Editor’s Note: This piece is by physician and Critica contributor Paul Spector. It was originally published in Medium in a version very close to this one. We found it to be an excellent review of the vaccine hesitancy problem, both historically and in its present COVID-19 iteration.
Vaccination and opposition to it is nothing new.
Variolation, infecting someone with material from smallpox pustules to create natural immunity, was practiced in Asia and Africa in the 16th century. Cotton Mather, a Christian minister in Boston, promoted the practice in the 1700’s having learnt the technique from his African slave. Despite its effectiveness, Mather was ostracized.
The smallpox vaccination of the late 18th century promoted by Edward Jenner, an English physician, used cowpox. Although successful at preventing smallpox, one of the most feared illnesses with a death rate of 30%, anti-vaxxers of the day called it a foreign assault on traditional order.
In 1910, Sir William Osler, the father of modern medicine, famously expressed his dismay at the irrationality of the anti-vaccinationists by offering to take 10 vaccinated and 10 unvaccinated people into the next smallpox epidemic. The vaccinated group, he said, could care for the unvaccinated when they inevitably succumbed to the disease and arrange for the funerals of those who died.
The death toll for smallpox is estimated at 300 million in the 20th century alone. In 1979, smallpox became the first human infectious disease to be eradicated by vaccination.
Immunization programs have both continued to prove their worth and stir controversy
Tetanus, a bacterial infection without cure, is fatal in 10–20% of cases. About 34,000 newborns died from neonatal tetanus worldwide in 2015, a 96% reduction since 1988, when an estimated 787,000 babies died from the disease.
Polio, a highly infectious disease with a death rate of one in twenty children and one in three adults, often caused epidemics in the first half of the 20th century. In 1952, 3,145 children died in the US. The vaccine, developed in 1953, has nearly eradicated the disease.
Measles, one of the most contagious viral diseases, claimed 2.6 million lives per year globally before 1963 when a vaccine was introduced. Immunization resulted in an 84% decrease in measle deaths between 2000 and 2016 globally, preventing 20.4 million deaths worldwide.
Between the 1940s and the 1970s, antivaccine sentiment in the US receded somewhat due to three trends: huge advances in vaccine science, public awareness of widespread infectious disease outbreaks (measles, mumps, rubella, pertussis, polio) in children, and a baby boom. This golden age of vaccine acceptance resulted in dramatic decreases in outbreaks, illness and deaths.
Ironically, the unrivalled success of vaccination programs contributed to ending its golden age. By eliminating highly visible outbreaks of infectious disease, vaccines diminished public perception of disease risk. Fear of disease was replaced by fear of adverse events purportedly associated with vaccination. In the 1970s, as more vaccines were added to immunization schedules and anecdotal claims of harm were spread by the media, the antivaccination movement was reborn.
No medical intervention has saved more lives or created more conflict than vaccination.
So how are we to understand vaccine hesitancy?
Vaccine hesitancy is defined as the refusal, delay, or acceptance with doubts about vaccine usefulness and safety. It is recognized by the World Health Organization as one of the ten most important health threats in the world today. The determinants of vaccine hesitancy are complex but can be organized around three issues: confidence, complacency (low perceived usefulness), and convenience (perceived constraints to access).
Confidence, the pivotal determinant, derives from trust. To feel confident about the safety and efficacy of a vaccine is to trust science and technology, pharmaceutical manufacturers, the healthcare system, healthcare providers, policy-making government, and the media that informs the public.
A leap of faith, to say the least.
Trust is necessary when a high level of information asymmetry creates an imbalance of power. The vaccine taker does not have the time, expertise or inclination to assess the data. We choose to trust an expert to help make a risk/benefit-based decision about which we have incomplete information. Such a choice assumes that the trusted experts have correctly assessed the situation and have our best interests in mind.
If trust is lost in the vaccine-related players, it will be placed in other influencers, who may be ill-informed, indifferent to vaccination, or against it.
We live in a time when mistrust is the public’s default position. Mistrust of public health initiatives has been fueled by many things including a partisan media, prominent cases where the medical community was wrong, profiteering pharmaceutical companies, failure of regulatory agencies to protect the public, and an erosion of faith in health experts.
