In:
BMJ Open, BMJ, Vol. 12, No. 4 ( 2022-04), p. e061228-
Abstract:
To estimate effectiveness of tickborne encephalitis (TBE) vaccination by time interval ( 〈 5, 5–10 and 10+years) postvaccination. Design A retrospective, matched case–control study Participants Cases—all adult (age 18–79) TBE cases in Switzerland reported via the national mandatory disease reporting surveillance system from 2006 to 2020 (final n=1868). Controls—community controls from a database of randomly selected adults (age 18–79) participating in a 2018 cross-sectional study of TBE vaccination in Switzerland (final n=4625). Primary outcome measures For cases and controls, the number of TBE vaccine doses received and the time since last vaccination were determined. Individuals were classified as being ‘unvaccinated’ (0 doses), ‘incomplete’ (1–2 doses) or ‘complete’ (3+ doses). Individuals with ‘complete’ vaccination were further classified by time since the last dose was received ( 〈 5 years, 5–10 years or 10+ years). A conditional logistic regression model was used to calculate vaccine effectiveness (VE: 100 × [1−OR]) for each vaccination status category. Results VE for incomplete vaccination was 76.8% (95% CI 69.0% to 82.6%). For complete vaccination, overall VE was 95.0% (95% CI 93.5% to 96.1%). When the most recent dose was received 〈 5 years prior VE was 91.6% (95% CI 88.4% to 94.0%), 95.2% (95% CI 92.4% to 97.0%) when the most recent dose was received 5–10 years prior, and 98.5% (95% CI 96.8% to 99.2%) when the most recent dose was received 10+ years prior. Conclusions That VE does not decrease among completely vaccinated individuals over 10+ years since last vaccination supports the longevity of the protective response following complete TBE vaccination. Our findings support the effectiveness of 10-year TBE booster intervals currently used in Switzerland.
Type of Medium:
Online Resource
ISSN:
2044-6055
,
2044-6055
DOI:
10.1136/bmjopen-2022-061228
Language:
English
Publisher:
BMJ
Publication Date:
2022
detail.hit.zdb_id:
2599832-8
