疫苗在疾病防控中发挥着极其重要的作用，疫苗接种犹豫对公共卫生造成严重威胁。应对疫苗接种犹豫带来的现实挑战，实现疫苗的公共卫生价值，需要多方利益相关者协作行动，需要疫苗接种政策的支撑。如何使疫苗价值最大化，不仅与科学问题有关，也与疫苗接种政策的伦理可辩护性有关。伦理可辩护性影响着疫苗接种政策是否能够得到公众的支持和公众的行动选择，也影响着广泛的社会共同价值目标的实现。

本研究通过相关的伦理学基本理论的梳理和分析，提出评价疫苗接种政策的伦理框架，针对疫苗接种政策面临的“搭便车”问题、“伤害”问题和“政策工具选择”问题进行了伦理分析与论证，并在此基础上提出相应对策建议。

“搭便车”问题是指因在疫苗接种行动中，个人可能拒绝参与人群免疫屏障的建设和维护而只享受其益处，而产生的搭便车行为的伦理评价问题。疫苗接种的大规模实施可能产生的人群免疫屏障具有公共品的性质。在疫苗接种中，人群免疫屏障的非竞争性是指个体的受益不会影响其他人的受益，人群免疫屏障的非排他性是指无法把某个个体排除在人群免疫屏障提供的保护之外。一种错误观点认为，在有人群免疫屏障保护的情况下，个人的感染风险极低，那么此时拒绝接种可以回避接种可能造成的相关风险，实现个体利益最大化和风险最小化。这一观点所包含的前提中，存在对人群免疫屏障原理的误解。事实上，搭便车策略并不能实现该目的，因为当个人做出是否接种的决策时，无法预先判断人群免疫屏障的既存和持存情况。支持搭便车行为的诡辩，包括“尊重个人选择”以及“要求个人为他人受益而承担风险不公正”的论点，是对尊重和公正原则的谬用，因为尊重自主性和公正的伦理原则所支持的行动都以不伤害他人为前提条件。

“伤害”问题是指因个体疫苗接种犹豫可能给群体带来伤害，而产生的疫苗接种政策对个人决策施加影响的正当性和干预措施的伦理可辩护性问题。个人接种疫苗的决定涉及个人的健康责任、公共卫生安全和人群健康，因而成为一个具有道德和社会意义的问题。疫苗的科学研发与广泛应用，为我们提供了一种有效的预防和控制传染病的手段，但其效果和价值仍然取决于人们对受种义务的认识和履行程度。在伦理视阈下，疫苗接种政策应该为防止伤害而划定个体权益应受保障的空间，可能伤害他人的行动应当受到一定限度的约束。对个人自由的限制只有满足一定条件，才能够得到伦理学辩护。

“政策工具选择”问题是指为实现疫苗接种政策目标而选择不同类型的政策工具时，如何应用疫苗接种伦理框架的问题。政策工具是指实现特定政策目标的具体措施、规定或程序，根据作用机制可划分为规制类、激励类和信息类。对不同类型政策工具面临的伦理挑战进行分析，可为政策工具选择提供参考。规制类工具通过制定法律法规、规章条例等方式对行为加以规范，疫苗接种政策采用该类型政策工具曾取得令人满意的实际效果，并且对人们施以平等地约束，满足了道德直觉对公平性的需求。来自规制类政策工具的外部约束力对于群体做出最优的理性决策是必要的。然而，带有强制性的政策工具常因干涉个人的选择自由而遭到反对。反对干涉自由通常也符合大多数人的道德情感和直觉。因此，每当采用带有强制性的政策工具，都需要更仔细的伦理分析。激励类工具通过积极的激励措施，对行为施加某种非强制性的影响。然而，激励政策也有可能使一些受种者认为他们的权利受其侵犯，尤其是提供经济激励的疫苗接种计划可能会被视为用金钱干扰了人们的自主决策。信息类政策工具通过提供利弊两方面的信息，而对行为加以引导，使之趋向预定目标发展。信息传播新技术，如信息个性化推荐算法，可能为疫苗接种带来巨大助益，同时也存在风险。政策工具的伦理可辩护性与政策工具的类型无关，不同的政策工具各有其伦理方面的优势，也可能包含某种需要注意的伦理风险点。在制定和实施政策时，通常会结合使用不同类型的政策工具，以满足伦理原则的要求并达到更好的效果。决策者需要综合考虑政策目标、伦理原则和社会实际情况，选择最合适的政策工具组合来达到预期的结果。

疫苗接种政策需要不断应对新的挑战，确保人们能够持续获得有效保护。合理的决策既需要在科学上是有效的，也需要能够得到伦理学辩护。制定疫苗接种政策应优先关注社会总体获益，保护脆弱人群，采用多种方式推动个人履行接种疫苗的道德义务，优化政策工具选择。

Vaccines are essential in disease prevention and control, and vaccination hesitancy threatens public health. Addressing the real-world challenges posed by vaccination hesitancy and realizing the public health value of vaccines requires collaborative action by multiple stakeholders and the support of vaccination policies. Maximizing the value of vaccines relates not only to scientific issues but also to the ethical defensibility of vaccination policies. Ethical defensibility affects whether vaccination policies can be supported by the public and their choices of action, as well as the realization of broadly shared societal value goals.

