Protective Effect of Immunization againstChickenpox

Overview

In a group of student volunteers vaccinated at the age of 13–17 years with vaccine produced bySmithKline Beecham Biologicals which contains the live attenuated strain of the Oka virus ofvaricella zoster the period of the protective effect of vaccination was assessed.In the course of 310 000 man-days of detailed investigation the authors revealed in 55 vaccinatedsubjects close exposure to a patient with varicella, and six of the vaccinated subjects contracted thedisease after exposure. In the course of the subsequent three years no further case of varicella wasrecorded. Subjects vaccinated only by a single dose of the vaccine with low post-vaccination levelsof specific antibodies contracted the disease.

Key words:
vaccination against varicella – protective effect.