# P-1653. Altered Gut Microbiome Composition in Early Childhood COVID-19

## TL;DR

This study finds that young children with COVID-19 have significant changes in their gut microbiome, which could affect immune function and long-term health.

## Contribution

The study identifies specific microbial and immune pathway changes in the gut microbiome of young children with SARS-CoV-2 infection.

## Key findings

- Children with COVID-19 showed increased Bacteroidetes and Firmicutes, and decreased Actinobacteria and Proteobacteria.
- Gut microbiome diversity was reduced in children with COVID-19, indicating microbial dysbiosis.
- Several immune-related pathways were downregulated in the gut microbiome of children with COVID-19.

## Abstract

The gut microbiome plays a crucial role in immune function, and its dysregulation may influence the clinical course of infectious diseases, including coronavirus disease 2019 (COVID-19). Early childhood is a critical period for gut microbiome development, yet data on gut microbiome alterations in young children with COVID-19 remain limited. This study aimed to characterize gut microbiome changes in young children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Stool samples were collected from 18 children under 2 years of age with confirmed SARS-CoV-2 infection and 7 healthy controls between December 2021 and June 2022. Gut microbiota composition was analyzed using 16S rRNA gene sequencing.

In children with COVID-19, the gut microbiome exhibited an increase in Bacteroidetes and Firmicutes, whereas Actinobacteria and Proteobacteria were reduced, with higher abundances of Bifidobacterium, Escherichia, and Streptococcus and lower abundances of Faecalibacterium, Clostridium, and Ruminococcus compared to healthy controls. Children with COVID-19 exhibited reduced alpha diversity, indicating microbial dysbiosis, and significant differences in beta diversity compared to healthy controls. Several immune-related pathways, including NOD-like receptor, IL-17, Fc gamma R-mediated phagocytosis, Th17 differentiation, and Toll/Imd signaling, were significantly downregulated in the gut microbiome of children with COVID-19.

This study highlights significant alterations in the gut microbiome of young children with SARS-CoV-2 infection, emphasizing the need for further research into the potential long-term effects of gut dysbiosis on child health and development.

All Authors: No reported disclosures