The number of Maine children entering kindergarten without required vaccines increased in 2016-17, alarming public health advocates because it means there’s a higher chance of infectious disease outbreaks, such as measles, pertussis, or chicken pox.

The rate of parents opting their children out of immunizations for non-medical reasons jumped from 4 percent to 4.8 percent, according to new data from the Maine Center for Disease Control and Prevention. Five percent of Maine kindergarten students is about 600 children.

“This is extremely distressing,” said Peter Michaud, associate general counsel of the Maine Medical Association and chair of the Maine Immunization Council. Michaud is also a nurse. “People are not only putting their own children at risk of diseases, but others as well.”

In 2013-14, Maine had a 5.2 percent opt-out rate, which was fifth-highest in the country for that year. The Maine rate declined in the intervening years before climbing in 2016-17. A state-by-state comparison for 2016-17 will be released by the U.S. Centers for Disease Control and Prevention this fall.

In Maine, parents can opt out of vaccines simply by signing a form objecting on philosophic or religious grounds, and Maine has one of the most lenient laws in the country allowing parents to opt out. Attempts to make it more difficult for parents to forgo vaccines failed in 2015 when the Legislature was unable to override a veto by Gov. Paul LePage.

A BREAKDOWN IN HERD IMMUNITY

Some schools have opt-out rates much higher than the state average, including Breakwater School in Portland, with 33 percent of kindergartners and 21 percent of first-graders attending school without having their vaccines. Mount Desert Elementary and Phippsburg Elementary both had 25 percent of kindergartners opting out.

Where there’s a concentration of unvaccinated children, outbreaks are more likely because herd immunity – which protects those who cannot be immunized, such as babies or children with cancer who are unable to receive vaccines – breaks down. Some of the highest rates of unvaccinated children were in small private schools, such as Breakwater and ChildLight Montessori School in York County, where 40 percent of kindergartners were unvaccinated.

While it’s unclear whether school vaccinations are directly related to the surge in pertussis cases in 2017, Maine has had 227 pertussis cases through June of this year, compared to 117 through June, 2016. Sixty-one percent of pertussis cases involved school-aged children, according to the Maine CDC.

Several schools sent notes home to parents this school year warning that children had contracted pertussis, or whooping cough, including Yarmouth, Waynflete, South Portland and SAD 51, which includes Cumberland and North Yarmouth.

Maine had 21.1 cases of pertussis per 100,000 people in 2015, compared with the national average of 10.3, the most recent national comparison available.

STILL A LOT OF FEAR, MISINFORMATION

In 2012, Maine had a spike in pertussis cases to 737, and in 2016 Maine had 256 cases.

Maine will be adding a seventh-grade booster shot for pertussis starting in the 2017-18 school year, which public health advocates say should help reduce pertussis cases in middle and high schools.

The Maine CDC in June reported one case of measles in the Farmington area, the first measles case in the state in 20 years.

Michaud said despite efforts by public health officials to educate the public that vaccines are overwhelmingly safe and effective, there’s still a lot of fear about vaccines. A discredited 1998 study that has since been retracted claimed a link between autism and vaccines. Numerous scientific studies since then have proven that no such link exists.

“There’s a lot of fear based on widely-shared misinformation on social media,” said Michaud, whose organization represents doctors before the Legislature. “I hope the Legislature will consider bringing forward another bill next year.”

‘OUR PUBLIC HEALTH FABRIC IS BEING FRAYED’

After California experienced a measles outbreak in 2015, the state legislature approved a law imposing much more strict vaccination requirements. Since then, vaccination coverage among schoolchildren has improved substantially in California, according to the Los Angeles Times.

Maine State Rep. Ralph Tucker, D-Brunswick, sponsored a bill in 2015 that would have eliminated Maine’s philosophic exemption.

Tucker later agreed to support a measure that did not eliminate the exemption, but made it more difficult for parents to opt out by requiring the signature of a medical professional before parents could forgo vaccines for their children. That bill was approved by the House and Senate, but did not survive a LePage veto.

Tucker said he believes more strict vaccine requirements are necessary, but he’s unsure whether lawmakers will take up the bill next year because it’s unclear whether there would be enough support to override a veto.

Tucker said Maine may have to wait for a new governor, as LePage is termed out and his term ends in January 2019.

“What we’re looking for is results, not crusades,” Tucker said. “Right now, our public health fabric is being frayed.”

Joe Lawlor can be reached at 791-6376 or at:

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