at the end of a 90-day nutrition intervention. Multivariable linear regression with generalized estimating equations was done to examine the association of H. pylori infection with stool biomarker of EED and nutritional status of the children. One-fifth of the participants had H. pylori infection at both the time points, with 13.8% overall persistence. Children living in crowded households had higher odds of being infected by H. pylori (AOR = 2.02; 95% CI = 1.02, 4.10; p-value = 0.045). At enrolment, 60%, 99%, 69% and 85% of the stool samples were elevated compared to the reference values set for MPO, NEO, AAT and Calprotectin in the non-tropical western countries. The proportions reduced to 52%, 99%, 67%, and 77% for the same biomarkers after the nutrition intervention. Infection with H. pylori had significant positive association with fecal AAT concentrations (Coefficient = 0.26; 95% CI = 0.02, 0.49; p-value = 0.03) and inverse relationship with Reg1B concentrations measured in the stool samples (Coefficient = -0.32; 95% CI = -0.59, -0.05; p-value = 0.02). However, H. pylori infection was not associated with the indicators of childhood growth. The study findings affirmed that the acquisition and persistence of H. pylori infection in the early years of life may exert an adverse impact on intestinal health, induce gut inflammation and result in increased intestinal permeability.

Co-occurrence of Campylobacter Species in Children From Eastern Ethiopia, and Their Association With Environmental Enteric Dysfunction, Diarrhea, and Host Microbiome.

High Campylobacter prevalence during early childhood has been associated with stunting and environmental enteric dysfunction (EED), especially in low resource settings. This study assessed the prevalence, diversity, abundance, and co-occurrence of Campylobacter spp. in stools from children in a rural area of eastern Ethiopia and their association with microbiome, diarrhea, and EED in children. Stool samples (n = 100) were collected from randomly selected children (age range: 360–498 days) in five kebeles in Haramaya District, Ethiopia. Diarrhea, compromised gut permeability, and gut inflammation were observed in 48, 45, and 57% of children, respectively. Campylobacter prevalence and species diversity were assessed using PCR and meta-total RNA sequencing (MeTRS). The prevalence of Campylobacter spp. in the children's stools was 50% (41–60%) by PCR and 88% (80–93.6%) by MeTRS (P < 0.01). Further, seven Campylobacter species (Campylobacter jejuni, Campylobacter upsaliensis, Campylobacter hyointestinalis, Campylobacter coli, Campylobacter sp. RM6137, uncultured Campylobacter sp., and Campylobacter sp. RM12175) were detected by MeTRS in at least 40% of children stools in high abundance (>1.76-log read per million per positive stool sample). Four clusters of Campylobacter species (5–12 species per cluster) co-occurred in the stool samples, suggesting that Campylobacter colonization of children may have occurred through multiple reservoirs or from a reservoir in which several Campylobacter species may co-inhabit. No associations between Campylobacter spp., EED, and diarrhea were detected in this cross-sectional study; however, characteristic microbiome profiles were identified based on the prevalence of Campylobacter spp., EED severity, and diarrhea. Forty-seven bacterial species were correlated with Campylobacter, and 13 of them also correlated with gut permeability, gut inflammation and/or EED severity. Forty-nine species not correlated with Campylobacter were correlated with gut permeability, gut inflammation, EED severity and/or diarrhea. This study demonstrated that (1) in addition to C. jejuni and C. coli, multiple non-thermophilic Campylobacter spp. (i.e., Campylobacter hyointestinalis, Campylobacter fetus, and Campylobacter concisus) were frequently detected in the children's stools and (2) the Campylobacter, gut permeability, gut inflammation, EED severity, and diarrhea were associated with characteristic microbiome composition. Additional spatial and longitudinal studies are needed to identify environmental reservoirs and sources of infection of children with disparate Campylobacter species and to better define their associations with EED in low-income countries.

