THE changing seroepidemiology of varicella in Japan: 1977-1981 and 2001-2005.

We conducted an anti-varicella-zoster virus antibody seroepidemiologic survey comparing the pre- and postvaccine eras of 1977-1981 and 2001-2005. For each period, 828 samples were measured by enzyme immunoassay test and compared. The differences from 1-year-old to high-school aged children were statistically significant. The introductions of optional varicella immunization and lifestyle changes for children were considered influencing factors.