Tick-borne Encephalitis

Residents and travelers to TBE-endemic areas in Central/Eastern Europe, Scandinavia, Russia, China, Japan, South Korea — especially with outdoor exposure (hiking, camping, mountain biking, forestry) during April–November. Endemic areas: Austria, Czech Republic, Germany (Bavaria/Baden-Württemberg), Switzerland, Baltic states, Finland, Sweden, Slovenia, Russia, parts of China/Japan. Occupational: forestry workers, farmers, military personnel. Consider for any traveler spending ≥1 week in endemic rural/forested areas.

Severe allergic reaction to previous dose, egg protein, or any component (FSME-Immun contains trace egg/chicken protein). Moderate to severe acute illness (defer). Autoimmune conditions: relative contraindication — theoretical risk of exacerbation (discuss with specialist).

Very common (≥1/10): injection site pain (45%), induration, headache (20–25%), fatigue (15%), myalgia (12%). Common: fever (>38°C in 5–6% adults, higher in children), nausea, arthralgia, lymphadenopathy. Reactions typically milder after subsequent doses. Rare: neurological events (incidence 1/70,000–1/1,000,000 — lower than with natural TBE infection). Allergic reactions in egg-allergic individuals (very rare with current purification).

Conventional schedule: 3 doses IM (0.5 mL adults, 0.25 mL children). FSME-Immun: doses at 0, 1–3 months, 5–12 months. Encepur: doses at 0, 1–3 months, 9–12 months. Rapid schedule: FSME-Immun: 0, 14 days, 5–12 months. Encepur: 0, 7 days, 21 days (+ booster at 12–18 months). Boosters: first after 3 years, then every 5 years (or every 3 years for ≥60 years). Deltoid (adults) or anterolateral thigh (children).

≥95–99% seroconversion after 3 doses (conventional schedule). Rapid schedule: 90–98% seroconversion after 2 doses. Field effectiveness: ~98% (Austrian mass vaccination program data over 30 years). Duration: ≥10 years with booster schedule. Cross-neutralization between European (FSME-Immun/Encepur) and Far Eastern TBEV subtypes confirmed.

Store at +2°C to +8°C. Do not freeze (suspension may lose potency). Protect from light. Shake well before use. Shelf life: 24 months (FSME-Immun), 24 months (Encepur).

Can be co-administered with hepatitis A, hepatitis B, typhoid, Japanese encephalitis, yellow fever, rabies, and other travel vaccines at different injection sites. No interference with response. No known drug interactions. Immunosuppressive therapy may reduce antibody response — consider checking post-vaccination titers.

Pregnancy: limited human data. Animal studies show no teratogenicity. Use only if exposure risk is high and cannot be deferred. Breastfeeding: unknown if excreted in breast milk; inactivated vaccine expected to be safe. Use if indicated.

Breastfeeding: Likely safe.

No formal studies during breastfeeding. As an inactivated vaccine, TBE vaccination is unlikely to pose a risk to the breastfed infant. European guidelines do not list breastfeeding as a contraindication.

FSME-Immun Junior: 0.25 mL for ages 1–15 years. Encepur Children: 0.25 mL for ages 1–11 years. Same schedule as adults. Higher fever incidence in children (especially after dose 1). Not recommended for <1 year (insufficient data). Consider from 1 year if high-risk travel planned.

Adults ≥60 years: lower and slower antibody response. Booster interval shortened to every 3 years (vs. 5 years for younger adults). Consider checking post-vaccination TBE-specific IgG in elderly immunocompromised patients.

Egg allergy: assess severity; trace amounts of egg protein present (FSME-Immun). Cross-protection between European and Far Eastern TBEV subtypes (confirmed in neutralization studies). TBE-endemic area maps change — verify current epidemiology before recommending. Vaccination does not protect against other tick-borne diseases (Lyme, anaplasmosis). Tick avoidance measures remain important.