Human Colonoids as a Model for Studying Host‐Pathogen Interactions with Campylobacter jejuni

BackgroundCampylobacter is a leading cause of bacterial enterocolitis in the U.S. and around the world. In addition to the acute morbidity, it is associated with delayed sequelae such as environmental enteropathy and post‐infection irritable bowel syndrome. Host responses to Campylobacter infection are poorly studied due to colonization resistance in mice thereby restricting virulence studies to immortalized cell lines. These models lack the complexity of the host environment. Recent studies have highlighted the use of organoids for studying enteric pathogens. We propose that human organoids provide a unique platform for studying pathogenic mechanisms incorporating unique host (human) and infection (strain) characteristics.ObjectiveTo demonstrate human colonic organoids (colonoids) as a model for studying C. jejuni infection.MethodsSigmoid colonic biopsies were collected from healthy volunteers between 18–35 years of age (n=3). Intestinal crypts were isolated, washed and plated in matrigel domes for colonoid formation. Mature colonoids were harvested after 7 days, and dissociated using a 0.05% trypsin solution. These were plated on collagen IV coated plates, generating 2D‐monolayers for infection experiments. Three different C. jejuni strains (Sequence Types 45, 22, 8) were grown to an OD600 of 1 and used to infect the colonoid monolayers. To assess adhesion and internalization, colonoids were infected for a total of 3 hours after which monolayers were either washed and subsequently lysed (to determine attached plus invaded bacteria) or treated with gentamycin and then lysed (to determine invaded bacteria). Bacterial quantification was done by plating on Mueller Hinton agar. Additional colonoid monolayers were grown on permeable transwell inserts. Baseline transepithelial resistance (TER) of confluent monolayers was recorded and then continuously assessed every hour after the addition of the C. jejuni strains (using impedance spectroscopy in cellZscope) to evaluate changes in barrier integrity.ResultsAll C. jejuni strains attached and invaded colonoid monolayers derived from all three volunteers. Two strains (ST 45 and 22) caused greater adhesion and invasion in all three colonoids compared to the third strain (Adhesion mean (SEM): 4.32 x 10−2 (2.33 x 10−3), 9.36 x 10−3 (4.82 x 10−4) vs 7.79 x 10−3 (3.51 x 10−3); Invasion mean (SEM) 3.47 x 10−4 (2.13 x 10−5), 2.33 x 10−4 (1.36 x 10−4) vs 4.57 x 10−5 (1.73 x 10−5) (ANOVA, p&lt;0.05, n=3/group for both analyses). Additionally, greater drop in TER was seen in colonoid monolayers exposed to the two strains with higher adhesion and invasion (Mean % of baseline TER at 30 hr post‐infection 2.58% (1.21), 14.14% (3.39) vs 42.29% (18.49), p&lt;0.01). These results correlated with virulence of these strains in conventional T84 monolayers. Transcriptomic and proteomic characterization of the C. jejuni infection in these colonoids is in progress.ConclusionsHuman colonoids are useful to assess the role of the host in infectivity and epithelial barrier responses to C. jejuni infection. Future work involves determining responses in colonoids derived from volunteers with specific characteristics to create unique host‐bacterial infection models.Support or Funding InformationSupported by funding from Department of Defense W81XWH‐18‐1‐0074

