Jake Reagan never thought his Facebook post would blow up the way it did.

Sure, the onetime executive chef at Seattle’s Ponti Seafood Grill, now residing on a farm and event venue on Vashon Island, was characteristically blunt. “I know there are parents here against immunization,” he wrote late last month on a community-wide page called VashonALL. “Tell me why and who you are so we can stay away from you. Not something to risk now that measles is back.”

An avid watcher of the news, he had been alarmed by the nationwide measles outbreak that began in Disneyland in December and has now spread to more than 100 people in 15 states, including Washington, where four residents have come down with measles. He also knew that Vashon has one of the highest vaccine refusal rates in the state—indeed in the country.

This year, 27 percent of students in the island’s school district are not fully vaccinated, according to district nurse Sarah Day. Among kindergarteners, 43 percent are not. That’s more than three times last year’s rate for Seattle (although nearly two dozen individual Seattle schools have a similarly high percentage of unvaccinated kids, according to a map released last week by Public Health-Seattle and King County.)

Both Reagan and his wife Megan worried that Vashon’s low immunization rate could endanger their 15-month-old. They had particular insight into what the world was like before the development of vaccines: Megan’s grandmother contracted polio in her late 20s and has spent the past 50 years in a wheelchair.

Yet Reagan was taken aback by the response to his post—so much so that he didn’t want to talk about it on the record, although his wife would. Within a week, 267 responses rolled in. Many were not only blunt. They were angry. “What word would you use to call someone intentionally risking the lives and health of others?” one islander posted in reference to non-vaccinating parents.

“I think ‘murderer’ is the word you might be looking for,” replied another. Other words that popped up in comments, referring to vaccine refusers, as the days went on: “stupid,” “irrational,” “self-centered,” “myopic” and “batshit.”

“Oh calm down everyone. I regret starting this,” Reagan interjected. His plea went unheeded.

In a new twist to the vaccination debate, parents who support immunization are becoming militant. On websites around the country, some have even called for non-vaccinating parents to be reported to child protective services or excluded from pediatricians’ offices.

Jeffrey Duchin, immunization section head for King County’s health department, says he isn’t in favor of outright hostility. On the whole, though, he sees the new tenor of conversation as positive. After all, he points out, anti-vaccine activists have long and stridently expressed their views—centered on a belief, contrary to scientific evidence, that vaccines can harm kids rather than protect them. One such activist on Bainbridge Island named Michael Belkin is part of an anti-immunization band whose repertoire includes the song “Vaccine Gestapo.”

Says Duchin: “I think it is important to understand that people who support vaccines have equally strong views.”

You might think Celina Yarkin would agree. She’s a Vashon parent and farmer who has worked for the past five or six years to increase the island’s vaccination rate, in large part through educational posters put up in the schools.

Yet she worries: “People feel alienated if they’re pushed too hard.” Rather than change their minds, she says, they’re likely to “shut down.”

Day, the district nurse, who has been coordinating with Yarkin on educational materials, agrees: “I think people stop listening when they get mad.” As a result, she says, “I’ve tried to do as much research as I can about positive messaging.”

Still, illustrating just how hard it is to get a pro-vaccine message across, Yarkin and Day, along with public-health officials they’ve been working with, stirred resentment even before the latest measles outbreak turned up the heat.

Last June, two women wrote an article for an island publication called The Loop that portrayed pro-vaccine advocates as “bullies.”

“There is a growing culture of shaming and judgment with regard to vaccine choices,” read the June piece by March Twisdale and Karen Crisalli Winter. So nervous has it made people about discussing the subject, the piece continued, that “a secret, invitation-only Facebook group has been formed for parents who are seeking support and information in a safe environment.” Twisdale and Winter had recently held a Vashon screening of the documentary The Greater Good, which features three families who believe their children were harmed by vaccines. In conversation before and after the screening, according to the Loop article, several parents “experienced significant fear during casual conversation, stopping mid-sentence and visibly shaking.”

