High Quality Content by WIKIPEDIA articles! The varicella vaccine is a live (attenuated) virus administered to protect against the viral disease commonly known as chickenpox caused by the varicella zoster virus (VZV). The varicella vaccine is marketed as Varivax in the U.S. by Merck and globally as Varilrix by GlaxoSmithKline. Another vaccine that is known as Zostavax is simply a larger-than-normal dose of Varivax, and is used to reduce the risk of shingles (also called herpes zoster) and postherpetic neuralgia that are caused by the same virus.