The ICAReB Platform: A Human Biobank for the Institut Pasteur and Beyond

The ICAReB platform of Institut Pasteur provides access to human bio-resources for academic and private research teams worldwide, essentially in the fields of infection, immunity and neurosciences. More than 134,000 human quality controlled, duly annotated samples (mainly whole-blood derived products, but also stool, urine, saliva, swabs….), from both healthy and diseased cohorts with open, regulated access, are available upon request. Both clinical investigation and biobanking activities are certified following ISO 9001:2015 and NF S96-900:2011 standards, respectively. ICAReB is a member of PIBnet (Pasteur International Biobanking network), BIOBANQUES and BBMRI, the French and pan-european biobanking networks, respectively. Funding statement: Funds come from IP (facilities and staff), and from various funding organisms or agencies (for specific projects): ANR (French National Research funding Agency): OH!Ticks project (see https://www.ohticks.fr/ 2017–2020) AP/HP (Assistance Publique/Hopitaux de Paris): MonaLisa (Multicentric Observational National Analysis on Listeriosis and Listeria) and ListeriaGEN projects, 2009–2022 and 2015–2024, respectively AVIESAN (French National alliance for Life Sciences and Health). Study of the innate immunity and the microbial flora during aplasia (PAMPA project, 2013–2016) Bioaster (French Investissements d’Avenir funding, Infectiology and Microbiology platform, Lyon-Paris, 2010–2020) Biomerieux (Lyon, France; cardio-vascular biomarker, 2013–2015) FRM (Medical Research Foundation): Hidradenitis Suppurativa project (2011–2015) IBiSA (Biology, Health and Agronomics infrastructure) selection of ICAReB platform in 2009 INCA (National Institute for Cancer research): INECOC project, 2009–2011 TOTAL foundation (Afribiota project on Environmental Pediatric Enteropathy, 2016-2020) WHO (for The WHO Human African Trypanosomiasis specimen Bank, 2008–2018, 2019–). Since three years, public-private relationships were proposed and research collaborations accepted with industrial partners, for example the Lyon-Paris ‘Technological Research Institute’ (BioAster) following a national Investissements d’Avenir program launched in 2012.

Chicken eggs, childhood stunting and environmental hygiene: an ethnographic study from the Campylobacter genomics and environmental enteric dysfunction (CAGED) project in Ethiopia

BackgroundChildhood stunting and malnutrition condemn millions of people globally to a life of disadvantage and cognitive and physical impairment. Though increasing egg consumption is often seen as an important solution for low and middle income countries (including Ethiopia), emerging evidence suggests that greater exposure to poultry feces may also inhibit child growth due to the effects of enteric bacteria, especially Campylobacter, on gut health.MethodsIn this rapid ethnographic study, we explored village poultry production, child dietary practices, and environmental hygiene conditions as they relate to Campylobacter risk and intervention in 16 villages in Haramaya Woreda, Eastern Ethiopia.ResultsIn the study area, we found that women assumed primary responsibility to care for both chickens and children: in feeding, housing, and healthcare. Most chickens were free-range local indigenous breeds, and flock sizes were small and unstable due to epidemics, seasonal trends, reproductive patterns, and lack of food. Generally, eggs were seen as “too luxurious” to be eaten, and were predominantly sold at local markets for scarce cash, despite high malnutrition rates. Local narratives of extreme poverty, social dietary norms, parental fatalism, and lack of “dietary consciousness” (as it was called) were invoked to explain this. We found that homesteads were highly contaminated with human and animal feces. Although community members viewed chicken feces and poultry gastrointestinal contents as particularly noxious in comparison to other animals because of their feeding behaviour, they did not relate them to any particular disease. Shared human-animal housing and childcare practices place children at high risk of exposure to enteric bacteria from animal manure, despite daily routines designed to manage the domestic landscape.ConclusionsAddressing childhood stunting and malnutrition through egg production in rural landscapes like Haramaya must navigate three distinct health and care regimes: for children, chickens, and home environments. Interventions should be based on a holistic approach to social and economic empowerment, one that considers both women and men and integrates nutrition, health, and community change as its overarching goal.

Immune predictors of oral poliovirus vaccine immunogenicity among infants in South India

Identification of the causes of poor oral vaccine immunogenicity in low-income countries might lead to more effective vaccines. We measured mucosal and systemic immune parameters at the time of vaccination with oral poliovirus vaccine (OPV) in 292 Indian infants aged 6–11 months, including plasma cytokines, leukocyte counts, fecal biomarkers of environmental enteropathy and peripheral blood T-cell phenotype, focused on gut-homing regulatory CD4+ populations. We did not find a distinct immune phenotype associated with OPV immunogenicity, although viral pathogens were more prevalent in stool at the time of immunization among infants who failed to seroconvert (63.9% vs. 45.6%, p = 0.002). Using a machine-learning approach, we could predict seroconversion a priori using immune parameters and infection status with a median 58% accuracy (cross-validation IQR: 50–69%) compared with 50% expected by chance. Better identification of immune predictors of OPV immunogenicity is likely to require sampling of mucosal tissue and improved oral poliovirus infection models.