This study proposes an ethical framework for evaluating vaccination policies by compiling and analyzing fundamental ethical theories. It provides a moral justification for the problems of “free-riding” “harm” and “policy tool choice” faced by vaccination policies. Based on the ethical analysis and argumentation on the problems of free-riding, harm and policy tools faced by the vaccination policy, corresponding countermeasures and suggestions are put forward.

The “free-riding” problem refers to the ethical evaluation of free-riding behaviors arising from the fact that individuals may refuse to participate in the construction and maintenance of the immunity barrier of the population in a vaccination campaign and only enjoy its benefits. Population immunization barriers that the mass implementation of vaccination may create are like public goods. In the case of vaccination, the non-competitive nature of the population immunization barrier means that the benefit to an individual does not affect the benefit to others, and the non-exclusive nature of the population immunization barrier means that it is not possible to exclude an individual from the protection provided by the population immunization barrier. One erroneous view is that, in the presence of a population immunity barrier, an individual’s risk of infection is so low that refusal to vaccinate at that time avoids the risks associated with vaccination, maximizing the benefits and minimizing the risks to the individual. There is a misunderstanding of the principles of the population immune barrier in the premises underlying this view. The free-rider strategy does not accomplish that purpose because the pre-existing and persistent population immune barrier cannot be preempted when an individual decides whether to vaccinate. Arguments in favor of free-riding, including “respect for individual choice” and “the injustice of requiring individuals to take risks for the benefit of others” are fallacious uses of the principles of respect and justice because the actions supported by the ethical principles of respect for autonomy and justice are predicated on the principle of The precondition of not harming others.

The question of “harm” refers to the legitimacy of vaccination policies to influence individual decision-making and the ethical defensibility of interventions because of the harm that individual vaccination hesitations may cause to the group. An individual’s decision to vaccinate involves personal health responsibilities, public health safety, and population health and is thus an issue of moral and social significance. The scientific development and widespread use of vaccines provide an effective means of preventing and controlling infectious diseases. However, their effectiveness and value still depend on the extent to which people recognize and fulfill their obligation to be vaccinated. From the ethical perspective, vaccination policy should delineate the space where individual rights and interests should be safeguarded to prevent harm, and actions that may harm others should be subject to certain limits. Restrictions on individual freedom can only be ethically justified if they meet certain conditions.

The issue of “choice of policy tools” refers to the application of the ethical framework for vaccination when choosing between different types of policy tools to achieve vaccination policy objectives. Policy tools refer to specific measures, regulations, or procedures to achieve specific policy objectives and can be categorized as regulatory, incentive, or informational according to their mechanism of action. Analyzing the ethical challenges faced by different policy tools can provide a reference for selecting policy tools. Regulatory policy tools regulate behavior through laws, regulations, rules, and other means. Vaccination policy has achieved satisfactory results by using this type of policy instrument, and it satisfies the need for fairness in moral intuition by imposing equal constraints on people. External constraints from regulatory policy tools are necessary for groups to make optimal rational decisions. However, coercive policy tools are often opposed to interfering with individuals’ freedom of choice. Opposition to interference with freedom is also usually in line with most people’s moral sentiments and intuitions. Therefore, a more careful ethical analysis is required whenever policy tools with coercion are used. Incentive-type tools exert some non-coercive influence on behavior through positive incentives. However, incentive policies also have the potential to make some vaccinees feel that they are violating their rights, and in particular, vaccination programs that offer financial incentives may be perceived as interfering with people’s autonomous decision-making with money. Information-based policy tools guide behavior towards a predetermined goal by providing the pros and cons. New technologies for information dissemination, such as algorithms for personalized information recommendation, may bring significant benefits for vaccination but also risks. The ethical defensibility of policy tools is independent of the type of policy instrument; different policy tools have their strengths and may contain some ethical risk points that require attention. When formulating and implementing policies, a combination of various policy tools is expected to meet the requirements of ethical principles and achieve better results. Policymakers must consider the policy objectives, ethical principles, and social realities to choose the most appropriate combination of policy tools to achieve the desired results.

Vaccination policy needs to continuously address new challenges to ensure that people can continue to receive adequate protection. Sound policymaking needs to be both scientifically valid and capable of being ethically defended. Vaccination policies should be designed to prioritize the overall benefits to society, protect vulnerable populations, use a variety of approaches to promote the moral obligation of individuals to vaccinate and optimize the choice of policy tools.