Breaking the cycle: considerations for a life-course vaccination strategy against varicella-zoster virus.

Varicella-zoster virus (VZV) is a highly contagious virus that manifests as varicella (chickenpox) as primary infection and reactivates as herpes zoster (HZ, shingles), with the potential for severe complications. Vaccines against varicella and HZ are available and highly effective, but recommendations vary between countries. This qualitative review discusses the literature regarding (i) the burden of varicella and HZ; (ii) current approaches to vaccination against VZV-related diseases and reasons why varicella and HZ vaccination may not have been widely implemented, and (iii) real-world evidence and trends from countries with vaccination program experience. Varicella and HZ pose significant burdens. The availability of effective vaccines with established safety profiles means that prevention of both manifestations of VZV disease is now largely possible. Reasons why National Immunization Technical Advisory Groups may not recommend varicella and HZ vaccination programs include cost-effectiveness, considerations relating to the interplay of both diseases, and low awareness of the true disease burden. Nevertheless, real-world evidence from countries with existing vaccination programs is demonstrating positive impacts of vaccination on disease incidence and cost. Including both varicella and HZ vaccines in National Immunization Programs can be an effective life-course strategy to tackle the burden of VZV-related diseases.