Dangerously high numbers of unvaccinated children attend classes at dozens of elementary schools across Maine, with immunization opt-out rates reaching levels where an outbreak of infectious diseases could sicken many children, according to public health experts who reviewed statewide data obtained by the Maine Sunday Telegram.

In the schools most at risk, children who haven’t been immunized account for more than 10 percent of the kindergarten or first-grade students, threatening the “herd immunity” that prevents diseases like measles, mumps, polio and pertussis from spreading. In some schools, more than 20 percent are unvaccinated, according to data compiled for the Telegram by the Maine Center for Disease Control and Prevention.

The reason: Parents refusing vaccines for their children, mostly opting out of required immunizations on philosophical grounds.

State lawmakers are considering bills that would make it more difficult for parents to forgo vaccines for schoolchildren. The bills – including one that would require a consultation and signature by a medical professional before being permitted to opt out on philosophical grounds – are being hotly contested by pro- and anti-vaccination advocates.

The opt-out rates have been publicly released on a school-by-school basis for the first time, in response to a public records request by the Maine Sunday Telegram. Parents can look up their school in a searchable database at www.pressherald.com/vaxmap2015.

The decision to skip vaccines is putting students at greater risk of contracting infectious diseases, public health officials say, especially when populations of unvaccinated children reach thresholds that endanger herd immunity.

Herd immunity can start waning for some diseases when less than 95 percent of the population is vaccinated, according to the U.S. Centers for Disease Control and Prevention.

Most vulnerable are immune-compromised children, perhaps those with leukemia or cystic fibrosis – diseases that suppress the immune system – sitting in the same classroom as an unvaccinated student.

“Measles can be a death sentence for any child,” said Dr. Laura Blaisdell, a Yarmouth pediatrician. “For an immune-compromised child, the risks from measles are vastly higher.”

DATA MORE MEANINGFUL TO PARENTS

In at least 39 primary schools, 80 percent or fewer students are getting the measles shot, including only 37.5 percent of kindergartners at Fiddlehead School of Arts and Sciences in Gray, a public charter school, and 55 percent of first-graders at Bay Ridge Elementary School in the Washington County town of Cutler.

The state keeps track of each school’s vaccine coverage for individual vaccines, in addition to overall opt-out rates. The measles vaccine was linked to autism in a 1998 British medical journal study that has since been debunked and retracted.

Measles is one of the most contagious diseases, and an outbreak this past winter at Disneyland in California sickened hundreds.

The Maine CDC released the data to the Maine Sunday Telegram after a Freedom of Access Act request for the 2014-15 school year. The data show that the bottom-line voluntary opt-out rate for children entering kindergarten has declined from 5.2 percent last year to 3.9 percent this school year – which is still above the national average.

However, there are wide variations among schools, as the opt-outs are not evenly distributed.

Many schools have no students opting out.

But some, like Pond Cove Elementary in Cape Elizabeth, Small Elementary in South Portland, and Union, Camden-Rockport and Hope elementary schools in Knox County, have kindergarten or first-grade opt-outs at rates at least triple the state average.

Those schools are far from alone.

At least 60 elementary schools across Maine have vaccination opt-out rates of 10 percent or higher, according to the database, putting them at greater risk for infectious disease outbreaks.

Blaisdell said being able to access school-level information is more meaningful to parents than a statewide number.

“Having a statewide percentage doesn’t mean much to a father taking his child to a school,” Blaisdell said. “We will now have a greater understanding of how these numbers affect local communities in ways that we haven’t had before.”

Tonya Philbrick, director of the Maine Immunization Program for the Maine CDC, said publicly releasing the data is “an opportunity for public education, and to partner with schools to work on vaccine coverage.”

STILL GAPS IN THE DATABASE

The problem is likely more acute than what the data are currently showing. About 85 elementary schools are not in the Maine CDC database, either because they didn’t report or because the state has yet to record the information. The Maine CDC says it is working to add more schools to the database as the information comes in.

Philbrick said schools were required to submit the data by Dec. 15, and she’s looking into why there are about 85 missing schools in the public database.

The Telegram has put the information into an online searchable database and an interactive map on its website, at www.pressherald.com/vaxmap2015.

The data show that low-income communities tend to have much less philosophical resistance to vaccines, as many schools in Aroostook County or in lower-income areas of Portland have no parents opting out on those grounds.

A study by Texas State University says there’s a sociological component to reasons why parents opt out, as parents who choose to delay or forgo vaccines are more likely to rely on social networks to make decisions on vaccines, whereas parents who fully vaccinate rely more on medical authorities.

Emily Brunson, an anthropology professor at Texas State who has researched the phenomenon, said for some parents, what friends and family believe is much more important than messages received through the media or at the doctor’s office.

“The social networks are what’s driving this, among a subset of the population,” Brunson said, adding that it’s online social networks such as Facebook and in-person interactions that are molding opinions. The mainstream media are secondary for this group, she said.

