SEBASTOPOL (KPIX 5) — Parents opposed to vaccines are getting around a tough, new law.

California got rid of the personal belief excuse for school vaccinations, but parents may have found another way.

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A new study in the Journal of the American Medical Association shows a sharp spike in medical exemptions for incoming kindergartners from 2015 to 2016.

The total number of exemptions did go down, but it’s a sign, the law may not be working as hoped.

In Sebastopol, one school is concerned about the high number of students opting out.

Sebastopol Charter School principal Chris Topham has seen those numbers spike in his newest set of students.

Topham said, “We had 30 percent, maybe even 40 per cent of our kindergarteners with the medical exemption.”

The choice is ultimately up to the parents, Topham says, and he respects that.

But that unvaccinated percentage doesn’t come without its concerns.

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He and his staff have spent days working solely on vaccination paperwork to make sure they are compliant with state laws.

And there is always the threat of an outbreak that may put his students in danger.

“My concern is a worst case scenario, if we had an outbreak of say measles, is that we have a high number of children unvaccinated which puts them more at risk and we may have to close school for a while,” he said.

Medical ethicist Dr. Bill Anderick says that’s a valid concern.

“As a member of society we have a responsibility to that society and that is to participate in the general immunity of our population. To avoid that, to not perform in that way, violates our obligations to society,” Anderick said.

The other concern, he says, is ethical.

Anderick says doctors need to be giving exemptions for real medical reasons, not parental concerns, and that anything else should be investigated by the state’s medical board.

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“Clearly patients who have immunodeficiency syndrome would be harmed by a vaccine and it would be ethically inappropriate to vaccinate them. However, to lie and report such an immunity in order to avoid their responsibility to the culture is wrong. Ethically wrong and fraudulent,” Anderick said.