MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, London, UK.
Mathematical Modelling of Infectious Diseases Unit, Institut Pasteur, Université Paris Cité, CNRS UMR2000, Paris, France.
Lancet Glob Health. 2023 May;11(5):e759-e769. doi: 10.1016/S2214-109X(23)00117-1.
Several vaccine candidates are in development against MERS-CoV, which remains a major public health concern. In anticipation of available MERS-CoV vaccines, we examine strategies for their optimal deployment among health-care workers.
Using data from the 2013-14 Saudi Arabia epidemic, we use a counterfactual analysis on inferred transmission trees (who-infected-whom analysis) to assess the potential impact of vaccination campaigns targeting health-care workers, as quantified by the proportion of cases or deaths averted. We investigate the conditions under which proactive campaigns (ie vaccinating in anticipation of the next outbreak) would outperform reactive campaigns (ie vaccinating in response to an unfolding outbreak), considering vaccine efficacy, duration of vaccine protection, effectiveness of animal reservoir control measures, wait (time between vaccination and next outbreak, for proactive campaigns), reaction time (for reactive campaigns), and spatial level (hospital, regional, or national, for reactive campaigns). We also examine the relative efficiency (cases averted per thousand doses) of different strategies.
The spatial scale of reactive campaigns is crucial. Proactive campaigns outperform campaigns that vaccinate health-care workers in response to outbreaks at their hospital, unless vaccine efficacy has waned significantly. However, reactive campaigns at the regional or national levels consistently outperform proactive campaigns, regardless of vaccine efficacy. When considering the number of cases averted per vaccine dose administered, the rank order is reversed: hospital-level reactive campaigns are most efficient, followed by regional-level reactive campaigns, with national-level and proactive campaigns being least efficient. If the number of cases required to trigger reactive vaccination increases, the performance of hospital-level campaigns is greatly reduced; the impact of regional-level campaigns is variable, but that of national-level campaigns is preserved unless triggers have high thresholds.
Substantial reduction of MERS-CoV morbidity and mortality is possible when vaccinating only health-care workers, underlining the need for countries at risk of outbreaks to stockpile vaccines when available.
UK Medical Research Council, UK National Institute for Health Research, UK Research and Innovation, UK Academy of Medical Sciences, The Novo Nordisk Foundation, The Schmidt Foundation, and Investissement d'Avenir France.
针对 MERS-CoV，已有几种疫苗候选物正在开发中，该病毒仍是一个主要的公共卫生关注点。在可获得 MERS-CoV 疫苗的情况下，我们研究了在卫生保健工作者中最佳部署疫苗的策略。
我们利用 2013-14 年沙特阿拉伯流行期间的数据，使用推断的传播树（谁感染了谁分析）进行反事实分析，以评估针对卫生保健工作者的疫苗接种运动的潜在影响，其量化指标为避免的病例或死亡比例。我们研究了在疫苗效力、疫苗保护持续时间、动物储主控制措施的有效性、等待时间（针对主动疫苗接种策略，即疫苗接种与下一次暴发之间的时间）、反应时间（针对被动疫苗接种策略）和空间水平（针对被动疫苗接种策略，医院、区域或国家）等条件下，主动疫苗接种策略（即在下次暴发之前接种疫苗）优于被动疫苗接种策略（即响应暴发时接种疫苗）的情况。我们还检查了不同策略的相对效率（每千剂疫苗避免的病例数）。
被动疫苗接种策略的空间范围至关重要。除非疫苗效力显著下降，否则主动疫苗接种策略优于在其医院针对暴发接种疫苗的策略。但是，无论疫苗效力如何，在区域或国家一级的被动疫苗接种策略始终优于主动疫苗接种策略。考虑到每接种一剂疫苗避免的病例数，排名顺序相反：医院级别的被动疫苗接种策略效率最高，其次是区域级别的被动疫苗接种策略，国家级别的疫苗接种策略和主动疫苗接种策略效率最低。如果需要触发被动疫苗接种的病例数增加，则医院级别的疫苗接种策略的效果会大大降低；区域级别的疫苗接种策略的影响是可变的，但如果触发因素的阈值较高，则国家级别的疫苗接种策略的影响得以保留。
当仅对卫生保健工作者进行疫苗接种时，可以大大降低 MERS-CoV 的发病率和死亡率，这突显了有暴发风险的国家在疫苗可用时储备疫苗的必要性。
英国医学研究理事会、英国国家卫生研究院、英国研究与创新署、英国皇家学会、诺和诺德基金会、施密特基金会和法国投资未来署。
