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Current Drug Safety, 2015, 10, 9-15 9

Risk Communication of Vaccines: Challenges in the Post-Trust Environment

Frederic Bouder *

Department of Technology and Society Studies, Maastricht University, Maastricht, The Netherlands

Abstract: Highly publicised vaccine scares and recent debates about the risks suggest that public trust in immunisation

programmes is fragile. For instance, the recent outbreak of Measles in Wales was the direct result of almost fifteen years

of distrust for the MMR vaccine in the UK. This article shows how the latest science on risk communication will help

critical actors, especially policy-makers, to build trust when they communicate risks to citizens and patients. The article

offers policy advice on risk communication based on the results of three vaccines case studies. Five procedural principles

which were developed for the UK government – the so-called “five As” of public risk communication are used to

structure the discussion. Conclusions and recommendations suggest ways to move forward and build a two-way proactive

risk communication practice.

Keywords: Hepatitis B, HPV, MMR, policy, regulation, risk communication, trust.

INTRODUCTION

In most countries, vaccination is fully or partially compulsory and is driven by nationally and internationally sponsored programmes. Funding and policy commitment have been critical factors in the success of essential global health commitments, such as the near-eradication of polio [1]. Yet, in the internet age and the 24/7 news society, highly publicised vaccines scares – from Measles Mumps and Rubella (MMR) [2, 3], to Hepatitis B [4, 5] and Human papillomavirus (HPV) vaccines [6-8]– suggest that public trust in immunisation is fragile. Expert messages may no longer fare well within significant segments of the population. In Europe, this phenomenon can be traced back to the health scandals of the 1990s – most prominently the BSE [9] and Human Immunodeficiency Virus (HIV) contaminated blood disasters [10]. Controversies have challenged expert-based decision models and led to a European “post-trust” environment [11]. Key features of the emerging post-trust society include a loss of faith in government, the growth of scientific pluralism and the greater impact of the media and the internet on public perception.

Government agencies often struggle to maintain evidence-based and proportional policy responses when they are confronted with vaccine controversies [5]. When this occurs in developing countries the disastrous impact on public health becomes particularly worrisome [12, 13]. In Europe, recent HPV controversies show that large sections of the public are more concerned about product safety and ethics than public health objectives [14]. The success of ongoing and future (e.g. anti-HIV vaccine [15]) immunisation programmes demands that national and international agencies prepare themselves to address society’s questions and concerns. The success of future

*Address correspondence to this author at the Maastricht University, Department of Technology and Society Studies, Grote Gracht 76, 6211 SZ,

Maastricht, The Netherlands; Tel: +31 43 38 82 566; Fax: +31 43 38 84 917 E-mail: [email protected]

immunisation programs will depend on the ability of these agencies to communicate effectively.

Can more effective benefit/risk communication support public trust in vaccination? And what should be the features of such communications? The article starts with a short review of key literature on risk communication and trust. Case studies developed by the author on MMR, Hepatitis B [5] and anti-HPV [14] vaccines are used to illustrate the importance of taking risk communication science on board. Concluding remarks highlight points that require urgent action.

WHAT IS RISK COMMUNICATION AND HOW DOES IT RELATE TO VACCINES?

The field of risk communication emerged from cognitive research in risk perception that showed that ‘lay’ concerns about hazards – from nuclear reactors [16-18] to chemical plants [19], radon [20], space [21, 22], and genetic engineering [23-25]– do not correspond with experts quantifications [26]. A series of factors critically affect perceptions, e.g. degree of control, catastrophic potential, and familiarity [27-29]. Rational decision-making is also clouded by ‘heuristics’ (mental shortcuts), bias and other emotions (e.g. “affect”) [30-32]. Research on risk communication has focused on making use of these cognitive insights to analyze and improve exchanges between senders and receivers [33] of risk messages (e.g. scientists, manufacturers, government officials, the media). Theories have been formalized to explain critical phenomena, such as the social amplification of risk by the media [34, 35], as well as the ups and downs of public trust [11, 36, 37].

