Investigating the causal role of gut microbiota in zoster infection and its complications: A bidirectional Mendelian randomization study

Zoster infection, or herpes zoster (HZ), caused by the varicella-zoster virus (VZV), frequently manifests as painful vesicular rashes and may progress to postherpetic neuralgia (PHN). Observational studies suggest a potential association between gut microbiota changes and both the infection and neuropathic pain, yet causality remains uncertain. This study conducted a bidirectional Mendelian randomization (MR) analysis using summarized data from publicly available genome-wide association studies (GWAS) on the gut microbiota, zoster infection, and PHN. To ascertain causality, we used 5 MR methods centered on Inverse Variance Weighting (IVW), supported by sensitivity analyses, for the robustness of the results. We conducted a bidirectional MR analysis. MR analysis suggested a potential causal relationship between the gut microbiota and zoster infection. A lower risk of HZ was found for the family Bifidobacteriaceae, Eubacterium coprostanoligenes group, genus Prevotella7, and order Bifidobacteriales. In contrast, the genus Lachnospiraceae UCG008 was associated with higher risk. Five types of bacteria were found to protect against PHN. These were from the genus Actinomyces, the genus Family XIII UCG001, the genus Lachnospiraceae NK4A136 group, the genus Parasutterella, and the genus Ruminococcaceae UCG011. Sensitivity analysis confirmed the robustness of the findings. These findings suggest that interventions aimed at modulating specific gut microbiota may offer a novel approach to improving the quality of life of patients with zoster infection and postherpetic neuralgia.