In a study published in BMC Medical Ethics in November 2023 the authors present a systematic review of normative arguments made about parental refusal of routine vaccination. Describing the topic as an “ethically contested area”, the researchers searched 9 databases for the period of January 1998 to March 2022. The goal of this publication is to offer “researchers, practitioners, and policymakers” a “synthesis of current normative literature”. In this article we examine the results and how it can support future research to “better understand the role of cultural context in normative judgements about vaccination” and “more comprehensively translate the nuance of ethical arguments into practice and policy”.  

Routine rejections 

The authors acknowledge that “vaccine rejection has existed for as long as vaccines”. Despite the “significant contribution” of childhood vaccination to a decrease in global child morbidity and mortality, some parents reject vaccines for their children. The reasons for this rejection “vary widely” and are often associated with “social setting”. A stated example is parents in high-income settings, among whom 2-3% reject routine childhood vaccines, where factors include previous “bad experiences”, concerns about safety, doubt about either the effectiveness or necessity of vaccines, preference for “alternative” health approaches, or “participation in particular social groups of communities”. 

“Vaccination plays a dual role in disease prevention: it serves to protect the vaccinated individual from disease, and when vaccination rates reach a high enough threshold for some diseases, also protects the broader community – including those who remain unvaccinated – by disrupting disease transmission through herd immunity.” 

This dual role “complicates ethical questions” about vaccine refusal. Health care providers, communities, and governments influence vaccine acceptance “by various means”. For example, interventions like incentives and recommendations or strategies like cost reduction may determine a parent’s decision. On the other hand, mandates can be imposed, and the study acknowledges that these are “not always well-supported”.  

Although there exists a “broad literature” on the ethics of childhood vaccine rejection, the authors claim that there is no systematic review of this literature. Therefore, they “sought to systematically explore and characterise” arguments about parental refusal of routine vaccination. This is intended to inform vaccine policy and practice.  

The review and results 

The survey identified 5,231 publications, of which 822 duplicates were removed; the remaining 4409 records were “screened by title and abstract”. After further eliminations, the resulting group included 117 journal articles, 3 theses, and 1 book. Journal articles included were from 3 main areas or a combination of them: medicine, philosophy or ethics, and law. The articles addressed “two central questions”: 

  1. Whether vaccine refusal was justified (to be known as ‘refusal’ arguments) 
  2. Whether various policy or practice responses to those who reject vaccines are justified (to be known as ‘response’ arguments) 

Most of the papers addressed the ‘response’ arguments (61%), with a small group addressing ‘refusal’ arguments, (19%) and about 18% considering both. Less than 2% had a “different focus”.  

‘Refusal’ arguments 
“On balance, most of the literature argues that it is not justifiable for parents to refuse routine vaccination for their children.” 

Most of the literature that falls into the ‘refusal’ category is based on three key areas of concern: 

  1. Respect for autonomy, the doctrine of informed consent, and the value of liberty 
  2. Consequences for the child and others 
  3. The normative significance of parental trust, distrust, and uncertainty 

These concerns are “not discrete” and “are often weighed against one another, linked by causal claims, or held in tension”.  

Respect for autonomy, the doctrine of informed consent, and the value of liberty 

15 papers from the sample present arguments that vaccine refusal is justified based on respect for parental autonomy, rights, or liberties. Some argue that refusal is justified as a preservation of legal rights or expression of religious freedom. Opposition arguments argue that “considerations regarding respect for autonomy are, or can be, outweighed by the potential harm caused to the child and others by not vaccinating”. These arguments include legal and religious perspectives.  

Consequences for the child and others 
“Most of the literature argues for or against the justifiability of vaccine refusal based on consequences.” 

These consequences include the potential harm from vaccine preventable diseases, or vaccines themselves, as well as the potential benefits from herd immunity. The authors note that herd immunity is “deployed in different ways”. Those who justify vaccine refusal in certain circumstances suggest that in settings with a “high level” of herd immunity, the risk presented by an unvaccinated child is not sufficient to override respect for parental autonomy, and that the benefits of “community protection” do not justify the “individual risk” posed by the vaccine. Furthermore, some argue that “some diseases are not harmful enough to proscribe vaccine refusal” and “vaccine injury contributes to and justifies refusal”.  