Effects of improved water, sanitation, and hygiene and improved complementary feeding on environmental enteric dysfunction in children in rural Zimbabwe: Acluster-randomized controlled trial.

BackgroundEnvironmental enteric dysfunction (EED) may be an important modifiable cause of child stunting. We described the evolution of EED biomarkers from birth to 18 months in rural Zimbabwe and tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF), on EED.Methodology and findingsThe Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial was a 2x2 factorial cluster-randomised trial of improved IYCF and improved WASH on child stunting and anaemia at 18 months of age. 1169 infants born to HIV-negative mothers provided plasma and faecal specimens at 1, 3, 6, 12, and 18 months of age. We measured EED biomarkers that reflect all domains of the hypothesized pathological pathway. Markers of intestinal permeability and intestinal inflammation declined over time, while markers of microbial translocation and systemic inflammation increased between 1–18 months. Markers of intestinal damage (I-FABP) and repair (REG-1β) mirrored each other, and citrulline (a marker of intestinal epithelial mass) increased from 6 months of age, suggesting dynamic epithelial turnover and regeneration in response to enteric insults. We observed few effects of IYCF and WASH on EED after adjustment for multiple comparisons. The WASH intervention decreased plasma IGF-1 at 3 months (β:0.89, 95%CI:0.81,0.98) and plasma kynurenine at 12 months (β: 0.92, 95%CI:0.87,0.97), and increased plasma IGF-1 at 18 months (β:1.15, 95%CI:1.05,1.25), but these small WASH effects did not translate into improved growth.ConclusionsOverall, we observed dynamic trends in EED but few effects of IYCF or WASH on biomarkers during the first 18 months after birth, suggesting that these interventions did not impact EED. Transformative WASH interventions are required to prevent or ameliorate EED in low-income settings.

Reversal of Pathogen-Induced Barrier Defects in Intestinal Epithelial Cells by Contra-pathogenicity Agents.

Environmental enteropathy (EE) is associated with stunting, impairment of responses to oral vaccines, and other adverse health consequences in young children throughout the developing world. EE is characterized by chronic low-grade intestinal inflammation and disrupted epithelial barrier integrity, partly resulting from dysregulation of tight junction proteins, observed in other enteropathies such as celiac disease. During EE, this dysregulation of tight junction expression amplifies translocation of pathogenic bacteria across the intestinal mucosa. The aim was to determine whether enteropathogen-mediated epithelial barrier failure can be ameliorated using contra-pathogenicity therapies. Intestinal epithelial barrier damage was assessed in Caco-2 cells incubated with three important enteropathogens identified in EE patients: Enteropathogenic Escherichia coli (EPEC), Citrobacter rodentium (C. rodentium), and Cryptosporidium parvum (C. parvum). Potential therapeutic molecules were tested to detect effects on transepithelial resistance (TER), bacterial translocation (BT), claudin-4 expression, and regulation of the inflammatory cytokine response. All three enteropathogens compared to uninfected cells, reduced TER (EPEC; p < 0.0001, C. rodentium; p < 0.0001, C. parvum; p < 0.0007), reduced claudin-4 expression, and permitted BT (EPEC; p < 0.0001, C. rodentium; p < 0.0001, C. parvum; p < 0.0003) through the monolayer. Zinc, colostrum, epidermal growth factor, trefoil factor 3, resistin-like molecule-β, hydrocortisone, and the myosin light chain kinase inhibitor ML7 (Hexahydro-1-[(5-iodo-1-naphthalenyl)sulfonyl]-1H-1,4-diazepine hydrochloride); ML7) improved TER (up to 70%) and decreased BT (as much as 96%). Only zinc demonstrated modest antimicrobial activity. The enteropathogens impaired intestinal-epithelial barrier integrity with dysregulation of claudin-4 and increased bacterial translocation. Enteropathogen-mediated damage was reduced using contra-pathogenicity agents which mitigated the effects of pathogens without direct antimicrobial activity.

