SACRAMENTO (CN) - Citing 99 confirmed measles cases since December, two California state senators introduced legislation that would make it harder for parents to enroll unvaccinated children in school.
The bill would eliminate the "personal belief exemption" which permits parents to decline vaccinations for their children and enroll them in California public schools.
California is one of 20 states with such personal belief exemptions.
The vaccination bill was introduced Wednesday by state Sens. Richard Pan, D-Sacramento, and Ben Allen, D-Redondo Beach, and comes during California's worst measles outbreak in decades.
Of the 99 confirmed measles cases in California, 39 originated from people visiting Disneyland in December, according to the California Department of Public Health. Orange County, where the outbreak began, has seen the most cases with 31, and Los Angeles County next with 17.
"We are in a situation where there are not enough people being vaccinated to contain these dangerous diseases," Pan said.
Pan, a pediatrician, has introduced other vaccination bills including, AB 2109, which requires parents to consult with a licensed physician before submitting a personal belief exemption.
Pan's bill proved successful in its first year, as 2014 was the first year since 1998 that the opt-out rate declined, according to the Department of Public Health.
This school year 13,260 parents used the personal belief exemption in California.
"While I am pleased that more families are choosing to immunize their children and the statewide rates are going in the right direction, it is important to know that there are pockets of the state where the low vaccination rates continue to put children at risk," Pan said in a statement.
The bill would eliminate a parent's right to claim a personal belief exemption, but parents could choose another route to avoid vaccination via the religious belief exemption.
The measles outbreak has heightened the debate between scientists and parents who claim that vaccination can be linked to autism. Scientists say there is no such link.
New Jersey Gov. Chris Christie and Kentucky Sen. Rand Paul, both of whom are considering a run for the Republican presidential nomination, made headlines by supporting parents' right to refuse to vaccinate their children.
Leading politicians in California are wary.
"While a small number of children cannot be vaccinated due to an underlying medical condition, we believe there should be no such thing as a philosophical or personal-belief exemption, since everyone uses public spaces," Sens. Barbara Boxer and Dianne Feinstein wrote to California Health and Human Services Secretary Diana Dooley.
Gov. Jerry Brown indicated support for the bill as well.
Data from the present California outbreak shows that most measles cases have been adults. Just eight confirmed cases have been children younger than 1.
In 2000 the United States declared measles had been eliminated, proof that the vaccine was effective.
Before the first measles vaccines in 1963, 3 million to 4 million people got the disease every year in the United States, according to the Center for Disease Control and Prevention.
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