Cost Effectiveness Analysis of influenza vaccination for people aged 65 or older in Japan

流感流行每年在世界各地爆发，尽管其程度和严重程度差别很大。众所周知，反复出现的流行病会造成疾病，扰乱学校、公司和其他地方的工作。虽然流感影响整个人口，但65岁及以上的个人或已有疾病的人，病情严重到需要住院或死亡的风险更高。随着人口老龄化的发展，这些人的数量在发达国家正在增加。因此，他们面临着流感的严重发病率和死亡率问题。2001年12月，日本启动了一项由政府发起的以年龄为基础的全国流感免疫计划。根据这一方案，65岁及以上的每个人都有权获得流感疫苗接种补贴。为目标人群中自愿接种疫苗的人接种一剂疫苗，部分费用将由公共开支支付。研究表明，在一些国家或地区，针对65岁及以上人群的基于年龄的流感疫苗接种计划可以节省成本或具有成本效益，但日本目前的免疫计划的成本效益尚未报道。在这项研究中，我们进行了经济评估，以详细调查以下两个问题。A)当前的补贴策略是否有效？B)是否有其他更有效的免疫策略？建立决策分析模型，对两种基于年龄的免疫规划和两种基于风险的免疫规划的成本和效果进行研究。通过一系列敏感性分析和蒙特卡罗模拟，我们的研究表明，从社会角度来看，1)日本目前65岁及以上人群的流感疫苗接种计划具有成本效益（基本情况下为6282美元/YOLS）， 2)基于风险的策略比基于年龄的策略具有更有利的增量成本效益比；然而，基于风险和基于年龄的免疫策略都具有合理的成本效益。少

Epidemics of influenza break out annually throughout the world, although their extent and severity vary widely. Recurring epidemics are known to have consequences such as morbidity that disrupts work in school, company, and elsewhere. Although influenza affects entire population, individuals, such as persons aged 65 years and over, or persons with pre-existing disease are at higher risk of becoming serious enough to be hospitalized or die. The number of those individuals is increasing in developed countries, as the aging of population progresses. Consequently, they confront with the problem of serious morbidity and mortality from influenza.Japan launched a government-founded age-base national influenza immunization program in December 2001. Under this program, every person aged 65 and over is entitled to a subsidy for influenza vaccination. One-dose of vaccination administrated to a voluntary vaccinee in the target population will be paid partially by public expenditure.Studies have re … More ported that age-base influenza vaccination program to those aged 65 years or older to be cost-saving or cost-effective in some countries or regions, but cost-effectiveness of the current immunization program in Japan has not been reported. In this study we performed an economic evaluation to investigate the following two questions in detail. A) Is the current subsidy strategy efficient? B) Is there any alternative strategy of immunization which could be more efficient?A decision-analytic model was constructed to investigate the cost and effectiveness of two age-base immunization programs and two risk-base immunization programs. Accompanied by a series of sensitivity analyses and Monte Carlo simulation our study demonstrates that from the perspective of society, 1) current influenza vaccination program for people aged 65 and over in Japan is cost-effective from the perspective of society (US$6, 282/YOLS in base case), 2) risk-base strategy has favorable incremental cost-effective ratios than age-base strategy ; however, both of risk-base and age-base immunization strategies are reasonably cost-effective. Less