Commentary:
Toward a pragmatic TBE vaccine schedule – a task for NITAGs

The tick-borne encephalitis (TBE) vaccine was first licensed in 1976, at a time when the disease was, and remains, comparatively rare incidence in Austria is approximately 7 cases per 100,000 population. Because of this low incidence, traditional efficacy studies—requiring large populations and sufficient case numbers—were not feasible at the time of licensing, nor are they practical today (see snapshot week 24/2025). Immunogenicity and effectiveness data Initial licensing of TBE vaccines solely relied on immunogenicity data, specifically antibody titers measured by ELISA and neutralization assays, rather than direct clinical efficacy endpoints and protection. However, over subsequent decades, effectiveness studies in various populations and using various study designs have consistently shown protection rates between 82% and 97% after three doses of vaccine. These real-world data have provided robust confirmation of the vaccine’s protective benefit, even in the absence of classical efficacy trials. The proliferation and complexity of schedules As highlighted by Michael Bröker and others, the TBE...