Although vaccines are recognized as one of the greatest public health achievements of the last century and save millions of lives each year, vaccination programs are fighting to maintain public confidence. Public confidence in vaccines is decreasing for various reasons and antivaccine movements are becoming stronger.1–3 Individual decision-making regarding vaccination is not based only on knowledge deficit of vaccine-hesitant individuals but on more complex determinants that may involve emotional, cultural and social factors.4 “The days when health officials could issue advice, based on the very best medical and scientific data, and expect populations to comply, may be fading” (Margaret Chan, World Health Organization Director-General, 2010).5 Use of technologies such as smartphones, social networks and the Internet has changed the way we communicated and provides innovative ways to monitor trends that concern people. Together, these advancements are leading to a convergence of people, information, technology and communities to improve health outcomes in a modern hyperconnected world.
On May 13, 2015, in Leipzig, Germany, the Global Medical Affairs team of GSK Vaccines organized a satellite symposium at the European Society of Paediatric Infectious Disease (ESPID) conference, and we were invited as experts to discuss how to maintain and increase vaccine acceptance and coverage for all age groups in the digital era. The symposium was structured around a series of presentations by ourselves as members of a multidisciplinary panel (consisting of an anthropologist, a public health policy advisor, a vaccine industry expert, a health care journalist and a practicing physician) and was followed by discussions with delegates at the symposium and a live global webinar audience. Transcripts of the symposium, including video recordings of public perceptions captured by interviews conducted in London, Paris and Berlin in April 2015 formed the basis of the needs analysis for vaccination “to go viral”.
The purpose of this article is to delineate the presentations and findings that emerged from the meeting with the goal of highlighting proactive measures for building, maintaining and enhancing trust in vaccination through innovative communication and evidence-based interaction with the end user.
OUT OF SIGHT, OUT OF MIND
Vaccination has become a victim of its own success with the resultant significant decrease in vaccine-preventable infections contributing to vaccine complacency.6 The current low global incidence of diseases such as tetanus, diphtheria and polio has led to the misperception by some that vaccination is no longer necessary and that vaccine-associated risk may outweigh that of the disease itself. These people may thus prefer to avoid vaccination. One of the prevalent concerns about vaccines is safety.7 Vaccines, like all medicines, can have adverse events however, but because vaccines are given to healthy people, notably most infants and children, people expect and demand higher safety standard than for drugs. Most vaccine-related adverse events are mild or moderate, such as reactions at the site of injection (pain, redness and swelling) or fever, but sometimes, severe adverse events can occur, such as anaphylactic reactions or febrile seizures.8 All vaccines are tested in clinical trials during the development phase and their safety and benefit–risk profiles are continuously monitored and reevaluated by the manufacturers and health authorities, after licensure for their entire duration of use.2 However, most health care professionals (HCPs) and the public are not aware of this rigorous and continuous safety assessment of vaccines. Therefore, the general public needs to be made aware of the robust safety systems, and that they themselves can report concerns as well as HCPs giving immunizations. If potential concerns arise, a transparent approach is essential to enhance and maintain public trust.
