Chapter 3: Vaccine Opposition and Hesitancy

INTRODUCTION

Vaccines are among the greatest public health achievements of the twentieth century, drastically reducing morbidity and mortality from preventable diseases. However, vaccine opposition and hesitancy have persisted since Edward Jenner's first smallpox vaccine in the eighteenth century. The World Health Organization ranked vaccine hesitancy as a top public health threat in 2019 due to a crisis of confidence fueled by social, cultural, and communication changes. This includes distrust in vaccines, healthcare providers (HCPs), governments, and institutions.

Roots of vaccine hesitancy vary globally: pseudoscience (e.g., MMR-autism myth), real safety concerns (e.g., Pandemrix and narcolepsy), health system failures, and rejection of mainstream medicine in some communities. Consequences include decreased vaccine uptake, increased outbreaks, and epidemics. Physicians are key to addressing this crisis through strong vaccine recommendations.

VACCINE COVERAGE AND OUTBREAKS

North America

Herd immunity requires high vaccination coverage (93–95% for measles). Despite relatively high coverage in the US and Canada, measles outbreaks have occurred due to clusters of unvaccinated or under-vaccinated individuals. Outbreaks often begin with unvaccinated travelers importing disease into communities with low vaccination rates.

Outside North America

Vaccine coverage is lower in some countries (e.g., Samoa 31%, Philippines 67%), increasing risk for travelers and immunocompromised individuals.

FACTORS IN VACCINE HESITANCY

Vaccine hesitancy is distinct from vaccination coverage rates. WHO defines hesitancy as delay or refusal despite availability. Vaccine acceptance exists on a continuum from active demand to outright refusal. Hesitancy is influenced by:

Complacency: Low perceived risk of disease, prioritizing other concerns, influenced by misinformation.
Convenience: Access, affordability, cultural safety, language barriers.
Confidence: Trust in vaccine safety, healthcare system, and authorities.

Individualized Health Care: Shift to patient-tailored care conflicts with public health’s community focus.
Parenting Trends: "Good parents" viewed as critical consumers, seeking personalized advice, sometimes conflicting with public health schedules.
Traditional Media: Historically gave false equivalence to anti-vaccine claims, amplifying misinformation.
Internet & Social Media: Create echo chambers reinforcing beliefs; spread misinformation and disinformation widely. Efforts by social media companies to limit misinformation have had mixed effects.
Grassroots Support: Groups like Shots Heard Round the World support pro-vaccine messaging.

APPROACH TO THE PATIENT

Effective vaccine hesitancy intervention is dialogue-based, multicomponent, and tailored. Challenges include:

Provider discomfort or lack of training.
Importance of strong, clear vaccine recommendations.
Tailored communication based on patient attitude.
Transparency about benefits and risks.
Provision of reliable information sources.
Revisit and reinforce recommendations during follow-ups.

Communication style:

Presumptive/directive approach generally yields higher uptake.
Participatory/guiding approach suits more hesitant individuals.

OTHER CONSIDERATIONS DURING CLINICAL ENCOUNTERS

Missed Opportunities: Many under-vaccinated individuals could be vaccinated if all opportunities were taken.
Vaccination should be integrated into all healthcare encounters.
Providers should make preemptive vaccine recommendations and ensure follow-up.
Adverse Events: Must be reported and followed up.
Inequities: Socially disadvantaged populations face greater under-vaccination and disease risk.
Vaccine refusal: Should be documented and approached with ongoing dialogue.

CONCLUSION

Vaccine hesitancy is complex and variable. HCPs should build skills and confidence to make strong vaccine recommendations.

FOCUS: COVID-19 VACCINE HESITANCY

COVID-19 vaccines raise familiar and novel concerns about newness, safety, and politicization. Providers must educate themselves on:

Vaccine development speed and safety monitoring.
New vaccine platforms (mRNA, viral vector).
Gaps in trial data for certain populations.
Historic and ongoing distrust in marginalized communities.
Strategies for effective patient communication.