Assessment of environmental exposure factors on child diarrhea and systemic inflammation in the Eastern Cape

An integrated analysis of the fecal metabolome and metagenome reveals the distinct effects of differentially charged nanoplastics on the gut microbiota-associated metabolites in mice

Whether nanoplastics with differential charges cause intestinal impairment via distinct mechanisms remains unclear. We investigated the relationship between fecal metabolites and the gut microbiome, and potential biomarkers thereof, in mice following exposure to differentially charged polystyrene nanoplastics (PS-NPs). Metagenomic analysis revealed that exposure to differentially charged PS-NPs resulted in alterations in the abundances of Bilophila_wadsworthia, Helicobacter apodemus, and Helicobacter typhlonius. A total of 237 fecal metabolites were significantly altered in mice that exhibited intestinal impairment, and these included 10 gut microbiota-related fecal metabolites that accurately discriminated impaired intestinal samples from the control. Additionally, the specific gut microbiome-related fecal metabolite-based model approach for the prediction of intestinal impairment in mice had an area under the curve (AUC) of 1.0 in the PS (without charge) group, an AUC of 0.94 in the PS-NH2 (positive charge) group, and an AUC of 0.86 in the PS-COOH (negative charge) group. Thus, the model showed promising evaluable accuracy for the prediction of intestinal impairment induced by nanoplastics in a charge-specific manner. Our study demonstrates that the fecal metabolome of mice with intestinal impairment following exposure to differentially charged nanoplastics is associated with changes in the gut microbiome. The identified biomarkers have potential application for the detection of intestinal impairment after exposure to negative, positive, or noncharged nanomaterials.

Infection, nutritional status, and body composition: Associations at birth and 6 months postnatally in Soweto, South Africa

INTRODUCTION

The impact of infection on infant nutritional status, body size, and growth is well documented. However, research into the impact of infection on infant body composition is limited. Greater understanding is, therefore, needed on the effects of infection in early life.

METHODS

Associations between a composite morbidity index consisting of the sum of the cumulative tallies for a range of symptoms representing infection and morbidity in the infants and nutritional status (height-for-age (HAZ), and weight-for-height (WHZ)), and body composition (fat-free mass (FFM), fat mass (FM), fat-free mass index (FFMI), and fat mass index (FMI)) at 6 months of age were investigated using hierarchical regression analysis.

RESULTS

The sample comprised data between birth and 6 months postnatally, of 156 infants who were a priori born healthy in Soweto, South Africa. Morbidity, over the cumulative period of birth to 6 months, was associated with lower FMI (β = -1.77) and lower FM (β = -0.61), and conversely with higher FFM (β = 0.94), in infants at 6 months. No associations were found between the morbidity index and FFMI, HAZ, and WHZ. Increased birthweight was associated with a higher FFM (β = 0.66), HAZ (β = 1.14), and WHZ (β = 0.87). Finally, safely managed sanitation facilities, representative of reduced environmental exposure to fecal-oral transmission pathways were associated with a higher HAZ (β = 1.21).

DISCUSSION

Reduction in FMI and FM and exposure to inflammatory cytokines associated with mounting an immune response could alter phenotypic trajectories during to this period of plasticity. From a public health perspective, these results imply that it is important to intensify efforts to prevent infection in infants in the first 6 months postnatally, and that these efforts should concentrate on access to safely managed sanitation facilities.

Water, sanitation, and hygiene vulnerability in child stunting in developing countries: a systematic review with meta-analysis

OBJECTIVES

This study aimed to perform a systematic review and meta-analysis to assess the scientific evidence of the relationship between vulnerability to access to safe drinking water, sanitation, and hygiene (WASH) practices on stunting in children aged <5 years in developing countries.

STUDY DESIGN

This is a systematic review and meta-analysis article to assess the relationship between under-five stunting and WASH vulnerability in developing countries.

METHODS

The systematic review with meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol methodology. The following databases were used: LILACS, MEDLINE (via PubMed), SciELO, Web of Science, ScienceDirect, SCOPUS, and Embase. All original studies identified that related WASH vulnerability to stunting in children aged <5 years in developing countries was included. Three authors performed independently the selection and extraction of data from the articles. The statistical software STATA version 11 was used. Cochran's Q test and Chi-square test (I²) with 95% significance were used to assess the heterogeneity of the studies.

