Antiviral prophylaxis for preventing herpes zoster in hematopoietic stem cell transplant recipients: A systematic review and meta-analysis

The optimal duration of prophylaxis for the varicella-zoster virus following hematopoietic stem cell transplantation (HSCT) remains unclear. The purpose of this study was to systematically review the available literature to determine the optimal duration of antiviral prophylaxis for preventing herpes zoster (HZ) in allogeneic and autologous HSCT recipients. The MEDLINE and EMBASE databases were searched to identify relevant studies. The relative risk (RR) of HZ was calculated using fixed effects or random effects models depending on heterogeneity across the included studies. We analyzed six observational studies comprising a total of 3420 patients. In all HSCT recipients, the overall incidence of HZ in the prophylaxis group and the control group was 7.8% and 25.6%, respectively, with a pooled RR of 0.31 (95% CI, 0.26–0.37). The incidence of HZ in the subgroup wherein prophylaxis was given for at least 1 year and in the subgroup wherein prophylaxis was given for less than 1 year was 2.1% and 15.4%, respectively, with a pooled RR of 0.23 (95% CI, 0.04–1.39). Taken together, our results demonstrate that antiviral prophylaxis can significantly reduce HZ in HSCT recipients, and suggests that long-term prophylaxis given for at least 1 year may be recommended for better preventive effects.