Survey of antibody levels to varicella-zoster virus in healthy population in Shanghai

Objective To understand the antibody levels to varicella-zoster virus in healthy population in Shanghai. Methods Totally 2001 serum samples were collected from healthy people aged from 1 to 40 years in some areas of Shanghai to detect varicella IgG antibodies by ELISA. Results The overall positive rate of varicella antibody was 57.57%, the GMC of varicella antibody was 171.15 mIU/ml. In the eight age groups, the positive rate rose with age. In people less 18 years old the positive rates ranged from 41.90% to 66.45%, the GMCs ranged from 77.23 mIU/ml to 269.59 mIU/ml. In age group 19-29 years the positive rate was 85.12% and the GMC was 610.06 mIU/ml. In age group 30-40 years the positive rate of was 96.25% and the GMC was 953.30 mIU/ml. The age specific positive rates and the concentrations of varicella antibody had significant differences between the residents in urban and suburb areas, which were, in age group 1-3 years, dramatically higher in suburb residents than those in urban residents. The GMC of people who received varicella vaccination was 178.55 mIU/ml,while the GMC of those receiving no vaccination was 76.74 mIU/ml, the difference was statistical significant. Conclusion Children aged from 1 to 6 years are susceptible to varicella. The varicella vaccination should be strengthened in this age group and two-dose regimen is recommended.