A Gallup poll this year examining confidence in institutions found that less than half of Americans (44%) have a great deal or quite a lot of trust in the medical system and 21% have very little. In 1975, 80% of the population had a great deal or quite a lot of confidence in the medical system and only 4% said they had very little. Loss of faith in the medical system over this period outstrips all other institutions studied.
Vaccine hesitancy also reflects a political divide. Although there is nothing inherently pro or anti-vaccination in Democratic or Republican ideology, it quickly became a polarizing issue. Whether you take COVID seriously, wear masks or get vaccinated has become a way of affiliating with one party or the other.
A poll conducted by the Pew Research Center in July 2020 found that 46% of Republicans saw COVID as a threat to US health versus 85% of Democrats. A Gallup survey at that time reported 94% of Democrats always or very often wore a mask outside the home while 46% of Republicans said the same. Recent polling by the nonpartisan Kaiser Family Foundation found that 75% of Democrats have already been vaccinated vs 41% of Republicans.
Community (also known as herd) immunity is attained when a large proportion of a population is immune to a disease. This can be measured on a global, national or community level. Immunity can be obtained either by making antibodies after an infection or from a vaccine. The percent of a population that needs to be immune to reach herd immunity varies by disease and how contagious it is.
Because measles spreads so easily, 95% of a population needs to be vaccinated to achieve herd immunity. In 2019, a measles outbreak in Clark County, Washington occurred when the vaccination rate in public schools dropped to 77%.
Early in the pandemic, community immunity was estimated to require 60–70% immunity in the US. As more infectious variants have taken hold that estimate has increased to 85%. The race between vaccines and variants is ongoing.
The devastating effects of COVID-19 (3.5 million deaths as of June 1, 2021) has sown fear among the public and healthcare workers. This has lent itself to changes in clinical and personal behavior, much of which is not evidence-based and often detrimental.
The Choosing Wisely Initiative for COVID-19 was created to promote a dialogue between patients and doctors about how to avoid unnecessary practices and choose interventions that are evidence based, safe and necessary. Their 18-member task force is drawn from the fields of public health, epidemiology, general practice, primary care, infectious disease, virology, critical care, internal medicine, pulmonology, pediatrics, oncology, health economics, clinical research, implantation science, and health policy. Patient and civil-society representatives contributed.
It has drawn up a list of things clinicians and patients should question as well as 10 recommendations, 5 for the general public and 5 for physicians. Here are the recommendations for the public.
1. Do use well-fitting masks appropriately, whenever in public.
2. Do avoid crowded places, especially while indoors.
3. Do get tested if you have symptoms of COVID-19, and isolate yourself at home if symptoms are mild.
4. Do seek medical help if you have difficulty breathing, or your oxygen saturation drops to less than 92%.
5. Do get vaccinated as soon as you are eligible, and even if you have had COVID-19 in the past (although there could be a change in expert guidelines on vaccinating previously infected people as more data are accumulated).
Vaccines exist in a very different mindset than other medicines. An individual takes a medication when she is sick and wants to get better. A vaccine is taken in health (or without the disease targeted by the vaccine) in order to remain well and, as importantly, to protect others. Prevention of illness by vaccination requires a willingness to consider future risk to yourself and those around you.
Vaccines must work on both the individual and societal level in order to be effective.
In this way, vaccine acceptance reflects a social cohesion based in sufficient trust of public institutions and a willingness to participate in creating a public good. We therefore should not be surprised at the prevalence of vaccine hesitancy. Numerous studies have documented the conditions that foster social cohesion: low levels of conflict based on wealth/income disparity, ethnicity, race or gender, impartial law enforcement, a sense of engagement in a common enterprise, facing shared challenges and a belief that they are members in equal standing of the same community.
We live in a time when these conditions seem like a utopian dream. This virus has highlighted how divided and unequal we are. Attempts at increasing vaccination rates through educational measures based only on a knowledge-deficit model will not suffice.
51% of Americans are fully vaccinated vs 23.6% of the world population and 1.3% of people in low-income countries. We have long way to go.
Perhaps, among the many ways the virus has transformed how we live, it will remind us that we are in this together. COVID is blind to gender, race, ethnicity, wealth and political persuasion. We need to adopt a similar stance.