When I sat down in early 2016 to begin writing a book about the history of vaccines, I realized that anti-vaccine movements always seemed to accompany each new scientific breakthrough. Indeed, an infectious disease colleague of mine managed, for a time at least, to convince me to not discuss this link. He argued that anti-vaccine sentiments had long since evaporated with the exposure that charlatans, such as Andrew Wakefield, had falsified data and were motivated solely by greed. Yet, I returned to the project on November 9, 2016, motivated by the fact that the United States had just elected its first anti-vaccine president.

Fast-forward a half decade and we find ourselves again confronting a substantial threat from the anti-vaccine movement.  A failure to achieve “herd immunity,” a scientific term reflecting whether a susceptible individual is likely to encounter an infectious spreader, could allow the ongoing pandemic to become perpetually endemic, ensuring inevitable future spikes in infections from new mutations and warranting a continued development of newer vaccines and therapeutics to counter these variants.

This concern raises many questions, but also opportunities.

The first and fundamental question centers upon why vaccines seem to elicit such powerful emotions. The answer, gleaned from researching the introduction of new vaccines for more than two centuries, seems to be that vaccines are administered to prevent a disease that the recipient may (or may not) encounter in the future. Stated another way, a patient will readily accept a risk of potential side-effects to alleviate a pre-existing disease. Yet the concept that one might encounter even short-term symptoms amidst preventing the possibility of future suffering proves to be a bridge too far for some.

Compounding this problem, many of us have largely forgotten the devastation wrought by invisible microbes – preferring to rationalize that past generations had conquered infectious diseases with the discovery of penicillin and other wonder cures (including ironically, vaccines). Presumably, the ongoing pandemic has placed such “objective” assumptions into proper perspective.

This presumption of an objective rationale is often betrayed by a closer look at anti-vaccine movements. The reasons for rejecting a vaccine have ranged from occasionally reasonable to the utterly absurd.  At one end of the spectrum, the first vaccine was a form of cowpox virus that protected against smallpox, one of the largest serial killers of our species ever to exist. Indeed, the word “vaccine,” from the Latin word for cow, vacca, reflects its bovine origin.  Yet early attempts to vaccinate the public in the 19th century were resisted with a presumption that a cow virus would cause vaccinated individuals to sprout horns and rampage like minotaurs.

Nearly as absurd was the response to a far more contemporary vaccine, that targeting human papillomavirus (HPV). This vaccine has the potential to prevent thousands of deaths from cervical, rectal, and head and neck cancers. HPV is often miscategorized as a sexually transmitted disease (the virus resides on the body from mid-thigh to just below the beltline and thus can be communicated even without direct sexual contact). Thus, many conservatives opposed the HPV vaccine based upon an argument that vaccination would cause innocent children, who might not have otherwise entertain such ideas, to initiate their own forms of rampage, this time sexual. Yet, the statistics do not indicate that HPV-vaccinated teenagers have partaken in a decadent frenzy just as cowpox-vaccinated individuals did not sprout horns or a tail.

Far more rational were legitimate concerns arising from the fact that part of the early rollout of the polio vaccine were marred by a manufacturing mistake in the 1950s. Known as the Cutter Incident, thousands of children in California were unknowingly injected with a dangerous virus; some died and others were left paralyzed. This situation was soon rectified, and public trust in vaccines soon regained; effectively eliminating polio as a threat to most nations today.

A similar concern seems to surround the COVID vaccines. In this case, the rationale is that the vaccines were simply developed too quickly (and must therefore be problematic). Although it is certainly the case that these vaccines were developed in record time, this justification for hesitance is not supported by findings from hundreds of millions of people, who have been vaccinated around the world.

Looking back at 2020, it seems paradoxical to state that we got lucky, arguably one of the few times that the odds favored humanity in that annus horribilis. The vaccines, which resulted from a focused and unparalleled cooperation amongst both the public and private sectors, have proven to be both amazingly efficacious and remarkably safe. Apart from a handful of high-profile exceptions (which are disproportionately captured by the headlines), the safety of the vaccines have exceeded all expectations.

The key to a brighter future is that we all must engage constructively with vaccine skeptics. These are generally not utterly irrational actors, but scared individuals. Their fears are generally well-intended, but like prior generations concerned by rampaging minotaurs or teenagers, are not based upon objective analyses of the data. The mission that each of us should undertake is to learn the facts about these vaccines from reputable sources such as the Canadian Public Health Agency or the American Centers for Disease Control and Prevention. We can then convey these to our friends, neighbors and family members, who might have reservations about being vaccinated. Engaged conversations, not lectures, will undoubtedly yield positive results. Only through such constructive engagement can we reach herd immunity, not merely at the local level, but internationally.

Looking ahead, we must also recognize that pandemics are surprisingly common, arising every few decades. Historically, most pandemics arise from new and deadly influenza variants, the most famous being the Spanish Influenza outbreak just over a century ago. As I pointed out in A Prescription for Change, there is a direct causation linking the Spanish flu to the biotechnology revolution that began four decades later. It seems somehow fitting that the legacy of the Spanish flu provided the foundations for the mRNA and adenovirus vaccine technologies that are proving so effective today.

Yet, the same experiences and technologies that promise to end the COVID-19 pandemic (e.g., mRNA or adenovirus-based vaccines) might come full circle and prevent a recurrence of a future Spanish influenza. These same technologies might provide an opportunity to develop so-called “universal influenza vaccines” with the ability to protect against all forms of the virus. The elimination of this threat could save countless lives and allow the ongoing pandemic to be viewed by future generations as the legacy left behind by COVID-19 and thus mark the beginning of a new era of improved public health.