As we report on measles outbreaks and outbreaks related to other vaccine-preventable diseases, it's important to stick to the science — and to use neutral language in describing peoples' positions.
In particular, avoid the use of the terms "anti-vax" and "anti-vaxxer." These labels are often inaccurate and too inclusive because many people who decline to vaccinate their children may only decline a particular vaccine and not all vaccines. And some people opposed to vaccines are opposed only to the mandatory aspect and do not necessarily object to voluntary vaccination. There is a spectrum of views here that we need to represent fairly.
Action words and details about a person's or group's views are almost always more effective than labels. We might say, for example that they "oppose mandatory vaccination programs." Or that they, "don't trust the overwhelming scientific evidence supporting the safety and benefits of vaccines."
When terms are needed, "vaccine hesitant" or "vaccine resistant" can accurately describe an individual's position without carrying the pejorative weight of "anti-vaxxer." It also acknowledges that some parents are of mixed minds on vaccines, and not necessarily completely opposed. These in-between people have told us they view "anti-vaxxer" as disrespectful – which can have the effect of shifting their opinions away from our scientific-based coverage to the unscientific misinformation that is out there.
Still, some of the most widely seen websites devoted to vaccine opposition are filled with misinformation about safety. We need to label that clearly. We should strive to describe misinformation, whether deliberate or not, as just that – without weighted language.