Seroepidemiology of varicella-zoster virus in Korea.

This study was designed to assess the immune status of the Korean population against varicella-zoster virus (VZV) through a seroepidemiologic study. Residual blood samples were collected from diagnostic laboratories throughout Korea. Samples were collected in October 2009 to March 2010 from persons 0-79 yr of age and were tested by ELISA (Enzygnost®; Dade Behring, Schwalbach, Germany). Total seroprevalence in subjects 1-79 yr of age was 89.6%. Seroprevalence increased as age increased from 67.3% in subjects 1-4 yr of age to 94.2% in subjects 10-14 yr of age and in subjects over 20 yr of age seroprevalence ranged from 98.0% to 100%. In children under 1 yr of age, passive immunity waned after birth with none of the subjects having antibodies from 7 months of age and over. Among subjects 1-79 yr of age, susceptible subjects to VZV were mainly under 20 yr of age. These results provide information in understanding the dynamics of varicella disease in Korea, which is important in building up strategies for disease control.