Vaccine-hesitant individuals may refuse or delay vaccination for themselves or their children. This leads to pockets of unprotected population and increases the risk of disease outbreaks if vaccine coverage decreases locally below the herd immunity threshold. Herd immunity is especially important because it provides indirect protection for those who are not yet or cannot be vaccinated, such as newborns and immunocompromised individuals.9 Recent measles outbreaks in the United States and Europe, in which more than 31,000 cases were reported in 2013,10 notably resulted from insufficient vaccination rates.11–13
As illustrated by the street interviews of people in 3 European capitals presented at the symposium (Fig. 1), the continuum of public opinion ranges from pro- to antivaccine attitudes.4,14 In a literature review, 5 categories of parents were identified.15 At one end are pro-vaccine people who do not question the value of vaccines (30%–40% of the population) and those who have only minor concerns (25%–35%). Then, there are hesitant people who have significant concerns but still vaccinate their children (20%–30%), followed by those who question vaccines and may delay 1 or 2 recommended vaccines, or who may not vaccinate against certain diseases (2%–27%). Finally, a few people refuse all vaccines (<2% of the population).15
Vaccine confidence implies trust in the concept of prevention through vaccination, the vaccine product and manufacturers, the policy-makers responsible for national vaccine programs and the HCPs who administer the vaccines. The HCPs play a critical role in the vaccine confidence landscape. On one hand, they exert the strongest influence on parents regarding vaccination decisions, yet, on the other hand, they are themselves increasingly reported to be vaccine hesitant about 1 or more vaccines.5
HEALTH IN THE DIGITAL ERA
An increasing number of people use the Internet to find information about health, including vaccination.16 A survey conducted in the United States in 2013 showed that 59% of the adults and 72% of the Internet users had searched online for health information within the previous year.17 In the industrialized world, a third of mobile phone owners look at health information via their phones and a fifth of smartphone owners have downloaded a health application, mostly about exercise, diet or weight.18 It was forecasted that 500 million people would be using mobile health applications by the end of 2015.19 However, most applications that claim to deal with health are not evidence-based.20–22
As an example, in Canada in 2015, television was still the primary source of health information but the proportion of persons who rely on the Internet for health information increased by 11% from 2007 to 2015 (from 32% to 43%) and was much higher in young adults (64% for 18- to 34-year-olds in 2015).23 In addition, approximately 80% of these persons changed at least 1 behavior as a consequence of this health information.23 A survey of 5648 persons in 6 European countries (Great Britain, Sweden, the Netherlands, Spain, Germany and France) showed that, despite being considered a relatively untrustworthy resource, the Internet was still the third most popular source of health information, after general practitioners and pharmacists.24 The rate may vary by country; however, it shows an overall trend that is worth consideration.
With the development of social media such as Facebook, Twitter and personal blogs, communication has been made easier and border-free. Compared with traditional communication channels, information and misinformation can be shared between people without the intervention of educated professionals.16 Perceptions on vaccine risk can now travel globally and spread virally. This raises the possibility that any gaps in the information provided by vaccine manufacturers, HCPs or health authorities may be filled by unverified sources. In addition, social media can act as an “echo chamber,” by which people find their own negative opinions confirmed in the rumors, misinformation and personal opinions disseminated by others. This can reinforce individual beliefs whether the information is supported by scientific evidence.25
Larson et al26 created an online information media surveillance system to detect emerging global public concerns about vaccines. They analyzed data from 10,380 media reports obtained between May 2011 and April 2012 from 144 countries. Approximately 69% of these reports contained positive or neutral content about vaccines and 31% contained negative content. Of the latter, 24% were associated with impacts on vaccine programs and disease outbreaks; 21% with beliefs, awareness and perceptions about vaccines; and 16% each with vaccine safety and vaccine delivery programs (Fig. 2). These data show that the nature of public concerns about vaccines is complex and highly diverse and that, though concerns about vaccines vary geographically, global dissemination of some concerns has occurred and been enhanced by Internet-based communication.27–29
THE “UMBRELLA APPROACH” TO PROTECTION
Our collective view is that the vaccination paradigm needs to shift from vaccination with a childhood connotation to an “umbrella approach” of protection for the whole family, with the goal of improving health and reducing morbidity in all age groups.30 Indeed, vaccination programs are not limited to young children but also include all other age categories, such as adolescents (eg, human papillomavirus, meningitis), adults and older adults (eg, influenza, diphtheria, tetanus, pertussis, Streptococcus pneumoniae) and travelers (eg, hepatitis A, yellow fever).31 At all ages, every consultation with an HCP could thus be used as an opportunity to raise the issue of disease prevention, including vaccination, which should have a central role in healthy living, along with other measures such as a healthy diet and exercise. An important aspect is that physicians’ attitudes and the language they use heavily influence whether parents decide to vaccinate their children.32 Opel et al32 found that parents in the United States were more likely to accept vaccination for their child if the vaccine provider used a presumptive (eg, “Well, we have to do some shots”) rather than a participatory (eg, “What do you want to do about shots?”) format to initiate the vaccine recommendation (74% vs. 4% accepted).
HOW CAN TRUST BE ENHANCED?
