Review of the United States universal varicella vaccination program: Herpes zoster incidence rates, cost-effectiveness, and vaccine efficacy based primarily on the Antelope Valley Varicella Active Surveillance Project data

► In 2000, varicella incidence dramatically declined to 70% of the prevaccine rate. ► HZ reports significantly increased among adults aged 20-69 years from 2000 to 2001. ► Children with a prior history of varicella demonstrated HZ rates similar to adults. ► By 2002, the efficacy of the varicella vaccination had declined well below 80%. ► HZ morbidity costs have exceeded the cost savings from varicella-disease reductions.