Viral deletions among healthy young Chinese adults with occult hepatitis B virus infection

► We investigated the prevalence of occult hepatitis B virus infection among healthy young college students after neonatal vaccination in China and investigated the virological features. ► There is still substantial risk for OBI in China despite neonatal vaccination. ► All deletions which were observed in pre-S, BCP, core and P region may play a direct or indirect role in OBI. ► Deletion in pre-S1 region was considered as a pivotal role in hepatocarcinogenesis and it increased the risk of hepatocellular carcinoma in the cohorts studied.