The result is a clustering effect, where vaccine refusal takes hold in certain communities, often more affluent, liberal-minded or libertarian areas. In Maine, areas with more liberal or libertarian beliefs, and the “back to the earth” organic movement have led some to distrust traditional medicine like vaccines, experts say.

The lack of trust was on full display at a legislative public hearing last week on the vaccine bills, where some who testified spoke of high risks from vaccines – such as autism – that are not supported by any scientific research. Vaccines are overwhelmingly safe and side effects that result in significant harm are extremely rare – one in 500,000 or less, according to the U.S. CDC.

“We live in the age of information, and the age of misinformation,” said Dr. Dora Anne Mills, a former Maine CDC director who is now vice president for clinical affairs at the University of New England.

Nevertheless, it’s not surprising to see vaccine skepticism coalesce in some areas of the midcoast, Mills said.

“There’s a strong libertarian viewpoint as well as living a natural and organic lifestyle. You are seeing a combination of those two lifestyles on the midcoast,” she said.

PARENTS TALK ABOUT THEIR DECISIONS

Chelsea Kidd of Rockland, the parent of a 5-year-old, said she has seen the anti-vaccine sentiment firsthand, and it has made her careful about making friends, and who her child becomes friends with, especially as he starts to get older.

“I want my child to be scientifically literate,” Kidd said. “I don’t want anyone spreading weird ideas to my kid.” She said she also has a moral problem with people who choose not to vaccinate their children, because it’s endangering others.

Kidd said, though, that’s it’s socially awkward to ask people’s views on vaccinations.

“I always want to ask about it, but I don’t know how to,” Kidd said.

In southern Maine, elementary schools in two bordering communities – Pond Cove in Cape Elizabeth and Dora L. Small in South Portland – have high opt-out rates. At Small, in a trendy area of South Portland near Willard Beach where students walk to school, parents of 20 percent of first-graders have opted out of giving vaccines to the children, the second-highest opt-out rate in the state for schools with at least 15 first-graders.

Kate Sibole, 42, of South Portland, whose children attend Small school, said she finds herself in the middle of the vaccine debate. She gives her children vaccines, but on a delayed schedule.

“I’m not anti-vaccine. I’m anti the vaccine schedule,” Sibole said.

There’s no danger to giving children vaccines according to the schedule recommended by pediatricians, according to the U.S. CDC. But many pediatricians agree to the alternative schedules at the urging of parents wary of vaccines, because it’s better than not vaccinating.

Sibole said she’s influenced by friends and family’s views of vaccines – and many are skeptical of the vaccines – as well as her personal experiences.

She said she was affected by this year’s measles outbreak in Disneyland, and she moved up some measles shots for her children as a result, delaying other vaccines instead.

But Sibole said she trusts the sharing of information about vaccines from her friends and family, and she has never felt ostracized for her views.

“I feel it’s about fact-finding. It’s never arguing or debating. People share and say, ‘Oh, have you heard about this?'” Sibole said.

Erin O’Connor-Jones, a Small school parent, said the Small school community is extremely diverse – economically, socially and by lifestyle choices – with parents having many different viewpoints and parenting styles.

But she said she wishes parents would consider other children – especially immune-compromised students – when deciding whether to vaccinate.

“What people may not realize is a decision to immunize or not immunize your child can have an impact on the local community,” O’Connor-Jones said.

‘PARENTS SHOULD BE VERY CONCERNED’

Dora L. Small School principal Diane Lang said she just got the state report this past week on the school’s opt-out rates, and she plans to discuss it with the school’s staff. She said she believes the 20 percent opt-out rate for first-graders is an anomaly and not reflective of long-term trends at the school.

Shannon Gervais of Buxton has a son in fifth grade who is immune-compromised from respiratory ailments. She said he is much stronger than a few years ago, so she’s less worried about exposure. But Gervais said she’s pleased to see the vaccine opt-out information is now available by school.

“I think parents should be very concerned,” said Gervais, who keeps close tabs on her son’s health. “I would have been much more interested in the numbers of unvaccinated by grade three or four years ago. My son missed three months of kindergarten.”

Blaisdell, the Yarmouth pediatrician and a statewide advocate for improved vaccine coverage, said she has researched vaccine refusal and believes momentum is building in favor of vaccines.

Vermont and California appear to be on the verge of approving greater restrictions for opting out of vaccines, following Oregon and Washington state, where opt-out rates have also been high. The California measles outbreak may be helping to shape opinions that these are diseases with real consequences, Blaisdell said.

People forget that measles, polio, rubella and other diseases that used to be commonplace in the 1950s and 1960s – sickening, killing and maiming thousands – are now mostly eradicated, thanks to vaccines.

“Anyone who says these are not serious illnesses has not seen enough of them,” Blaisdell said. “We are at a crossroads. We have to weigh personal choice versus community responsibility, which is what vaccines are all about.”