Vaccines in the public eye

Refusal of vaccines by parents due to social media, Dunning-Kruger effects and epistemic self-reliance; a new kind of cheater?

Modern day vaccine design faces more challenges than just scientific ones215. It is clear that prevention far outweighs treatment of the disease, both in terms of monetary costs and human suffering216,217. The economic burden of vaccine-preventable diseases in the US was estimated at $9 billion per year218. These are costs associated with diseases for which a vaccine is available, so almost 80 percent of these costs are due to unvaccinated invididuals218. The financial costs of epidemics for which there are currently no vaccines are enormous. For example, the financial losses of airline companies during the global SARS epidemic was over $7 billion, while the global reduction in GDP was $33 billion219. The SARS epidemic lasted a year and was fatal to 916 people, scaling it as a relatively small global health crisis. In comparison, the 1918-19 Spanish flu would (by estimation) reduce the world’s current economic output by almost 5% and cost more than $3 trillion219. To put these costs in perspective, it was recently estimated that the costs for progressing at least one vaccine through to the end of phase 2a for each of the major 11 epidemic infectious diseases[1] would cost a minimum of $2,8-3,7 billion per disease220. Both people and pathogen vectors (like malaria mosquitoes) transverse national borders221–224, making pandemics a world-wide problem. Indeed, global vaccine-development funds have been proposed, but remain difficult due to different risk assessments, governmental prioritization or a lack of incentive because the market is considered too small225. While these cost-benefit comparisons are difficult to completely objectify and weigh, it is clear prevention far outweighs the costs of treatment, even in the case human suffering does not offer sufficient justification.

Nonetheless, a growing group of parents refuse to vaccinate their children, a phenomenon known as “vaccine hesitancy”. Since unvaccinated individuals put communities risk of disease226, interventions for reducing parental vaccine hesitancy are critically needed227. In fact, understanding vaccine hesitancy has become an international priority, as the World Health Organization outlined in the global vaccine action plan 2011-2020228. Vaccine hesitancy is largely defined as the “delay in acceptance or refusal of vaccination despite availability of vaccination services”229. It is a highly complex phenomenon but was modeled by the “Three Cs”; Confidence, Complacency and Convenience229. Confidence is defined as the trust in the therapeutic efficacy of vaccines, the health system (physicians, pharmaceutical companies etc) and the motivation of policy-makers on vaccination programs. Complacency is the lack of perceived risk of vaccine-preventable diseases and lack of personal and societal health responsibilities. Convenience is the physical/geographical availability, affordability, ability to understand and the appeal of vaccines. While the factors influencing the three Cs is far beyond the scope of this thesis230–232, several notable influences are becoming increasingly important to “vaccine hesitancy” in the Western world.

The arguments discussed inward are only part of the debate surrounding “vaccine hesitance” and excludes important influences like religious, geographic and socioeconomic differences229,232. Also, vaccine hesitance is not a problem from the last decade per se280, but with the advent of technology, widespread accessibility of information and increased individualism/entitlement, the paradigm has shifted and will require continuous attention. Vaccine design is ultimately futile if trust in the science is lost.

[1]Crimean Congo hemorrhagic fever, chikungunya, Ebola, Lassa, Marburg, Middle East respiratory syndrome coronavirus, Nipah, Rift Valley fever, severe acute respiratory syndrome, severe fever with thrombocytopenia syndrome, and Zika.