Zhang Xu-Sheng, Ong Jason J, Macgregor Louis, Vilaplana Tatiana G, Heathcock Simone T, Mindlin Miranda, Weatherburn Peter, Hickson Ford, Edelstein Michael, Mandal Sema, Vickerman Peter
Statistics, Modelling and Economics, Data, Analytics & Surveillance, UK Health Security Agency, UK.
University of Bristol, Bristol, UK.
Lancet Reg Health Eur. 2022 Jun 17;19:100426. doi: 10.1016/j.lanepe.2022.100426. eCollection 2022 Aug.
Despite being vaccine-preventable, hepatitis A virus (HAV) outbreaks occur among men who have sex with men (MSM). We modelled the cost-effectiveness of vaccination strategies to prevent future outbreaks.
A HAV transmission model was calibrated to HAV outbreak data for MSM in England over 2016-2018, producing estimates for the basic reproduction number (R) and immunity levels (seroprevalence) post-outbreak. For a hypothetical outbreak in 2023 (same R and evolving immunity), the cost-effectiveness of pre-emptive (vaccination between outbreaks among MSM attending sexual health services (SHS)) and reactive (vaccination during outbreak among MSM attending SHS and primary care) vaccination strategies were modelled. Effectiveness in quality-adjusted life-years (QALYs) and costs were estimated (2017 UK pounds) from a societal perspective (10-year time horizon; 3% discount rate). The incremental cost-effectiveness ratio (ICER) was estimated.
R for the 2016-2018 outbreak was 3·19 (95% credibility interval (95%CrI) 2·87-3·46); seroprevalence among MSM increased to 70·4% (95%CrI 67·3-72·8%) post-outbreak. For our hypothetical HAV outbreak in 2023, pre-emptively vaccinating MSM over the preceding five-years was cost-saving (compared to no vaccination) if the yearly vaccine coverage rate among MSM attending SHS was <9·1%. Reactive vaccination was also cost-saving compared to no vaccination, but was dominated by pre-emptive vaccination if the yearly vaccination rate was >8%. If the pre-emptive yearly vaccination rate fell below this threshold, it became cost-saving to add reactive vaccination to pre-emptive vaccination.
Although highly transmissible, existing immunity limited the recent HAV outbreak among MSM in England. Pre-emptive vaccination between outbreaks, with reactive vaccination if indicated, is the best strategy for limiting future HAV outbreaks.
NIHR.
尽管甲型肝炎病毒（HAV）感染可通过疫苗预防，但男男性行为者（MSM）中仍会发生HAV疫情。我们对预防未来疫情的疫苗接种策略的成本效益进行了建模。
根据2016 - 2018年英格兰MSM的HAV疫情数据校准了HAV传播模型，得出疫情后基本再生数（R）和免疫水平（血清阳性率）的估计值。对于2023年的假设疫情（相同的R和不断变化的免疫力），对先发制人（在性健康服务机构（SHS）就诊的MSM在疫情间隔期进行疫苗接种）和反应性（在SHS和初级保健机构就诊的MSM在疫情期间进行疫苗接种）疫苗接种策略的成本效益进行了建模。从社会角度（10年时间范围；3%贴现率）估计了质量调整生命年（QALYs）的有效性和成本（2017年英镑）。估计了增量成本效益比（ICER）。
2016 - 2018年疫情的R为3.19（95%可信区间（95%CrI）2.87 - 3.46）；疫情后MSM中的血清阳性率升至70.4%（95%CrI 67.3 - 72.8%）。对于我们假设的2023年HAV疫情，如果在性健康服务机构就诊的MSM的年度疫苗接种覆盖率<9.1%，在过去五年中对MSM进行先发制人疫苗接种是节省成本的（与不接种疫苗相比）。与不接种疫苗相比，反应性疫苗接种也节省成本，但如果年度疫苗接种率>8%，则被先发制人疫苗接种所主导。如果先发制人年度疫苗接种率低于此阈值，在先发制人疫苗接种基础上增加反应性疫苗接种就会节省成本。
尽管HAV传播性很强，但现有的免疫力限制了近期英格兰MSM中的HAV疫情。在疫情间隔期进行先发制人疫苗接种，并在必要时进行反应性疫苗接种，是限制未来HAV疫情的最佳策略。
英国国家卫生研究院（NIHR）
