Seroprevalence and force of infection of varicella-zoster virus in Luxembourg.

A serological prevalence survey was carried out in Luxembourg during 2000-2001 to determine the antibody status of the Luxembourg population against vaccine-preventable infections including varicella-zoster virus (VZV). ELISA tests performed on 2679 sera indicated that 96 (3.6%) of the study population were seronegative. Age-specific seroprevalence rose rapidly from approximately 70% at age 4 years to 90% at age 6 years to 95% at age 12 years. Significant heterogeneity of seroprevalence was observed between the six different primary schools. For age groups 0-5, 6-11 and 12+ years, we estimated an annual force of infection of 0.361 [95% confidence interval (CI) 0.31-0.415)], 0.204 (95% CI 0.12-0.29) and 0.05 (95% CI 0.024-0.082) respectively. Our results indicate that transmission of VZV is highest in children below the age of 6 years and that much lower levels of VZV transmission occur in secondary schools and throughout adulthood.