Many people search for health information online, (paging Dr. Google), including the visual, social media platform Pinterest. And a recent study published in Vaccine found 75 percent of select related pins do not favor vaccination.

The study authors said that few studies of vaccination representation on social media have been done to date. But based on what’s out there, data show negative HPV-vaccine videos are liked more on YouTube than positive or neutral ones, and general vaccine-themed videos are rated and liked more despite there being a greater amount of positive and ambiguous videos. The sole Twitter study conducted on representation found the majority of tweets about vaccination promoted "substantiated medical information."

Given Pinterest is pretty much uncharted territory, plus the fact that it now boasts more than 100 million active "pinners," the authors were curious to see how vaccinations were portrayed on Pinterest and how some of the platform’s users engage with this content. They manually searched the social platform for topics related to vaccines and depression, collecting 800 pins in total. After these pins were analyzed to determine if users were pro- or anti-vaccine, they found 75 percent of the results were negative.

Some of the sample pins authors included in their study included ads about the HPV-vaccine Gardasil, claiming it’s "helping destroy the lives of little girls (and now boys too) one injection at a time," as well as a photo of a small child on a ventilator allegedly due to "vaccine injury." When Medical Daily conducted their own search for vaccine-related pins, the first result is a story titled, "200 Evidence-Based Reasons NOT to Vaccinate" and "The Shocking Truth about aborted human fetal cells in vaccines." There’s also one story claiming "gentle vaccine detox" to remove heavy metals, and in a separate pin, a recipe for a mercury and heavy metal detox smoothie.

It wasn't all negative, though. There are positive and neutral pins, such as one for the Centers for Disease Control and Prevention’s (CDC) vaccine schedule. There are also pins listing vaccine-friendly doctors by state, reasons to believe the CDC is right about vaccination, and just a general inquiry for more knowledge. Not to mention these 800 pins are out of more than 50 billion overall pins, per Pinterest.

The study's findings are a shift from the studies done in the past; in the mid-2000s, vaccine-related posts on YouTube and MySpace were negative just 25 percent of the time. It's a concerning trend, the study authors wrote, that "public sentiment may be impacting the level of uptake of vaccines crucial to the continued prevention of morbidity and mortality due to infectious, vaccine preventable diseases."

They continued: "While most pins in this study did not use narrative or statistical information, for the ones that did, pro-vaccine pins still featured more statistical information while anti-vaccine messages featured more narrative information. Several studies have noted that narrative information referring to adverse vaccination events will decrease vaccination intentions, as well as narratives having an overall stronger influence than statistical information."

Outside of social media platforms, studies have shown visiting anti-vaccination websites for 5 to 10 minutes can increase perceptions of vaccination risks and decrease intentions to vaccinate. And yet, much of the anti-vaccine rhetoric — it's ineffective; it infringes on civil liberties; and it causes autism — have not been upheld by science. In fact, it seemed the anti-vaccine rhetoric might be squashed after California's measles outbreak.

Dr. Neal Goldstein and his colleagues at Drexel University responded to the study, also published in Vaccine, suggesting these findings aren’t new and "it’s been going on for some time now."

"It's worthwhile to make the statement we need to do more, but we're doing quite a bit; maybe people can't hear the message because they're being bombarded with scientific data, Goldstein, of Drexel University Dornsife School of Public Health, said in a press release. "The question is how do we do better? How do we become better advocates for science in the public?"

Goldstein believes perpetuating anti-vaccine rhetoric is "a systemic issue in which institutes play a vital role." Some of Pinterest's users are speaking out, but this courage of conviction should exist in the "pure research community," Goldstein said.

As for the study itself, the authors concluded future research on the topic should consider social media platforms, like Facebook and Instagram, and "build a more robust field of literature regarding the portrayal of vaccines and vaccinations on social media platforms."

Source: Guidry JPD, Carlyle K, Messner M, Jin Y. On pins and needles: How vaccines are portrayed on Pinterest. Vaccine. 2015.

Goldstein ND, LeVasseur MT, Purtle J. Is this thing on? Getting the public to listen to the pro-vaccine message. Vaccine. 2016.

Updated | Pinterest provided data for the site's total number of pins.

Correction: This article originally incorrectly stated that Pinterest boasts 74 million users. Pinterest boats more than 100 million active users.