Many parents at Lagunitas and Bolinas-Stinson Union School Districts appear to be holding firm in their refusal to vaccinate their children against infectious diseases such as chicken pox, Hepatitis B and measles, despite a new California law passed last year that makes it harder to opt out.

Data collected in December by the California Department of Health shows that the number of kindergarteners who are exempt from vaccines due to personal beliefs has decreased drastically since 2012 countywide, but remained roughly the same in West Marin’s elementary schools. San Geronimo Elementary, one of two schools in the Lagunitas School District, remains an outlier—over half of the school’s kindergarteners are exempt—and parents have continued to opt out this year despite the extra hurdle of obtaining a doctor’s consent, as required by the new law.

“It’s the fear of vaccinations,” said Laura Shain, the district principal. “People were willing to go that extra step to have a doctor sign off, so that shows the opt-outs here were not done for convenience’s sake. It speaks to the fact that our community feels things strongly and is a passionate community.”

San Geronimo suffered through chicken pox outbreaks in 2007 and 2011. Although many non-vaccinated students were excluded from school participation during the outbreak of 2007, none were asked to stay home in 2011.

The new personal belief exemption law forces opt-out students to abstain from school in the event of a reported infectious disease case, and Ms. Shain has assured that exempt students will have to stay home in the event of another outbreak. Despite new regulations, however, the school’s hands are tied when it comes to encouraging parents to vaccinate their children.

“It is a concern,” Ms. Shain said. “But we have to be careful and make sure we don’t cross the line and tell people our opinions on their own health decisions.”

While not as high as the San Geronimo rate, Bolinas-Stinson School also has an eyebrow-raising rate, with over a third of students exempt from vaccines. (The other district in West Marin, Shoreline Unified, has only one opt-out student between Tomales Elementary and West Marin and Inverness Schools.) John Carroll, the superintendent of both the Lagunitas and Bolinas-Stinson districts, said it is a challenge to walk the line between parents’ personal beliefs and student-body health. 

“These are communities with people who are very committed to opting out,” he said. “They see it as a very serious issue.”

At Lagunitas, 92 out of 289 students from all grades have opted out of vaccinations; at Bolinas-Stinson, that number is 30 out of 115. These are troubling numbers for the county’s public health officer, Matthew Willis, who cautioned that school settings can serve as pressure cookers for infectious disease.

“You’re talking about kids being confined in a space for eight hours,” Mr. Willis said. “That’s where I worry most about the spread of an outbreak.”

In a press release issued last week, Marin County Health and Human Services lauded the state’s recent data as indicative of a positive trend that could help keep diseases out of the county. In all, the percentage of kindergarteners with personal belief exemptions in Marin dropped from 7.8 percent in 2012 to 6.5 percent in 2014, after a steady climb from 3.8 percent in 2004.

Private schools in East Marin boasted the biggest changes in their opt-out numbers, Mr. Willis said. Health officials have attributed the opt-out decline to the 2014 law that requires parents to consult a doctor before receiving opt-out consent.

“There was a modest improvement last year, and a more drastic improvement this year,” Mr. Willis said. “That’s a good sign. We tend to see much more rapid spread of a disease in the event of an outbreak for communities with lower vaccination rates.”

He noted that the county’s immunization program surveyed kindergarten parents across the county and determined that many are not receiving information from health care providers about the risks of not vaccinating their children.

“It was clear [from the survey] that parents are looking to make the best decision possible for their families,” he said. “They may not have had access to information, or may have had the understanding that these diseases are a remote possibility. And that’s changed.”

The recent opt-out figures have been brought into focus for public health officials by the measles outbreak that started last month at Disneyland, which has spread as far north as San Mateo and Alameda Counties and into other states across the country. So far, no cases have been reported in Marin.

Mr. Willis has sent letters to all schools in the county that instructed nurses to exclude from attendance any students not vaccinated for measles for 21 days if a measles case appears at their schools. (Mr. Carroll affirmed that he plans to send the same letter to parents in his
districts.)

“We’re fortunate,” Mr. Willis said. “But it may just be a matter of luck. We’ve got our fingers crossed that as this outbreak unfolds, there won’t be measles in Marin County. I’d feel a lot better about that if we knew our communities were being protected.”