Varicella is a highly contagious disease caused by varicella-zoster virus ( VZV) . Vaccination has provided the best means to control infection. A number of countries maintain a universal childhood vaccination policy since 1995, resulting in a dramatic decrease in the incidence, morbidity and mortality related to varicella. In this article, we review the development of varicella Oka vaccine, the research in vaccine efficiency and safety, the molecular mechanism of attenuation, as well as newideas in immunization strategy, summarizing the current advances and limits
of the varicella vaccine since its worldwide application.