Adults who are seronegative to varicella-zoster virus are recommended to receive either varicella or zoster vaccine

More than 97% of older people in Australia are seropositive to varicella-zoster virus (VZV) from previous natural infection,¹⁵ even if they cannot recall having varicella at a younger age. 

Adults who are VZV-seronegative on laboratory testing and have no history of age-appropriate varicella vaccination may receive either:

• 2 doses of varicella vaccine (this is preferable — see Varicella), or
• 1 dose of zoster vaccine (if aged ≥50 years)

In some small studies, high-dose VZV-containing vaccine (comparable to Zostavax) was given to healthy VZV-seronegative adults and previously infected adults. The limited data suggest that the vaccine was well tolerated and immunogenic in seronegative people, but the incidence of self-limited injection site reactions may be slightly higher than in seropositive people.^16,17 There are no specific studies of Zostavax safety in VZV-seronegative adults who have mild to moderate immunocompromising conditions. A cautious assessment of risk factors in these adults, both underlying disease and medication(s), is required.