Whole-Genome Analysis of HEV Under Sequential Ribavirin Pressure Reveals Early Minor Variants Predicting Resistance

Ribavirin (RBV) failures in chronic hepatitis E virus (HEV) infection may arise from genomic adaptation, yet the contribution of minor variants remains insufficiently explored. Using a shotgun metagenomics based on next-generation sequencing to obtain the full HEV genome, we analyzed longitudinal HEV populations from sequential clinical samples collected from a patient infected by Paslahepevirus balayani genotype 3c, who underwent three different courses of RBV treatment. Viral diversity increased over time, with most amino-acid substitutions detected at sub-consensus frequencies. Several mutations linked to RBV resistance emerged under treatment pressure. Specifically, D1384N and Y1587F became fixed in the final sampling, while additional substitutions at position 1384 (including D1384T) revealed mutational hotspot. Importantly, D1384N and G1634R were already detectable at low allele frequencies after the first treatment cessation and subsequent rebound, showing that the study of minor variant populations can be early predictors for the development of RBV resistance. These findings underscore the genomic plasticity of HEV under antiviral pressure and highlight the value of deep variant profiling for anticipating RBV treatment failure.