RESULTS

The search resulted in the initial identification of 2047 articles; after reading the abstracts, followed by the full articles, 14 articles were included in the systematic review and eight articles were included in the meta-analysis. The studies selected for the systematic review were published between the years 1992 and 2021 and conducted in eight countries, namely, Ethiopia, India, Indonesia, Bangladesh, Tanzania, Peru, China, and Lesotho. The studies assessed vulnerability to access to WASH on the growth of children aged <5 years. There was a significant difference when relating WASH vulnerability to children's height. The meta-analysis of this study showed that the impact of WASH on child stunting is significant when it comes to lack of sanitation in 72% of the studies.

CONCLUSIONS

The study found that WASH vulnerability contributes to stunting in children aged <5 years in developing countries. Based on our findings, we recommend incorporating WASH strategies, especially sanitation, into the formulation of interventions integrating with health promotion policies for healthy early childhood development.

Climate variability, water supply, sanitation and diarrhea among children under five in Sub-Saharan Africa: a multilevel analysis

Climate variability is expected to increase the risk of diarrhea diseases, a leading cause of child mortality and morbidity in Sub-Saharan Africa (SSA). The risk of diarrhea is more acute when populations have poor access to improved water and sanitation. This study seeks to determine individual and joint effects of climate variation, water supply and sanitation on the occurrence of diarrhea among children under five in SSA using multilevel mixed-effect Poisson regression including cross-level interaction. We merged 57 Demographic and Health Surveys (DHS) from 25 SSA countries covering the period 2000-2019 with climatic data from the DHS geolocation databases. The results of the research indicate that 77.7% of the variation in the occurrence of diarrhea in Sub-Saharan households is due to climatic differences between clusters. Also, a household residing in a cluster with a high incidence of diarrhea is 1.567 times more likely to have diarrhea cases than a household from a cluster with a low incidence. In addition, when average temperature and rainfall increase, households using unimproved sanitation or unimproved water have more cases of diarrhea. For SSA, the results of the multilevel analysis suggest the adoption at both levels; macro (national) and micro (household), of climate change adaption measures in the water sector to reduce the prevalence of diarrhea.

A Structural Equation Model to Decipher Relationships among Water, Sanitation, and Health in Colonias-Type Unincorporated Communities

The colonias along the United States-Mexico border are generally self-built neighborhoods of low-income families that lack basic infrastructure. While some government assistance has provided roads and electricity, water and wastewater services are still lacking in many colonias. This research is the first to collect a comprehensive dataset on water, sanitation, health, and living conditions in these unincorporated neighborhoods through collection of water samples and surveys; 114 households in 23 colonias across three geographically diverse Texas counties are studied. Water quality is assessed via traditional microbial indicators, chlorine, and arsenic. This complex dataset requires an advanced statistical tool to disentangle relationships among diverse factors. Structural equation modeling is utilized to identify relationships among surveyed and measured variables. The model reveals that colonias residents with well/hauled water accurately predict their water quality, while those with treated+piped water tend to think that their water is worse than it actually is. Dwelling quality and connection to sanitary sewers influence perceived health risks and household health, respectively. Furthermore, these communities have an overwhelming need and desire for point-of-use water treatment. This model can inform decision making and may be adapted to probe other questions and social dynamics for water and sanitation in unincorporated communities elsewhere.

Water, sanitation, and hygiene (WASH) factors associated with growth between birth and 1 year of age in children in Soweto, South Africa: results from the Soweto Baby WASH study

Interventions to reduce undernutrition and improve child growth have incorporated improved water, sanitation, and hygiene (WASH) as part of disease transmission prevention strategies. Knowledge gaps still exist, namely, when and which WASH factors are determinants for growth faltering, and when WASH interventions are most effective at improving growth. This study drew cross-sectional data from a longitudinal cohort study and used hierarchical regression analyses to assess associations between WASH factors: water index, sanitation, hygiene index, and growth: height-for-age (HAZ), weight-for-age (WAZ), weight-for-height (WHZ) at 1, 6, and 12 months postpartum among infants a priori born healthy in Soweto, Johannesburg. Household access to sanitation facilities that were not safely managed was associated with a decrease in HAZ scores at 1 month (β = -2.24) and 6 months (β = -0.96); a decrease in WAZ at 1 month (β = -1.21), 6 months (β = -1.57), and 12 months (β = -1.92); and finally, with WHZ scores at 12 months (β = -1.94). Counterintuitively, poorer scores on the hygiene index were associated with an increase at 1 month for both HAZ (β = 0.53) and WAZ (β = 0.44). Provision of safely managed sanitation at household and community levels may be required before improvements in growth-related outcomes are obtained.