Much has been written on risk from the perspectives of health psychology and sociology [38, 39]. Yet, there has been only limited discussion of pharmaceutical issues from the risk communication discipline [40]. A small number of studies, however, offer precious insights into vaccine perception and communication [41-46]. Research outcomes suggest that people are subject to relatively low overall

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10 Current Drug Safety, 2015, Vol. 10, No. 1 Frederic Bouder

concerns for vaccines when compared to dreaded non- medical (e.g. nuclear) or medical (e.g. DNA manipulation) activities [47-49]. Yet, many people are reluctant to accept vaccines when the prevalence of a disease is low [42]; on the other hand, safety concerns are heightened when vaccination is mandatory [30]. Key factors also contribute to anti- vaccine decision heuristics [41-43] such as compression (overestimating the frequency of rare risks and underestimating the frequency of common risks), availability (over-reporting of negative information by the media), omission bias (actions are perceived as more harmful than omission), risk ambiguity and freeloading (people rely on high vaccination rates and herd immunity to protect their unvaccinated child). These negative heuristics are sometimes counterbalanced by positive feelings, especially altruism. Altruistic feelings have led most parents to widely approve of vaccines being given to their children.

TRUST-BUILDING RISK COMMUNICATION

Over time, scientists and government experts have used three distinct communication strategies [49]:

(i) in its infancy risk communication has focused on conveying probabilistic thinking to the general public (...);

(ii) experts have then focused on persuasion and public relations to convince people that they should change their behavior (...);

(iii) in the third and last phase, the focus has been on developing a two-way communication process in which scientists, risk managers, and various laypersons engage in a social learning process”.

For most health and environmental risks, top-down persuasion has been shown to achieve compliance when public trust is high [11]. When regulators and industry do not enjoy high levels of public trust they may build confidence and credibility through “multiple messages about the nature of risk and other messages, not strictly about risk, that express concerns, opinions or reactions to risk messages or to legal or institutional arrangements” [21,50]. Yet, this approach is unlikely to change behavior without the help of targeted policy measures. For example, asking parents to consent to all teen vaccines increases consent for HPV vaccine above asking about just that vaccine [46].

Whether it is top-down or two-way, risk communication is more efficient when it is “proactive”. Proactive communication is significantly different from mere slogans. It takes place when institutions maintain multiple channels with influential stakeholders and avoid information vacuums [11]. A significant example is the Swedish Medical Product Agency’s handling of the H1N1 swine flu vaccine, where the Agency succeeded in combating rumors regarding the side effects of the vaccine, thus ensuring the highest take up rates of the vaccine worldwide.

LEARNING FROM VACCINE COMMUNICATION CASES

For expository purposes, we concentrate on five procedural principles – the so-called “five As” of public risk

communication- developed by the author for the UK Risk and Regulation Advisory Council [51]:

1- Assembling the evidence 2- Acknowledgement of public perspectives 3- Analysis of options 4- Authority in charge 5- Interacting with the audience The five principles are backed by 40+ years or so of research on risk communication combined with direct contributions from leading researchers in the field and senior practitioners. They may be described as a “survivor’s guide” designed to help and guide the actors themselves. The following section will illustrate how the communication of vaccine-related risk situations could greatly benefit from this input.

Assembling the Evidence

The first step for institutional communicators is to “assemble the evidence” about the risk. Concretely, this means that risk communicators need to demonstrate that they understand the risk and therefore have a credible basis for their decisions. During a vaccine safety alert there is not always enough time to collect and interpret the evidence, or to use risk jargon – it often takes time to establish the existence of a hazard, as well as estimate the magnitude and likelihood of harm. On 6 February 2009, two girls from the Spanish province of Valencia who had been vaccinated with the same batch of anti- Human Papillomavirus (HPV) vaccine Gardasil were admitted to a hospital. Immediate non-publicized discussions took place between the Spanish pharmaceutical regulator (AEMPS) and the manufacturer (Sanofi Pasteur). On 10 February, Sanofi Pasteur stopped the entire batch as a pre-emptive precautionary measure. The Spanish Ministry of Health immediately confirmed this precautionary measure [14]. Such prompt action illustrates the tendency that regulators have to err on the side of caution when they are confronted with an emergency situation.

