More recently, social media and vocal anti-vax celebrities have fueled the spread of the misinformation that prompts parents to make this dangerous choice for children too young to have a say. As the anti-vax movement grows (and their seemingly insane memes and rants go viral), it’s easy for the average bear to blame disgraced doctor Andrew Wakefield’s study or oh-so-vocal anti-vaxxer Jenny McCarthy for the increased acceptance of this dangerous practice.

They may get most of the limelight and fuel most of the stereotypes, but Wakefield, the celebs who embrace his fake research, and the folks raging about thimerosal and mercury on social media comprise just one segment of the ever-growing population who refuses to get vaccinated these days, all contributing to this global health crisis.

The so-called “3 Cs” of vaccine hesitancy—confidence, complacency, and convenience—paint a better picture of the various motivators behind unvaccinated folks today. Let’s dig a little deeper into those three categories, courtesy of this 2014 WHO report.

In the “3Cs” model, confidence is defined as trust in 1) the effectiveness and safety of vaccines; 2) the system that delivers them, including the reliability and competence of the health services and health professionals and 3) the motivations of the policy-makers who decide on the needed vaccines. Vaccine complacency exists where perceived risks of vaccine-preventable diseases are low and vaccination is not deemed a necessary preventive action. Complacency about a particular vaccine or about vaccination in general is influenced by many factors, including other life/health responsibilities that may be seen to be more important at that point in time. Immunization program success may, paradoxically, result in complacency and ultimately, hesitancy, as individuals weigh risks of vaccines against risks of diseases that are no longer common. Self-efficacy (the self-perceived or real ability of an individual to take action to vaccinate) also influences the degree to which complacency determines hesitancy. Vaccine convenience is measured by the extent to which physical availability, affordability and willingness-to-pay, geographical accessibility, ability to understand (language and health literacy) and appeal of immunization services affect uptake. The quality of the service (real and/or perceived) and the degree to which vaccination services are delivered at a time and place and in a cultural context that is convenient and comfortable also affects the decision to be vaccinated and could lead to vaccine hesitancy.

Confidence, of course, is most-easily represented by the anti-vax movement that makes so many roll their eyes at the ridiculousness of it all. But the other two Cs are important as well. If confidence can be oversimplified to “I don’t trust it,” complacency can be boiled down to “I don’t need it,” and convenience comes down to “I can’t get it.” Thus, we’re dealing with not just issues fueled by weird conspiracy theories, but also issues of arrogance and accessibility.

It’s crucial to remember that vaccine hesitancy is a complex, multi-tiered issue affecting the entire planet, and it shouldn’t be defined solely by the well-known maniacs of the anti-vax movement that provide so much fodder for disdain and dismissal. Only then can we push through and conquer the other two Cs and get our society back to the herd immunity we all need and deserve—and that medical professionals worldwide worked so hard to secure.