Thiry Nancy, Beutels Philippe, Van Damme Pierre, Van Doorslaer Eddy
Department of Epidemiology and Social Medicine, Centre for the Evaluation of Vaccination, University of Antwerp, Antwerp, Belgium.
Pharmacoeconomics. 2003;21(1):13-38. doi: 10.2165/00019053-200321010-00002.
Chickenpox infections are generally mild but due to their very high incidence among healthy children they give rise to considerable morbidity and occasional mortality. With the development of a varicella vaccine in the early 1970s and its progressive licensing in many countries, interest in the efficiency of varicella immunisation programmes grew. The objective of this review was to discuss the methodological aspects and results of published economic evaluations of varicella vaccination. From this, we attempted to make recommendations. A computerised search was carried out; 17 full economic evaluations of varicella vaccination were retrieved. The review identified the methodological divergences and similarities between the articles in four areas: study design, epidemiological data, economic data and model characteristics. We assessed to what extent the applied methods conform to general guidelines for the economic evaluation of healthcare interventions and compared the studies' results. The desirability of a universal vaccination programme depends on whose perspective is taken. Despite variability in data and model assumptions, the studies suggest that universal vaccination of infants is attractive to society because large savings occur from averted unproductive days for parents. For the healthcare payer, universal vaccination of infants does not generate savings. Vaccination of susceptible adolescents has been proposed by some authors as a viable alternative; the attractiveness of this is highly dependent on the negative predictive value of anamnestic screening. Targeted vaccination of healthcare workers and immunocompromised individuals appears relatively cost effective. Findings for other target groups are either contradictory or provide insufficient evidence for any unequivocal recommendations to be made. High sensitivity to vaccine price was reported in most studies. This review highlights that some aspects of these studies need to be further improved before final recommendations can be made. First, more transparency, completeness and compliance to general methodological guidelines are required. Second, because of the increasing severity of varicella with age, it is preferable and in some cases essential to use dynamic models for the assessment of universal vaccination strategies. Third, most studies focused on the strategy of vaccinating children only while their results depended heavily on disputable assumptions (regarding vaccine effectiveness and impact on herpes zoster). Since violation of these assumptions could have important adverse public health effects, we suggest pre-adolescent vaccination as a more secure alternative. This option deserves more attention in future analyses.
水痘感染通常症状较轻，但由于其在健康儿童中的发病率极高，会导致相当高的发病率，偶尔还会造成死亡。随着20世纪70年代初水痘疫苗的研制及其在许多国家逐步获得许可，人们对水痘免疫计划的效率越来越感兴趣。本综述的目的是讨论已发表的水痘疫苗接种经济评估的方法学方面和结果。据此，我们试图提出建议。进行了计算机检索；检索到17项关于水痘疫苗接种的完整经济评估。该综述确定了这些文章在四个方面的方法学差异和相似之处：研究设计、流行病学数据、经济数据和模型特征。我们评估了所应用的方法在多大程度上符合医疗保健干预经济评估的一般指南，并比较了这些研究的结果。普遍接种计划是否可取取决于采取谁的视角。尽管数据和模型假设存在差异，但研究表明，对婴儿进行普遍接种对社会具有吸引力，因为可以避免父母的非生产性天数，从而节省大量成本。对于医疗保健支付方来说，对婴儿进行普遍接种不会节省成本。一些作者提议对易感青少年进行接种作为一种可行的替代方案；其吸引力高度依赖于回忆性筛查的阴性预测值。对医护人员和免疫功能低下者进行有针对性的接种似乎相对具有成本效益。其他目标群体的研究结果要么相互矛盾，要么提供的证据不足，无法做出明确的建议。大多数研究报告了对疫苗价格的高度敏感性。本综述强调，在做出最终建议之前，这些研究的某些方面需要进一步改进。首先，需要更高的透明度、完整性以及对一般方法学指南的遵守程度。其次，由于水痘的严重程度随年龄增长而增加，在评估普遍接种策略时，最好使用动态模型，在某些情况下这是必不可少的。第三，大多数研究仅关注儿童接种策略，而其结果在很大程度上依赖于有争议的假设（关于疫苗有效性和对带状疱疹的影响）。由于违反这些假设可能会对公共卫生产生重要的不利影响，我们建议青春期前接种作为一种更安全的替代方案。这一选择在未来的分析中值得更多关注。
