A few weeks ago a reader took issue with The PediaBlog’s strong stance for immunizing children completely, and on time. Specifically regarding the post reporting a case of measles in Pittsburgh, and why immunization for one means (according to the concept of “herd immunity”) protection for others, the reader suggests a different approach of advocacy is in order:

If your goal is to convince people to immunize, this lame approach isn’t gonna cut it. I’m assuming you are intelligent – consult a psychologist or behavior specialist to learn another method for changing behavior.


According to a recent study published in Pediatrics and widely reported in the media, the reader may have a point:

Current public health communications about vaccines may not be effective. For some parents, they may actually increase misperceptions or reduce vaccination intention. Attempts to increase concerns about communicable diseases or correct false claims about vaccines may be especially likely to be counterproductive. More study of pro-vaccine messaging is needed.


The researchers looked at previous studies exploring cultural, societal, and political biases and how they affect people’s views of reality, and then predicted (correctly) that fighting preconceived negative notions about the importance and safety of vaccines with factual information would actually backfire:

In particular, some pro-vaccine messages may do more harm than good, especially those targeting misinformation, which is often difficult to correct. The problem is that people often interpret evidence in a biased fashion. As a result, corrective information about controversial issues may fail to change factual beliefs or opinions among respondents who are most likely to be misinformed. In some cases, corrections can even make misperceptions worse. Resistance to scientific evidence about health risks is also a serious concern. It is therefore important to determine whether corrective information about MMR and other vaccines provokes a similar response. We hypothesize that respondents with the least favorable vaccine attitudes will increase their belief in false claims and decrease their intent to vaccinate in response to corrective information.


The researchers used readily available resources and materials produced by the Centers for Disease Control and Prevention (CDC):

We specifically tested 4 strategies commonly used by public health agencies to promote vaccination: (1) correcting misinformation, (2) presenting information on disease risks, (3) using dramatic narratives, or (4) displaying visuals to make those risks more salient or accessible.


In fact, telling study participants frightening narratives or showing pictures of children suffering from vaccine-preventable diseases (in the study’s case, measles) increased fear of vaccines in those with the least favorable attitudes about vaccines and decreased their intent to vaccinate.  Jeffrey Kluger is exasperated:

 As Brendan Nyhan, author of the new vaccine study, told TIME, the harder doctors or public health officials fight to persuade parents to vaccinate their children, the more stubbornly unconvinced some of them remain, asking, “Why are they trying so hard to reassure me that everything is safe?” The fact that it is safe never enters into the equation.

This says much less about vaccines or even parents than it does about the human tendency to cling to—and even fight for—ideas and beliefs that just ain’t so.


Indeed, the researchers found none of the interventions helpful in people who were least likely to vaccinate.  Pediatrician Russell Saunders didn’t need this study to tell him what he’s already learned from years of clinical experience:

Declining vaccines is, at best, misguided. But of course those inclined to refuse them don’t agree with me, and I’m not going to try to change their minds. I’ve had too many of that kind of conversation over the years to hold out hope that anything I can say will sway them.

Which is precisely the problem.

There are few questions I can think of that have been asked and answered more thoroughly than the one about the safety and effectiveness of vaccines.

The measles-mumps-rubella vaccine does not cause autism.

The HPV vaccine is safe.

There is no threat to public health from thimerosal.

I can say all of this without hesitation because these concerns have been investigated and found to be groundless. But no amount of data seems sufficient to convince people who hold contrary beliefs.

So then, if the entire apparatus of medical science has bent itself to the task of reassuring the public about the safety of vaccines and still comes up short in vaccine refusers’ estimation, how can I possibly rely on that apparatus to undergird conversations about other potentially fraught topics? If a conclusion as sound as the importance of immunizing your kids is suspect to them, what other conclusions may I rely upon?


The take-home message is, I think, pretty simple.  We all know you’ll never convince another of what you believe is true if they have already made up their mind.  It’s just not vaccines: there are countless other examples where people won’t have any of what’s being said to them.

The push-back I have received from those very few parents who refuse to vaccinate their children — in the office over nearly 24 years and from several readers on The PediaBlog — is more understandable to me after reviewing this study.  Not acceptable to me as a pediatrician morally tasked to protect individual and public health; nor as a father morally responsible for protecting his own children’s health and safety; nor as a spiritual man who tries to see the good in everyone, but understandable.

Is it time for pediatricians to chill?  If they are not making things better, are our messages making things worse?  Do we, as our reader at the top of this post suggests, “consult a psychologist or behavior specialist to learn another method for changing behavior?”  Or do we accept that nothing we do or say will change minds-made-up and just move along,  hoping that those who refuse vaccines for their children remain where they are — not in the mainstream of ideas, but at the extreme fringe — below the threshold where the threat to herd immunity puts us all in grave danger?

More PediaBlog on vaccines here.