Can we ever convince 100% of the population that it’s safe to vaccinate?


Measles is a highly-infectious disease that has all but been eradicated by vaccines.

Yet, more children are remaining unvaccinated against measles, which may be resulting in some of the highest numbers of measles cases reported in the US in decades.

Maybe we simply need to get better at distinguishing between science publications and opinion articles. Or maybe we need to study the data on autism and learn how vaccines work.

Or maybe 100% of the population will never believe that it’s safe to vaccinate.

After all, in 2014, Trump tweeted:

“Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn’t feel good and changes – AUTISM. Many such cases!”

Let’s take a look.

It’s impossible to convince 100% of the population that science-based decisions, like vaccinating (most) children, is safe.

it’s easy to criticize vaccines when they’re not affordable

Vaccination rates are lower for children in poverty; some parents forgo vaccines because they can’t afford to make the trip to the doctor or they don’t have insurance to pay for vaccines.

some anti-vaxxers have legitimate medical reasons

A really small population must skip vaccines for medical reasons, like if a child has a compromised immune system he or she might need to forego them. This works when most of the people in a population are vaccinated because these unprotected individuals probably won’t encounter the disease.

This is referred to as the herd immunity, when enough people are vaccinated that a pathogen can’t find new human hosts to which to spread.

when religious reasons are cited

Many states allow non-medical exemptions to vaccination based on “philosophical” grounds. With this, a large outbreak of measles in 2014 was mostly within an unvaccinated community of Amish in Ohio. This year’s outbreak in New York and New Jersey is mostly within the Orthodox Jewish community.

conspiracy theorists aren’t going away

Conspiracy theories are not evidence-based; they exist despite evidence to the contrary. The methods used to develop conspiracy theories are opposite of that which science uses: A conspiracy theory begins with an idea, and then evidence is found to support it.

Conspiracy theories may be popular because they help people to feel more control over the events of their lives.


Alex Jones pushed a conspiracy theory on his website Infowars that the Sandy Hook elementary school massacre was staged by the government in order to push an anti-gun agenda.

In Newtown, Connecticut, in December 2012, a gunman killed 20 young children and 6 adults at the Sandy Hook Elementary School, in an attack that is among the five deadliest mass shootings by a single gunman in US history.

The people who believe Jones’ conspiracy theory harass and taunt the families of the victims. And, at the end of each Infowars program, a list of Infowars-branded dietary supplements is made available for purchase.

Incidentally, President Trump called in to Alex Jones during his on-air program. “You have an amazing reputation,” Trump said in 2015. “I will not let you down.”

Psychologists believe that theories like this help people to feel more control over the terror of random school shootings.

respect for scientists

We don’t have the time or ability to learn about everything, and so we often look to experts for their conclusions. It’s why we visit doctors when we’re sick or hurt, or why we defer to climate scientists that have spent their lives studying climate models.

A 2015 Pew Research study shows:

When participants were asked if childhood vaccines should be mandatory…

68% of non-scientists agreed
and, 86% of scientists agreed

There is a gap between what non-scientists believe and what scientists believe. Does this mean we don’t value science or are we simply ignorant?

The same 2015 Pew Research study shows:

When participants were asked if climate change is caused by human activity…

50% of non-scientists agreed
and, 87% of scientists agreed

Again, there is a gap between what the data shows and what people believe.

Interestingly, in 2015, slightly more scientists agreed that human-activity controlled climate change is true versus the percentage of scientists that agreed that vaccines should be mandatory.

why we don’t believe science

Some people give more weight to personal stories or testimony than to scientific research maybe because, for some, data is too impersonal and difficult to understand.

A story about the danger of vaccines may be more relatable, for example.

cognitive bias

We may bring our bias to the way in which we perceive information.

the Dunning-Kruger Effect

This effect states that people with the lowest levels of actual knowledge tend to have the greatest degree of overconfidence in their own expertise.

In a survey to 1310 US adults, over a third of respondents believed they knew as much or more about the causes of autism than doctors and scientists and that this overconfidence was highest when respondents had the lowest levels of actual knowledge.

confirmation bias

People tend to seek out information that confirms (or doesn’t challenge) the conclusions they already have. In other words, we will work to discredit or avoid information that might require us to reconsider our pre-existing beliefs.

This is especially true when taking the other side could create conflict within our social circle (like a political party, for example).

anxiety over vaccines

Studies have shown that 40% of parents in the United States have “tremendous anxiety” about vaccinating their children, but only about 3% are actually anti-vaccine.

Some states force parents to go through a 30-minute vaccine education program if they want to seek a waiver to a child’s required vaccine. With this program, waiver requests have dropped by nearly half.

fear of unknown

People can be uncomfortable with events that don’t have clear causes, and when we don’t know something, we tend to fill in the information ourselves.

Take autism.

A parent could easily reach for an explanation that makes sense to them. Consider this: the years that a child is typically diagnosed with autism are also the years that he or she is being vaccinated. A connection between the two–even though there is no scientific evidence–is a way to fill in the information.

there’s a lotta bad science out there

People often rely on what they THINK is credible science, when it really isn’t.

Climate change deniers often cite climate skeptics to argue that the science isn’t settled on the issue. Yet, scientific consensus is as overwhelmingly unanimous on human-caused climate change as it is on the safety of vaccinations.

For example, people who oppose vaccinations look to Andrew Wakefield to make their case. Geek out on Andrew Wakefield and where anti-vaxxing started here.

advocacy groups and economic special interests

These groups make it easy for people to cherry-pick data. And, making a set of “alternative” facts available allows people to confirm their biases.

Plus, the amount of misleading information put out by industries that hope to have some sort of edge (by evading climate-related restrictions, for example) can be overwhelming.


Historian Greg Eghigian from Penn State University draws a parallel between the people that believed in UFOs during the Cold War and modern anti-vaxxers and climate change deniers.

“One of the things that marks the long history of this [UFO] movement is the question of mistrust, and I see this as part and parcel of some of the skepticism we see out there today,” said Eghigian. “Although there are some differences, the UFO debate was kind of the granddaddy of them all and could be a model for looking at some of these other controversies.”

The anti-vaccine movement is popular among people who are deeply suspicious of large corporations.

Considering the massive undertaking involved in researching and producing vaccines, they’re mostly done by large pharma companies, and these companies are among those that this population is most suspicious of.

It’s possible to have 100% consensus on science-based policy.

respect for scientists

Expert consensus is a powerful thing. We don’t have the time or capacity to learn about everything, and so we frequently defer to the conclusions of experts. It’s why we visit doctors when we’re sick or hurt. The same is true of climate change: most people defer to the expert consensus of climate scientists so that we can move forward with innovation and policy.

the way science works

Scientific conclusions can be overturned, but not through discussion or debate or wild theories. Science is changed and advanced through evidence that is gathered through well-designed studies that are replicable. The evidence is then published by peer-reviewed journals, opening the discussion to other experts for debate and study. Through this, an understanding of the world continues to move forward.

With this, we’ve developed vaccinations, antibiotics, and endless other scientific “miracles.”

Be the first to comment

Let's Talk