It has been stated that “trust takes years to build, seconds to break, and forever to rebuild.” This may also apply to vaccines. One of the most famous vaccination controversies started with an article from Andrew Wakefield et al in The Lancet in 1998 suggesting an association between the mumps, measles and rubella vaccine and autism in children.33 This concern was greatly amplified by the media.34 This article was eventually retracted after being deemed fraudulent35,36 but, more than 15 years later and despite the numerous studies that have failed to show a link between the mumps, measles and rubella vaccine and autism,37 some parents continue to harbor skepticism about this vaccine and coverage remains suboptimal in some regions or counties in several countries, including the United Kingdom, France and the United States.38–41 The amplification of concern by the media illustrates its pervasive impact on public perceptions of risk and that “strong beliefs about risk, once formed, change very slowly and are extraordinarily persistent in the face of contrary evidence.”42 We recommend that HCPs listen to their patients, take time to answer their questions and understand their concerns, and adapt their communication to each individual and follow-up on the decision at a later stage.
We are aware that the lack of trust in the vaccine manufacturers, and in the pharmaceutical industry in general, is linked to the fact that they make profits from selling vaccines. People may perceive that vaccine industry employees, including the scientists who develop the vaccines, have a vested interest in highlighting the benefits of vaccines and hiding their risks.2 Similarly, people may consider that, for financial reasons, vaccine manufacturers inappropriately influence health authorities to recommend and physicians to administer vaccines. For these reasons, all industry and vaccination stakeholders should examine their own behavior according to an approved code of conduct/ethics. However, words captured in such codes can only come to life through actions and behaviors.2,43 Authorities and pharmaceutical companies thus decided to disclose payments to HCPs who provide consultancy to the companies.44–48 In addition, one of the major vaccine manufacturers, GSK Vaccines, announced in 2013 major changes in the way they will engage with HCPs as from 2016 (eg, end direct payments to HCPs for speaking about their products and transfer decisions about sponsorship for attendance at medical conferences to independent third parties).49
We consider transparency to be crucial at every stage of research and communication: in assessing the burdens of disease, in determining the efficacy and safety of vaccines, in the decision-making processes for vaccination policies and in safety surveillance after licensure.2 To facilitate transparency, several pharmaceutical companies, including major vaccine manufacturers, have established a platform for external scientists (https://ClinicalStudyDataRequest.com) to access clinical trial data and provide opportunities to conduct further research that may help advance science or improve patient care. We believe that a multistakeholder approach that includes public–private partnerships to build trust in vaccines is highly relevant. Informed, accurate, understandable, appropriate and trusted communication is also needed, but communicating such knowledge alone is not the panacea for behavioral change.50 The process is a complex one that entails cultural factors, attitudes, motivations, experiences, information needs, social norms and structural barriers. It is therefore important that health communication research identifies effective communication interventions and tailored approaches.50
HEALTH COMMUNICATION IN THE DIGITAL ERA
In the age of the Internet and mass communication, power has shifted from doctors to their patients.51 People have now become central actors of their own health and need to be recognized and informed as such. When individuals turn to the Internet for vaccination advice, antivaccine websites can influence their decision to vaccinate. Most of these websites use narratives to increase the perceived risk of adverse events. Such narratives describing negative experiences with adverse events after vaccination are easy to understand and highly emotional.16,52 By contrast, the current tools used by the medical community and public health authorities include evidence-based information such as statistics or research, which are more difficult to communicate and understand. Such approaches may not be sufficient to convince vaccine-hesitant people. Storytelling strategies, such as those used by the antivaccine movements (ie, providing positive narratives about vaccination), combined with evidence-based information, could allow a much stronger response against the antivaccine arguments.25 A recent Canadian initiative, supported by UNICEF, is an example of promoting positive vaccination conversation by HCPs through an interactive website by posting articles and stories on social media “to gain points” with the aim and motto of “act locally, vaccinate globally.”53