Yet, swift action should not be an excuse for complacency. Regulators have often failed to re-appraise the precautionary measure after the crisis, even when reassuring evidence has been available. In the mid-1990s, the French Health Minister Mr. Douste-Blazy launched an ambitious vaccination campaign against Hepatitis B. In October 1998 when controversies started to develop about a possible link between the Hepatitis B vaccine and multiple sclerosis and lupus, on the basis of a number of studies [52-57], Mr. Bernard Kouchner, Mr. Douste-Balzy’s successor, suspended the school-based hepatitis B vaccination programs. The Government’s position was that the claim was at least credible. As a consequence, the large-scale French hepatitis B vaccination campaign was put on hold. At the time, the state of the science was in the regulator’s view, ‘unsettled’. They demanded that more studies should be conducted. However, French regulators did not revise their judgments when reassuring evidence was published and never resumed their large-scale immunisation efforts [5]. Assembling the evidence, however, is not only about paying attention to the quality of the evidence that is being

Risk Communication of Vaccines: Challenges in the Post-Trust Environment Current Drug Safety, 2015, Vol. 10, No. 1 11

presented at a certain point in time. It should be about engaging in an incremental process to generate, review and act on new evidence.

Assembling the evidence

Efficient risk communication requires demonstrating that your decisions are based on evidence

• What is the risk?

• Have you used the best available information to define the problem at stake?

• Are you aware of the chance that the hazard may occur?

• Are you aware of the size of the hazard?

• Who will benefit and who will suffer if the hazard occurs? Will everyone be equally affected?

• Have you considered complexity, ambiguity and uncertainty?

The institutional reaction to the now ‘textbook’ controversy about Measles Mumps and Rubella (MMR) [5] illustrates another problem: it takes very little to distort evidence in the eyes of the public. In 1998, a study led by anti-vaccine campaigner Dr. Andrew Wakefield was published in one of the leading scientific journals The Lancet. The paper indirectly suggested that the MMR vaccination might be responsible for cases of autism [58]. The media picked up the issue. Instead of stressing that the study challenged the scientific consensus, journalists – including the highly respected BBC- opted for a ‘balanced’ coverage where proponents and opponents would be given equal voice. They were slow to take on-board overwhelmin- gly reassuring evidence [59-64]. Regulators did not give credit to the Wakefield’s article. However, the nature of the reporting had the critical effect of undermining the science and scaring many parents.

Acknowledgement of Public Perspectives

Studying people’s views and concerns is central to an evidence-based approach to communication. For instance, knowing more about distinct patterns of vaccine perception would have helped scientists and decision makers devise communications to address unscientific claims about the MMR, hepatitis B and other vaccines. In the French Hepatitis B case, the controversy started with a series of articles that could be best described as evolving towards some sort of ‘conspiracy theory’ [5]. Opponents often expressed their views on the Internet. They consistently mixed the scientific issue with political considerations about the influence of the pharmaceutical industry on the government’s decision to promote large-scale vaccination. This was, arguably, one of the factors that contributed to a dramatic (negative) change in perception. The Health Ministry did not anticipate these developments, which led to a tougher reaction– i.e. a moratorium on the vaccination programme.

The understanding of public perceptions may have been used to judge the nature and seriousness of the negative perceptions among the public. Risk communicators need to get a better understanding of the views and concerns of those affected by the risk, whether as a sufferer or as a producer. When a controversy develops, it is often too late to generate

crucial data on risk perception. Too often, the tendency among experts has been to blame people’s irrationalities or the unpredictable nature of the crisis [65].

Typically, regulators tend to overestimate their capacity to convince people to take a specific course of action. And they underestimate the impact of contextual factors. For instance, how one is perceived is of critical importance. Acknowledging public perspectives should include an ongoing commitment to ‘test for trust’, i.e. understanding where people put their trust and why they consider some actors to be more trustworthy than others. The Gardasil scare was fuelled by negative views about the pharmaceutical industry. Opponents questioned the fairness of the vaccination process. They thought that the Industry had resorted to unethical and aggressive marketing campaigns to sell more vaccines. In addition, the immunisation programme was seen as expensive and a waste of public money – i.e. inefficient. Consumer groups and even some regulators highlighted that they considered Gardasil to be overpriced and therefore a strain on public finances [14].

The Gardasil controversy therefore illustrates particularly well that decision-makers would gain from paying more attention to the well-established determinants of public trust: efficiency, competence, and fairness are the three paramount variables of trust [11]. Those perceived as unfair and inefficient are less likely to be seen as trustworthy. Acting on these variables helps to formulate an effective risk communication that proactively addresses people’s concerns and (re)builds trust.

Acknowledgement of public perspectives

Efficient risk communication requires listening to individual and society’s views of the risk

• Do you understand how members of the public perceive the risk?

• Do you understand how influential risk actors view the risk?

• Have you identified the risk entrepreneurs that are likely to fear the risk the most?