On the other hand, arguments that refusal is not justifiable consider the “duty” to contribute to herd immunity as a “public good” or the unfairness of “free riding” on that herd immunity. Additionally, the refusal of “a few” may “undermine herd immunity” and cause harm “to the many”; the greatest risk of this is borne by the most vulnerable. These arguments include those written by authors writing from religious perspectives.  

Another account from a vaccinating parent presents the idea that “harms resulting from non-vaccination” are “blameworthy”. They interpret these harms as an “intentional act of aggression against vaccinated children”. The notion of the “child’s interests” is “frequently” raised. Alongside concerns for the consequences of non-vaccination for the child come concerns for autonomy “in the broad sense of being able to direct one’s life in accordance with one’s values or aims”. 

The “interests of the child” are considered in a general sense as well as a legal sense; this term is used by the authors to imply “the formal ‘best interests of the child standard’”. The legal construction is used on both sides. 

The normative significance of parental trust, distrust, and uncertainty 

The sample included a set of papers written from the perspective of parents who chose not to vaccinate, with many of these contributions seeking to justify vaccine refusal; these justifications were often “grounded in distrust”.  

“They call into question vaccine safety and effectiveness, and the accuracy of the reporting of adverse events following immunisation. They claim financial conflicts, constructing clinicians, clinical medicine, and/or regulatory agencies as untrustworthy or non-credible.” 

Empirical studies of non-vaccinators are used to support parental preferences for “natural infection” over a vaccine. However, non-vaccinating parents were not alone in this line of argument; some authors referred to the “lack of absolute certainty” of vaccine safety, especially regarding newer vaccines. This argument “depicts vaccine proponents as driven by commercial interests”, which permits mistrust and refusal

“Contra this, one paper asserts that refusal on the grounds of mistrust of government or medicine is not justifiable, as it is inconsistent with the scientific evidence and the well-established regulatory processes in place.”  
‘Response’ arguments 

The literature examines four main responses to non-vaccination: 

  1. Government mandate policies and other coercive policies 
  2. Exemptions to mandate policies 
  3. Individual practitioner and medical practice responses 
  4. Withholding health resources 
“Much like the refusal arguments, some response arguments are absolute in their position, while others advocate weighing competing values in a context-specific way.” 
Respect for autonomy, the doctrine of informed consent, and the value of liberty 

Just as with the literature on refusal, many arguments about policy and practice responses to non-vaccinating parents “depend on the interrelated concepts of respect for autonomy, informed consent, and liberty”.  

A handful of papers engage with the issue of practitioners vaccinating against parents’ will, arguing that “forced vaccination by healthcare providers violates parents’ autonomy and/or the ethical requirement for informed consent”. Some authors offer alternatives to forced vaccination, such as rebuilding trust. However, proponents of forced vaccination use the harm principle and the ‘best interest of the child standard’ to justify their position. 

Another group of papers draw on autonomy or liberty justifications in comparison with harm or risk of harm considerations.  

“Arguments justifying mandates are often legal in nature and use, for example, the harm principle or case law to argue that the freedom or liberty to choose not to vaccinate is limited by the risk of ill health and/or death to the child or others.”  

One author suggests that legal actions should be brought against parents who “harm others by refusing vaccination”. The idea is that this would “discourage refusal” and “compensate victims” if claims are successful. Others argue that mandates are justifiable if the “exercise of liberty rights poses a threat to public health”.  

Some arguments that mandates are not justifiable rely on arguments about risk of harm, yet many make arguments from the perspective of autonomy, informed consent, and personal liberty. One author suggests that even if mandates improved vaccination rates, they “damage trust” and make refusers “more steadfast in their decision” so are unsustainable. A few authors present “middle-ground positions” that are “autonomy- or liberty-preserving” such as persuasion or weakly enforced mandates. Others argue that “policy responses should take the least coercive approach that is feasible and effective”. This argument seeks to “balance the needs of the individual with public health”.  

