[Varicella and herpes zoster incidence prior to the introduction of systematic child vaccination in Navarre, 2005-2006].

Varicella is an acute and highly contagious disease produced by the varicella-zoster virus, which leaves lasting immunity. Herpes zoster is produced by reactivation of a latent infection of the same virus. The introduction of systematic and free vaccination against varicella in children of 15 months in Navarre from 2007 onwards can be expected to produce important epidemiological changes.