Reached last week by phone, Twisdale, who for years has raised questions about the safety and effectiveness of immunizations, and has given her children some vaccines but not others, says the parents were scared that their reputations around the island would be compromised if they were identified as holding anti-vaccine views.

If so, it’s far from clear that “bullying” is the reason why. One example cited by Twisdale and Winter is a school poster noting that breast milk has as much aluminum as vaccines. The poster, according to Day, was meant to allay fears of dangerous “toxins” in vaccines and show that the body produces some of these same chemicals. A student, however, interpreted that to mean that breast milk was actually dangerous and conveyed that information to his mother, who complained to Twisdale.

Day expresses dismay that even factual information like that was misconstrued and seen as inflammatory. As a result, she says, “we’re flummoxed about what we can do in terms of education.” Meeting one day last week, she and Yarkin planned to plod on with their materials—one of which will be a projection showing the impact of a hypothetical measles outbreak on the Vashon student body. (Unvaccinated students would be excluded from school for what could turn into months, given the 21-day incubation period of measles, which would be multiplied many times over if a number of kids came down with the disease.)

Yet, Day says. “We need to be really careful. We’re kind of walking on eggshells here.”

Researchers and public-health officials have long been perplexed about how to overcome resistance to vaccines. One particularly depressing study last year, by Dartmouth political scientist Prof. Brendan Nyhan, showed that pro-vaccine messages—even those based on a wealth of scientific data—can backfire and make parents less likely to vaccinate. Nyhan has said he isn’t exactly sure why, although others have speculated that a conspiracy mindset among some vaccine skeptics may have something to do with it.

So where do vaccine advocates go from here? One tactic is to stop relying on persuasion and lean more forcefully on parents. An Everett state representative named June Robinson, who works as a manager for the county health department, last week introduced a bill that would no longer allow parents to opt out of vaccination for reasons of “personal belief.”

The state has already had some success with curtailing the opt-out option. In 2011, the legislature passed a law requiring parents who wish to bypass vaccination requirements to turn in a form signed by a physician. That was a couple of years after a national ranking showed Washington had the highest vaccine-exemption rate in the country for kindergarteners—7.6 percent. The rate now stands at 4.6 percent, putting us “in the middle of the pack” among states, according to Washington Department of Health spokesperson Paul Throne.

A Seattle-based nonprofit called Within Reach is trying another approach. Working for the past few years on pilot programs in north King County and Bellingham, it has recruited parents to talk to other parents about the importance of vaccines. The nonprofit is targeting people who are “on the fence” rather than diehard vaccine refusers whose minds may never change, according to Mackenzie Melton, a coordinator of the program.

“We’re really focusing on the positive,” she stresses. “We don’t want to pit parents against each other.” To that end, the nonprofit tells its volunteers to “work on empathy and trust-building,” to perhaps share their own “journey” with vaccine decision-making and to avoid “bludgeoning” other parents with science.

It’s too early to judge whether this approach is proving persuasive, according to Group Health Research Institute’s Clarissa Hsu, who has been evaluating the data. Yet Melton feels that the program is making headway.

Bellingham’s Kathy Hennessy had been working on vaccine education for some time on her own before joining Within Reach. A stay-at-home mom married to a scientist, she set up a Facebook page called Informed Parents of Vaccinated Children because she believed that “there weren’t a lot of places people could ask questions and get a respectful answer.”

She doesn’t get upset when parents don’t follow the exact vaccine schedule recommended by the Centers for Disease Control and Prevention—a schedule that includes many more shots than when most of today’s parents were kids. If parents are worried about getting a bunch of them at one time, she says she’ll encourage them to talk to their doctor about spacing them out.

And she’s willing to engage parents at length. She remembers one mom she went back and forth with over the meaning of a federal database of suspected adverse reactions to vaccines. The mom was worried about the alarming cases reported. Hennessy explained that they were reports only; no link to vaccines had been confirmed.

A little while later, she says the mom posted to her Facebook wall that she had just gotten back from getting her child vaccinated for the first time.

nshapiro@seattleweekly.com