Association between Helicobacter pylori and Epstein–Barr virus co-infection and gastric cancer risk: a systematic review and meta-analysis

BACKGROUND: Co-infection with Helicobacter pylori (H. pylori) and Epstein-Barr virus (EBV) has been demonstrated in clinical studies; however, its association with gastric cancer (GC) remains uncertain. AIMS: This study aims to assess and establish evidence linking H. pylori and EBV co-infection to an increased risk of GC development. DESIGN: A meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. METHODS: We conducted a meta-analysis study to investigate the pooled odds ratios (ORs) for individual infections and co-infections, and their association with the risk of GC development. RESULTS: EBV infection was more frequent in patients with GC than in non-GC patients (OR 4.98, 95% confidence interval (CI) 3.17-7.85, P < 0.0001). H. pylori infection was associated with a significantly increased GC risk compared with a control group excluding gastritis cases (OR 1.42, 95% CI 1.02-1.99, P = 0.03). Nevertheless, the random-effects model revealed that the pooled odds of co-infection were significantly elevated (OR 2.57, 95% CI 1.65-4.01, P < 0.0001). CONCLUSIONS: Both H. pylori and EBV infections increase the risk of developing GC. The co-infection of H. pylori and EBV was linked to a 2.57-fold higher risk of GC, indicating the significance of incorporating both infections into diagnostic and treatment approaches for GC.