Varicella Zoster (chicken pox) is a highly contagious disease, a centripetal, pleomorphic rash appearing on the first day of the illness and a relatively short course of illness. The crusts from chicken pox lesions don’t contain viable virus and are therefore not infective. Period of infectivity range from a day prior to the illness and up to 5 days after the onset. Children with chickenpox are removed from school or daycare centres for 6 days after the appearance of the rash.