Chickenpox Vaccine Loses Effectiveness After One Yearhttps://blogs.mercola.com:443/sites/vitalvotes/archive/2004/02/19/Chickenpox-Vaccine-Loses-Effectiveness-After-One-Year.aspxThe effectiveness of the chickenpox vaccine decreases significantly in the first year after vaccination, and also appears lower if the vaccine is administered to children younger than 15 months of age. The vaccine does not always provide protection, andenCommunityServer 2008.5 SP1 (Debug Build: 31106.3070)