Communicable Diseases Division, Swiss Federal Office of Public Health, 3003 Bern, Switzerland.
Department of Public Health, Environments and Society, London School of Hygiene and Tropical Medicine, London, UK.
J Travel Med. 2022 Mar 21;29(2). doi: 10.1093/jtm/taab158.
In 2006, the Swiss Federal Office of Public Health (FOPH) decided recommending a prolongation of vaccine booster intervals after the third dose for the prevention of tick-borne encephalitis (TBE) from 3 to 10 years.
To ascertain whether this amendment resulted in an increased rate of vaccine breakthroughs, we conducted a retrospective analysis of surveillance data collected 2000-19 by mandatory reporting to the Swiss FOPH. Fractions of breakthroughs [with 95% confidence intervals (CIs)]-0-3 years vs >3-10 years after the third vaccination dose-were compared across time periods and age groups.
Among 3205 notified TBE cases, known vaccination status was reported in 2562 (79.9%), including 103 patients with ≥3 vaccine doses (4.0%). Among those, there were 39 patients who had received the last dose within 3 years and 48 patients in the >3-10 years group. During the 2010-19 period in which the new booster strategy was implemented there were 23 and 38 breakthroughs, respectively, and the annual breakthrough rate was 7.7 (95% CI 5.0-11.7) cases during the first 3 years after the last dose, and 5.4 (95% CI 3.9-7.5) cases in following 7 years. We observed no significant trend of TBE breakthroughs with increasing age. Increasing numbers of TBE and of vaccine breakthroughs over time have been associated with spreading endemicity and higher vaccination coverage in Switzerland.
There is no indication that extended booster intervals resulted in an increased rate of breakthroughs, but there was a marked public health benefit with respect to increased acceptability of TBE immunization in the general population.
2006 年，瑞士联邦公共卫生办公室（FOPH）决定将蜱传脑炎（TBE）疫苗加强针的接种间隔从第三针后 3 年延长至 10 年。
为了确定这一修订是否导致疫苗突破性感染率增加，我们对瑞士 FOPH 强制性报告系统收集的 2000-19 年监测数据进行了回顾性分析。比较了第三针接种后 0-3 年和 >3-10 年两个时间段的突破性感染率（带 95%置信区间[CI]）-按时间和年龄组划分。
在报告的 3205 例 TBE 病例中，已知接种状态的有 2562 例（79.9%），其中 103 例接种了≥3 剂疫苗（4.0%）。在这些病例中，有 39 例最后一剂在 3 年内接种，48 例在 >3-10 年内接种。在实施新加强针策略的 2010-19 年期间，分别有 23 例和 38 例突破性感染，最后一剂接种后 3 年内的年突破性感染率为 7.7（95%CI 5.0-11.7），随后 7 年内为 5.4（95%CI 3.9-7.5）。我们没有观察到 TBE 突破性感染率随年龄增加而增加的趋势。随着时间的推移，TBE 病例和疫苗突破性感染的数量不断增加，与瑞士地方性流行的蔓延和更高的疫苗接种覆盖率有关。
延长加强针接种间隔并没有导致突破性感染率增加的迹象，但普遍人群对 TBE 免疫接种的接受程度显著提高，带来了明显的公共卫生效益。