• Have you identified those groups that are likely to want to amplify or diminish the risk, or others’ perceptions of the risk, for their own benefit?

• Have you considered those groups that are negatively affected by the risk, especially where those groups are seen as particularly vulnerable?

Analysis of Options

Vaccination campaigns are often launched on a grand scale, targeting millions of individuals. When worries emerge, precautionary measures may promptly replace vaccination commitments. In the French Hepatitis B and Spanish Gardasil cases policy makers concentrated on demonstrating that the government was tough and that they would enforce the ‘better safe than sorry’ precautionary principle. They failed to acknowledge alternative measures and did not communicate the downside of precaution [66]. The communications of the European Medicines Agency were ambiguous, stressing at the same time the absence of any causal relationship between the vaccine and the cases, the need for precautionary measures as well as further investigation to establish the links between the case and the vaccine. The EMA even required that product labels be

12 Current Drug Safety, 2015, Vol. 10, No. 1 Frederic Bouder

modified to cover the risk of syncope, which was interpreted by some observers as evidence that the public should worry [14].

Hastily devised precautions can undermine public confidence in the risk assessment process and, ultimately, challenges immunisation. Indefectible commitments to keep immunisation programs on course may prove equally problematic when the pros and cons of business as usual vs. contingency measures remain obscure. The UK government has always offered strong support for MMR vaccination; yet it has sometimes used scare tactics and persuasion, a strategy that is likely to fail [67, 68]. Engaging with lay audiences and trusted parties in a reasoned discussion about the pros and cons of triple jabs vaccines versus single jab vaccines would have worked better.

In a nutshell, the quality of risk communications will benefit from openly discussing the broad range of options and the associated trade-offs that drive immunisation policies. Crucially, this implies for institutional actors to devise a clear communication of the expected impacts, costs and benefits of action as well as inaction. Too often, however, the cost/benefit assessment that underpins vital decisions remains a matter for experts with little outside input.

Analysis of options

Efficient risk communication requires balancing options and to be open about it

• Can you demonstrate that you have weighed the costs and benefits of the risk and the options for managing it?

• Do you have good arguments for assigning the necessary trade-offs between conflicting objectives and goals?

• Are you clear about the impact of doing too much, too little or nothing?

• When time permits, do you look for a range of options and select the one that promises the best balance of ‘upsides’ and ‘downsides’?

• When you have the opportunity, do you reduce those risks that are easy and inexpensive to reduce?

Authority in Charge

Risk communicators need to define the nature of their involvement with the risk. Who should speak? Who is listened to? For example do governments and industries always need to lead the communication process? For vaccine manufacturers (so-called “risk producers”) and regulators silence is not an option [11]. In many cases, however, those who have a direct stake in the issue will benefit from stepping back and allowing neutral trusted parties to lead. In 2009 Spanish authorities successfully launched an ad hoc expert committee to investigate and report on possible side effects of Gardasil. The committee members were renowned medical experts from a range of medical disciplines (immunology etc.). The committee visited the hospital where the two girls were diagnosed with status epilepticus. They conducted a thorough inquiry that found no trace of a biological link between the vaccine and those cases. On 9 April 2009, these results were communicated to the Ministry of Health. A reassuring summary report explaining the Public Health aspects of the issue was published, made available on the internet and communicated to journalists.

After the release of the conclusions of the investigation committee, the media controversy ceased overnight, while the Internet controversy faded away soon after [14].

Authority in charge

Effective risk communication requires thoroughly defining the nature of your involvement

• What are the reasons for your organization to step in?

• Have you identified conflicting views within your organization?

• Have you made sufficient efforts to ensure that your organization speaks with one voice?

• Do you periodically check how well-trusted you are?

• Should any other public body be speaking out on this issue?

• Have you identified independent third parties that are more trusted than you and may facilitate the public debate?

Interacting with the Audience

Even though they may otherwise blame the public’s ‘irrationalities’, ill-advised policy makers too often focus their communications on emotions. For instance, the response to the MMR vaccine scares has largely evolved towards emotion-based communication. Policy makers have suggested that parents who refuse immunisation are putting their children at risk [5]. Yet, in the initial phase of the public debate, many parents were not opposed to the vaccination, but were just unsure about the safety of the MMR triple jab. Playing the emotional card did not help them understand why they could not have access to three separate jabs against Measles, Mumps and Rubella. It only suggested that the government intended to push for vaccination at any cost. If anything, the institutional approach showed that attitudes that are perceived as patronising only make compliance worse.

