Live Attenuated Varicella Vaccine: Prevention of Varicella and of Zoster

Abstract

Michiaki Takahashi developed the live attenuated varicella vaccine in 1974 . This was the first, and is still the only, herpesvirus vaccine. Early studies showed promise, but the vaccine was rigorously tested on immunosuppressed patients because of their high risk of fatal varicella; vaccination proved to be lifesaving. Subsequently, the vaccine was found to be safe and effective in healthy children. Eventually, varicella vaccine became a component of measles mumps rubella vaccine, 2 doses of which are administered in the USA to ~90% of children. The incidence of varicella has dropped dramatically in the USA since vaccine-licensure in 1995. Varicella vaccine is also associated with a decreased incidence of zoster and is protective for susceptible adults. Today, immunocompromised individuals are protected against varicella due to vaccine-induced herd immunity. Latent infection with varicella zoster virus occurs after vaccination; however, the vaccine strain is impaired for its ability to reactivate.

Keywords: anti-viral therapy; fluorescent antibody to membrane antigen (FAMA); latency; leukemia; reactivation; varicella zoster virus.

Figure 1.

Centers for Disease Control and Prevention reported incidence of varicella in 4 representative states 1990–2014. Varicella-zoster virus was attenuated and vOka was reported as a potential live attenuated vaccine in 1974, testing began in immunocompromised children in 1979, the efficacy and safety of the live attenuated varicella vaccine in immunocompromised and healthy children were reported in 1983–1984, and the vOka-based vaccine was finally licensed in the United States in 1995. The efficacy of the vaccine and the 2006 recommendation for a second dose are illustrated in the figure.