TULSA, Oklahoma - A new study released Friday morning shows more Oklahoma kids are going to school without vaccinations. Records show in the last eight years, the percentage of kindergartners whose parents have claimed an immunization exemption has doubled.

That includes vaccines for diseases like polio and measles.

Oklahoma law requires students have certain immunizations before starting school, but it also allows parents to claim certain exemptions.

That means parents don't have to get their kids vaccinated if it's on medical or religious grounds. Oklahoma is one of 19 states that allows an exemption for philosophical reasons too.

In the 2005-06 school year, .7 percent of parents claimed an exemption. In the 2013-14 year, that doubled to 1.4 percent.

In Tulsa, 502 students are on the exemption list right now.

Oklahoma already has a policy in place that once a case of the measles is reported in the state, the Commissioner of Health can and will exempt students from class who are not vaccinated.

"We've had kids with bone marrow transplants and with cancer, these kids who don't have their vaccines are putting those kids at risk. All it takes is one and we're going to have a problem," said Debbie Johnson, Registered Nurse and administrator at Oklahoma City Public Schools.

Across the state however, the number of students on the exemption list is quite low. The state is tied for the 17th lowest exemption rate in the country.