From our perspective, the medical community needs to seriously address concerns about the value of vaccination, both at the individual and societal levels, by introducing scientific evidence in the context of trustful parent–physician relationships. Policy-makers should invest more in proactive communication strategies to disseminate the results in an understandable way.24,54 Investing in regular and continuous positive communication on the role and value of vaccines when infectious diseases are under control will combat vaccine complacency and avoid communicating about vaccines only when safety issues or outbreaks arise.2 The typical life cycle of vaccination programs has been illustrated by the US Centers for Disease Control and Prevention (Fig. 3).55,56 Because coverage and vaccine efficacy are never 100%, some individuals will always remain susceptible to a disease. When the number of susceptible individuals reaches a critical point, for instance, following the discovery of a safety issue or because of access issues, new outbreaks may arise many years after the disease had apparently disappeared.55,56 Evidence-based information is thus needed before reaching this critical point. Since 2005, the European Immunization Week campaign, coordinated by the World Health Organization regional office for Europe, offers the perfect opportunity for countries and regions to attach proactive and reactive local initiatives and communication activities about vaccines and vaccination programs.57
In addition to universal communication, tailored communication (ie, adapted to different populations) is needed. For instance, messages for adolescents and young adults are more beneficial if provided through the Internet and social media, whereas messages for people who are older than 55 are more effective if they are televised or in newspapers.23 In 2013, the World Health Organization published a guide for tailoring immunization programs in the European region.58,59 This guide provides tools to identify susceptible populations, determine demand- and supply-side barriers to vaccination and implement evidence-based interventions. These strategies may be used at any time to maintain high coverage rates but may be particularly valuable for areas having low vaccination coverage or for populations who are highly susceptible to vaccine-preventable diseases. Tailored programs have been successfully implemented in more than 5 countries so far and have resulted in improved health care access for migrants in Sweden and Roma populations in Bulgaria, and have identified barriers to vaccination among the ultraorthodox Jewish communities in Greater London.59,60
Because all HCPs have a role in vaccination, courses on immunology and vaccinology should be incorporated (if not already) into the medical curriculum of physicians, pharmacists, midwives and nurses. As an example, seasonal influenza vaccination is recommended for HCPs but vaccination uptake is often low.61 Various interventions, including education, have been explored to increase this uptake, though benefits of these interventions remain variable.62,63 Similarly, efforts should be made to reinforce appropriate medical exposure and research orientation for journalists so that they can provide the public with accurate information.
Children could also be educated at school about vaccination and vaccines so that future generations may better understand the benefits of vaccination for a healthy living for both themselves and the society in general. Besides educating people on the safety and efficacy of vaccines, it is also important to educate them about the severity of the diseases and the risks of not getting vaccinated, especially when such diseases are rare as a result of vaccination. This could be accomplished as it is currently for healthy diet, exercise, alcohol, drugs or sexual behavior education programs.
Research in cognitive psychology has shown that people are more likely to remember “sticky myths” than their corrections because revising preexisting beliefs in light of new facts demands more cognitive efforts.64 Highlighting the degree of medical consensus increases perceived scientific agreement, which acts as a consequential gateway belief by promoting favorable public attitudes toward vaccination.65
RECOMMENDATIONS FOR VACCINATION TO “GO VIRAL”
Although public confidence is a linchpin of successful vaccination programs, we believe that a collective approach will be essential to help build and maintain confidence in vaccines and vaccination programs and, therefore, to reach and sustain the vaccination coverage required to eliminate vaccine-preventable diseases. This approach should involve the pharmaceutical industry, policy-makers and HCPs with the help of anthropological and social sciences and health media communication. We have listed the contributions of each stakeholder in Table 1, that we consider essential to increase confidence in vaccination in the digital age.
Converting the results of vaccine research into successful vaccination programs, and replacing misinformation with evidence-based communication, will require a multidisciplinary, cohesive, targeted and managed approach that embraces Internet-based applications and smartphone technology to reach out to all populations. The vaccine community needs to be aware that the current contextual dynamics of the Internet and social media could impact the delivery and acceptance of vaccination programs in the digital age. With the help of anthropological and social sciences and health media communication, we consider that it is time for the industry, policy-makers and HCPs to embrace the digital age of communication and for vaccination “to go viral.”
The authors thank Drs. Volker Vetter and Alberta Di Pasquale (GSK Vaccines, Belgium) for their critical review of the manuscript. Authors also acknowledge the support of Dr. Alberta Di Pasquale and the Global Medical Affairs Vaccine Science, Adjuvants Technology and Medical Education team (GSK Vaccines, Belgium) and the ESPID governing body for organizing the satellite symposium. Writing assistance was provided by Dr. Julie Harriague (4Clinics, France). Editorial assistance and manuscript coordination were provided by Carole Desiron (Business & Decision Life Sciences for GSK Vaccines, Belgium).
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