Helicobacter and Herpesvirus detection patterns in pediatric gastric biopsies identify Epstein-Barr virus as a correlate of gastric inflammation

The pediatric gastric mucosa harbors a diverse bacterial and viral community, and its relationship to gastric inflammation remains incompletely understood. We characterized bacterial and viral detection in gastric biopsies from 193 children undergoing endoscopy for chronic abdominal pain, analyzing 507 samples from the antrum, corpus, and incisura angularis. Molecular detection revealed frequent herpesvirus presence, with HHV6 and HHV7 predominating, while Epstein-Barr virus (EBV) was detected in a smaller but consistent subset. HHV6/HHV7 also showed non-uniform anatomical distribution across gastric regions. Multivariable analyses identified Helicobacter pylori ( H. pylori ) as the microorganism most strongly associated with moderate-to-severe chronic inflammation. EBV DNA detection also showed a positive association with inflammation, including in H. pylori -negative patients. Zoonotic non- H. pylori Helicobacter (NHPH) species were commonly detected but did not show consistent population-level associations with inflammation. Overall, these findings support the presence of a heterogeneous gastric microbial landscape in children. Within this landscape, H. pylori remained the microorganism most strongly associated with gastric inflammation, whereas EBV showed the most consistent pattern of association among the remaining microorganisms. These observations generate hypotheses regarding potential interactions among gastric microorganisms that should be addressed in longitudinal and mechanistic studies.