When to give the second tick vaccine? - briefly
Give the booster 4–6 weeks after the initial injection, ideally before the start of peak tick activity. If the first dose was administered late in the season, schedule the second dose at least two weeks before expected exposure.
When to give the second tick vaccine? - in detail
The second dose should be administered after the primary immunisation has established a measurable immune response. For most tick‑borne disease vaccines the interval ranges from three to six weeks, but exact timing depends on the product, age group, and exposure risk.
- Standard schedule: 4 weeks after the first injection. This interval is recommended for adult and adolescent recipients of the licensed tick‑borne encephalitis vaccine.
- Accelerated schedule: 2 weeks for high‑risk individuals, such as forest workers or travelers to endemic areas, when rapid protection is required. The shortened interval is approved only for specific formulations that have been validated in clinical trials.
- Pediatric schedule: 6 weeks for children under 12 months, allowing the immune system to mature before the booster.
- Extended interval: 12 weeks for immunocompromised patients who may need a longer period to develop adequate antibody titres before the second dose.
Serological testing can confirm that the first dose has generated a protective level of antibodies; if titres are below the threshold, the booster may be postponed until sufficient immunity is achieved. In any case, the second injection must be completed before the start of the tick season in the region to ensure optimal protection.