Schistosoma mansoni infection is associated with changes in gut microbiota in preschool age children in Albertine Region, Uganda

Schistosoma mansoni is a parasitic worm that infects millions of people in sub-Saharan Africa, particularly young children, and causes chronic intestinal disease. This study asked whether infection with this parasite also reshapes the community of microbes living in the gut. Researchers in Uganda compared stool samples from 56 infected preschool-aged children (12–47 months) with 57 uninfected children, using DNA sequencing to profile gut bacteria and computational tools to infer what those bacteria were doing metabolically. Infected children had a more species-rich gut microbiome overall, but the composition was skewed toward pro-inflammatory bacteria while beneficial bacteria that produce short-chain fatty acids (SCFAs)—molecules that nourish the gut lining and dampen inflammation—were depleted. Computational modeling of metabolic pathways suggested that the capacity for energy metabolism and SCFA production was significantly reduced in infected children. This dual hit—more inflammation-promoting microbes and fewer protective ones—could worsen nutritional outcomes and may even help the parasite persist. The findings underscore that S. mansoni infection does more than damage the gut wall directly; it fundamentally destabilizes the microbial ecosystem young children depend on for healthy development.

• Infected children (n=56, median age 36 months) showed significantly higher alpha diversity and species richness (Chao1, Shannon, Simpson indices) compared to uninfected controls (n=57, median age 26 months), suggesting S. mansoni infection is associated with microbial over-richness rather than simple depletion.
• Beta diversity analysis using both UniFrac and Bray-Curtis distance metrics confirmed statistically distinct microbial community structures between infected and uninfected groups (permutation-based p=0.001), indicating infection reshapes overall gut microbiota composition.
• S. mansoni infection was associated with enrichment of pro-inflammatory bacterial taxa alongside depletion of short-chain fatty acid (SCFA)-producing bacteria, and PICRUSt2 functional modeling mapped to the KEGG database revealed significant downregulation of metabolic pathways involved in energy metabolism and SCFA biosynthesis in infected children.

This was a cross-sectional study conducted in the Albertine Region of Uganda enrolling preschool-aged children aged 12–47 months, comparing 56 S. mansoni-infected individuals to 57 uninfected controls. Microbial DNA was extracted from stool samples and sequenced on the Illumina MiSeq v3 platform targeting the V4 hypervariable region of the 16S rRNA gene. Microbial diversity was quantified using alpha diversity metrics (Chao1, Simpson, Shannon) and beta diversity metrics (UniFrac, Bray-Curtis), with functional pathway potential inferred computationally using PICRUSt2 mapped against the KEGG database. No longitudinal follow-up was performed; this is a single time-point comparison.

The cross-sectional design prevents any causal inference: it is impossible to determine whether the observed dysbiosis preceded infection (and may have facilitated it), arose as a consequence of infection, or reflects confounding by unmeasured variables such as diet, sanitation, or co-infections. The median age difference between groups (infected 36 months vs. uninfected 26 months) introduces a potential developmental confound, as the infant gut microbiome undergoes substantial maturation across this window, which may independently explain some diversity differences. Functional pathway predictions via PICRUSt2 are inferred from 16S amplicon data rather than directly measured by shotgun metagenomics or metabolomics, limiting the confidence with which specific metabolic conclusions can be drawn. A longitudinal cohort study—ideally with pre- and post-infection sampling, age-matched controls, and direct metabolite measurement—would be needed to establish directionality and clarify whether anti-helminthic treatment restores a healthy microbial state.

This study extends the growing corpus of research on infection- and disease-driven gut microbiota remodeling catalogued in this platform. It parallels [§86], which also uses sequencing-based microbiome profiling to link gut dysbiosis to disease pathology, albeit in post-stroke cognitive impairment in adults rather than pediatric helminthiasis, reinforcing the cross-condition principle that host perturbations reliably reshape microbial community structure and function. The SCFA-depletion finding directly parallels [§101], which examines gut microbiota–bile acid crosstalk and metabolic dysfunction, since both studies converge on disrupted microbial metabolite production as a downstream consequence of dysbiosis. The study also extends [§87], which investigates how gut microbiota regulates systemic inflammatory and anti-inflammatory responses, by providing a concrete infectious-disease context in which pro-inflammatory taxon expansion and SCFA-producer depletion together predict impaired immune regulation. Finally, the pediatric focus and potential nutritional consequences contextually complement [§25], a systematic review of gut microbiota-modulating interventions in pediatric type 1 diabetes, highlighting that microbiota-targeted interventions in children remain an underexplored translational frontier across multiple disease areas.

• Gut Microbiota Regulates Systemic Inflammatory Response and Compensatory Anti-Inflammatory Response Syndromes by Targeting PF4+ Macrophages in Acute Pancreatitis
  Directly relevant mechanistic parallel: this article examines how gut microbiota regulates systemic inflammatory and anti-inflammatory response syndromes, providing a framework to interpret the pro-inflammatory taxon enrichment and SCFA depletion reported in S. mansoni-infected children.
• Letter to the Editor: Gut microbiota–bile acid crosstalk - Prevotellaceae NK3B31 and 7-ketolithocholic acid drive metabolic benefits of distal bowel resection with preservation of terminal ileum
  Both studies converge on disrupted microbial metabolite production (SCFA and bile acid pathways respectively) as a functional consequence of dysbiosis, making a side-by-side comparison useful for understanding how different disease contexts lead to overlapping metabolic impairment.
• Integrated gut microbiota and metabolome signatures revealed by deep metagenomic sequencing in post-stroke cognitive impairment with type 2 diabetes
  Methodological comparator using deep metagenomic sequencing and metabolomics rather than 16S amplicon sequencing, allowing readers to assess how much additional mechanistic resolution shotgun approaches provide over the PICRUSt2-inferred functional predictions used in this helminth study.
• Gut microbiota-modulating interventions in paediatric type 1 diabetes: a systematic review and meta-analysis
  Provides a pediatric translational counterpoint: this systematic review of microbiota-modulating interventions in children with type 1 diabetes raises the question of whether similar probiotic or dietary strategies could restore SCFA-producing bacteria depleted by S. mansoni infection.
• Microbiota remodeling after bariatric surgery: Procedure-specific dynamics and metabolic implications
  Useful structural contrast—bariatric surgery also drives rapid, reproducible gut microbiota remodeling with measurable metabolic consequences, offering a non-infectious model for comparing the magnitude and directionality of diversity shifts against those observed with parasitic infection.