Vaccines are growing topic for legislation — and advocacy — at the Capitol

State Sen. Ervin Yen has no plans of backing down.

Last year, the Oklahoma City lawmaker pushed, unsuccessfully, for legislation that would remove non-medical exemptions as an option for parents to give for not vaccinating their children.

"If I fail this session, I'll keep doing it until we get it passed, and we will get it passed — but I hope it doesn't take a big outbreak where lots of kids die," Yen said. "I'd like to get it passed before that happens."

Oklahoma is one of 18 states that allow philosophical exemptions for those who object to immunizations because of personal, moral or other beliefs, according to the National Conference of State Legislatures.