Traditional media outlets (such as newspapers and television) have been, and are still central communication vehicles [34, 35]. Yet the Internet has become an increasingly important factor, including as a risk amplifier [14] and propagator of unscientific rumors [12, 13]. The impact of the Internet in the reinforcement and propagation of negative perceptions of vaccines – insofar as it has the ability to act as an unreliable source of information, to spread quack science and rumors and to amplify risks – is generating perplexity among those concerned with designing and implementing effective health programs. In the case of the Hepatitis B scandal in France, reassuring news reports did not prevent the propagation of internet-based conspiracy theories [5].

Nevertheless, such pessimistic portraits of the deleterious effects of the Internet are only one side of the story. For public-health authorities and agencies, the Internet is also a formidable, yet underused, instrument for the communicating benefits and risks. For example, all regulatory agencies maintain websites. How effective is their use of this technology? Do agencies do a good job of using the web to prevent the amplification of negative perceptions? Is it likely that the current approach, which often focuses on disclosure and the release of raw data [69-71], will be insufficient to ensure an effective communication of benefits and risks. Our analysis of FDA [70] and European [71]

Risk Communication of Vaccines: Challenges in the Post-Trust Environment Current Drug Safety, 2015, Vol. 10, No. 1 13

practices finds that transparency initiatives are often confusing for patients and that proactive communication is much needed.

Audience to interact with

Effective risk communication requires interacting with the right audience using the right methods

• Have you clarified who the audience of your message is likely to be?

• Have you clarified how you will interact with other groups (through information, consultation, and deliberation)?

• Are you clear whether messages are intended to inform your organization, organized groups or the general public?

• Have you used communication methods that have worked in similar circumstances?

• Do you select and train effective communicators and learn from examples of similar situations where messages have proven successful?

CONCLUSION

Careful analyses of institutional communications highlight practices that need to be tackled urgently:

- Communications are often one-way rather than two- way. Regulatory agencies use web portals as their primary instrument to reach outside audiences. Too often this leads to data dumping (so-called ‘fishbowl transparency’) or one-size-fits-all communications (‘press releases’) that confuse patients and are not sufficient to build trust [69-71].

- Against the advice of risk theorists, persuasion remains the agencies’ main goal. Communications often seek to educate the public about the agency’s view, rather than to engage in a two-way communication process.

- In contrast to the recommendations of risk theories, the current risk-communication approach does not typically balance benefits and risks. In the event of a vaccine (or drug) alert, the regulator’s discourse focuses on the risks. As a consequence, the content of the communications tends to be excessively risk- averse.

One important lesson is that agencies have been able to build trust through direct or delegated interactions (e.g. an expert committee to investigate the issue). The FDA’s and EMA’s commitment towards more transparency is likely to increase rather than diminish the role of the Internet as the instrument of choice for the release of information about benefits and risks. Yet merely providing information without paying attention to perceptions does not constitute successful communication. Trust in immunisation programs requires effective risk-communication methods. In conclusion, risk- communication studies recommend a number of simple steps towards achieving critical improvements that agencies may consider:

1- Always test for trust before selecting a communication approach.

2- Think of new technologies – especially the Internet and the new media - as tools among many. The

crucial role of interpersonal relationships – with patients and with those who object to becoming patients – should not be underestimated.

3- In recent years, European regulators, including the EMA, have made their websites more user-friendly. However, the conduct of effective risk communication on the web requires engaging in more interactive uses of Internet technology. Seek solutions that foster exchanges of information, feedback, and reasoned discussion of the science. The websites of conventional media, such as that of the BBC science pages for example, have already engaged in this kind of process.

More science is clearly needed. External risk communication advisory boards, composed of experts from the risk communication and medical fields would help integrate risk communication research into everyday practice.

CONFLICT OF INTEREST

The author confirms that this article content has no conflict of interest.

ACKNOWLEDGEMENTS

The author would like to thank the UK Government Office for Science and the Economic and Social Research Council which funded the “Practical Guide to Public Risk Communication”. The author is also grateful for the support received from the European Medicines Agencies who funded an evaluation of the Gardasil case. The author would also like to thank leading scholars, especially Prof. Ragnar Löfstedt, Prof. Baruch Fischhoff and Prof. Ortwin Renn for their ongoing support and advice.

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Received: March 14, 2014 Revised: May 6, 2014 Accepted: May 28, 2014