Two key Actinomycetota taxa in the human gut microbiota are associated with Schistosoma mansoni infection burden.

Intestinal schistosomiasis, caused by Schistosoma mansoni, remains a persistent source of morbidity despite ongoing mass drug administration. While parasite egg deposition disrupts host gut homeostasis, the specific effects of varying infection burdens on this microbial ecosystem remain a critical knowledge gap. Understanding these intensity-dependent shifts is vital for elucidating mechanisms of chronic disease progression and potential treatment failures. To address this, the study aimed to identify key microbial taxa associated with gut dysbiosis during S. mansoni infection and to determine their association with helminth infection intensity. Stool samples from 20 infected and 20 uninfected individuals from an endemic rural community in Ghana were analysed. Using the Kato-Katz method, positive samples were stratified by infection intensity: low-moderate (< 400 eggs per gram [EPG], n = 15) and high (> 400 EPG, n = 5). Gut microbiota composition and diversity were assessed via 16 S rRNA amplicon sequencing. While overall ß-diversity did not differ between infected and uninfected groups (PERMANOVA: R²=0.012, p = 0.723), Bifidobacterium abundance was increased in infected samples compared to negatives (p = 0.008). Further analyses revealed that Bifidobacterium (p = 0.003) and Collinsella (p = 0.029) were significantly elevated in low-moderate infections, whereas the Escherichia-Shigella genus was reduced (p = 0.0078). Our findings within our study population indicate that S. mansoni-induced gut dysbiosis is distinctly characterised by infection intensity, with Actinomycetota species assuming importance depending on the infection burden.