Association between Malaria Infection and Early Childhood Development Mediated by Anemia in Rural Kenya.

Malaria is a leading cause of morbidity and mortality among children under five years of age, with most cases occurring in Sub-Saharan Africa. Children in this age group in Africa are at greatest risk worldwide for developmental deficits. There are research gaps in quantifying the risks of mild malaria cases, understanding the pathways linking malaria infection and poor child development, and evaluating the impact of malaria on the development of children under five years. We analyzed the association between malaria infection and gross motor, communication, and personal social development in 592 children age 24 months in rural, western Kenya as part of the WASH Benefits environmental enteric dysfunction sub-study. Eighteen percent of children had malaria, 20% were at risk for gross motor delay, 21% were at risk for communication delay, and 23% were at risk for personal social delay. Having a positive malaria test was associated with increased risk for gross motor, communication, and personal social delay while adjusting for child characteristics, household demographics, study cluster, and intervention treatment arm. Mediation analyses suggested that anemia was a significant mediator in the pathway between malaria infection and risk for gross motor, communication, and personal social development delays. The proportion of the total effect of malaria on the risk of developmental delay that is mediated by anemia across the subscales was small (ranging from 9% of the effect on gross motor development to 16% of the effect on communication development mediated by anemia). Overall, malaria may be associated with short-term developmental delays during a vulnerable period of early life. Therefore, preventative malaria measures and immediate treatment are imperative for children’s optimal development, particularly in light of projections of continued high malaria transmission in Kenya and Africa.

Daily Supplementation With Egg, Cow Milk, and Multiple Micronutrients Increases Linear Growth of Young Children with Short Stature

Background:Childhood stunting is the most prevalent public health nutrition problem in low- and middle-income countries. Objective:This study aimed to determine whether daily supplementation in 12–18-mo-old undernourished Bangladeshi children with egg, cow milk, and multiple micronutrients improves linear growth. Methods:In the Bangladesh Environmental Enteric Dysfunction (BEED) study, a community-based intervention study, 12–18-mo-old children with length-for-age z score (LAZ) <1 were supplemented daily with an egg and 150 mL of milk for 90 feeding days, and 1 sachet of multiple micronutrient powder was provided daily for 60 feeding days. The change in LAZ over this period was compared with that in children of the same age and same baseline LAZ who were enrolled in the recently completed Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health (MAL-ED) Dhaka birth cohort study conducted in the same community where no nutrition intervention was provided. Difference-in-difference (DID) analysis was done and the effect size was adjusted for other possible covariates using a generalized estimating equation in a regression model. Results:A total of 472 children with LAZ <1 completed the intervention and data were available for 174 children in the comparison group. Compared with the comparison group, adjusted DID analysis revealed a change in LAZ in the intervention group of +0.23 (95% CI: 0.18, 0.29; P < 0.05). In a subgroup analysis, the changes were +0.27 (95% CI: 0.18, 0.35; P < 0.05) in stunted (LAZ <2) children and +0.19 (95% CI: 0.12, 0.27; P< 0.05) in children at risk of stunting (LAZ -1 to -2). No allergic reactions or other adverse events related to milk and egg consumption were observed. Results:Daily directly observed milk, egg, and multiple micronutrient supplementation may improve linear growth of stunted children. A randomized controlled trial with longer duration of supplementation coupled with an additional intervention aimed at reducing pathogen burden is warranted to confirm these results. This trial was registered at clinicaltrials.gov as NCT02812615.