Authors who support conscientious objection to mandates argue that these provisions “contribute to the collective good of a culture of respect for autonomy” or “reflect the ‘American ideal’ of personal freedom”. On the other hand, those opposed to these provisions argue that challenges to mandates based in religious freedom have failed in case law.  

“Authors disagree about whether certain policies or practice responses do, or do not, respect autonomy or uphold important liberties.”  

The notion of “nudges” is considered “autonomy-preserving” with some weighing “multiple normative considerations”. However, some consider the “invasive nature of immunisation” a reason for increased need for “independent and informed decision making”.  

Consequences for the child and others 
“Many of the arguments in this literature consider individual and collective consequences…and propose that these may override other normative considerations.” 

The paper implies that “risk and prevention of harm is particularly pertinent”. Arguments about mandates often feature “concern about consequences” such as increased vaccination rates leading to fewer disease outbreaks and associated harms. Mandates are occasionally justified by the “duty to contribute to herd immunity”. This includes under the “clean hands principle”.  

Others argue that mandates are not necessary to achieve high levels of population immunity, from which “state coercion is unjustified”. Mandate opposition also includes arguments that vaccine safety is not absolute or that mandates are a “disutility”.  

“Consequences to the child and others are used to justify whether responses should be applied in general practice settings.” 

For example, one paper considers the consequences of treating non-vaccinating families for general practitioners, suggesting that practices that care for unvaccinated children should disclose this to other patients.  

A “small body of literature” examines the responsibility for the consequences of non-vaccination to make arguments about responses to non-vaccination. Examples include an article that “seeks to justify discriminating against unvaccinated children with a vaccine preventable disease by limiting their access to health resources”. This relies on precedents like surgery being denied to obese people or smokers. The implication is that “those who contribute to their own ill-health” are not deserving of healthcare.  

“Some critiques of policy or practice responses to non-vaccination emphasise that these responses can have inequitable effects and argue that this is unjustifiable.” 

In these cases, “exemption policies are a key focus” with some arguing against exemptions to mandates on the grounds that these “unevenly distribute the risks and benefits of vaccinations”. These authors claim that the “inaction of a few compromises the health of the most vulnerable” or “disenfranchises those with medical contraindications for vaccines”.Some authors who oppose coercive mandates or practice dismissal for non-vaccination critique these responses as having inequitable effects.  

The duty of practitioners and the state 

Several papers consider the duties of practitioners and duties of the state to respond to non-vaccination in “ways that go beyond simply weighing up consequences, implications for autonomy or freedom, or equity of impacts”.  

Duties for practitioners include protecting a child from their parent’s beliefs, if the beliefs are likely to cause harm, and protecting patients in the waiting room from risks posed by non-vaccinating patients. On the other hand, some authors consider a health professional’s obligation to provide healthcare in the best interest of the child despite the parent’s decision, which counters practice dismissal.  

Some assert that the state is “obliged” to discourage non-vaccination for reasons included a “fundamental duty” to protect society, a responsibility to “protect herd immunity as a common good or to reduce social and financial burdens and costs”. Some arguments focus on exemptions, proposing that states can’t justify such exemptions because the government’s interest in protecting society “outweighs the individual’s interest” or because “vaccination is a social and moral good owed by a society to its children”.  

So what? 

At the end of a lengthy review, which we have merely summarised above, the authors highlight an “opportunity for interdisciplinary collaboration” to “widen the scope and reach of normative arguments about non-vaccination”. Although arguments about the justifiability of non-vaccination and “what should be done about it” can “positively influence” routine vaccination rates, they can also “alienate non-vaccinating families” unless they are deployed “with their perspectives in mind”.  

If you’ve made it this far and still have the energy to engage with what you’ve read, do let us know your thoughts on the paper, which you can access in full here. We understand that the issues explored are contentious, so we are interested in thoughtful responses. In particular, if you work in vaccine uptake and deployment how might this inform your work? For more on research into vaccine attitudes and practices do subscribe to our weekly newsletter here.