Varicella vaccine (Varivax, Merck) is derived from livevirus from a child with natural varicella. The virus has beenattenuated by passage through a series of guinea pig andhuman cell cultures. The final preparation is a lyophilizedlive, attenuated virus. The antigen form is whole virus. Theantigen type is protein. The vaccine is well tolerated, withpain and redness at the injection site as the only side effects.The vaccine has shown tremendous success in reducing infections.Indications are the following:
? The vaccine is recommended for children 12 months to 12years old as a single dose.
? Adults who are exposed to chickenpox should continue toreceive VZIG.
? In elderly persons, varicella vaccine can boost immunity tovaricella-zoster virus and may prevent or attenuate herpeszoster (shingles) attacks.