“In reaction to the outbreak, politicians in many states proposed bills tightening exemptions from school immunization requirements.[10] This short article examines the law and legislative trends in this area.

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Several states have exemption rates that are too high to preserve herd immunity. Oregon, at 7.1%, is at a high risk.[42] California has a low rate of exemptions overall, but has areas where rates of immunization are low.[43]Maine, Michigan, and Washington all have high exemption rates.[44] These states all face a real risk of disease. At least tightening these exemptions is a powerful idea.

Religious exemptions are completely inappropriate due to their vulnerability to abuse and the unfairness of putting the child at risk for beliefs the parents hold and the child is too young to choose. On the other hand, however, a system that does not leave parents any way to refuse vaccination is too extreme.

At the very least, since the public health argument is not as strong for homeschoolers, it makes sense to exempt children who are homeschooled from immunization requirements. Offering a hard-to-get personal belief exemption is preferable to a religious exemption, but should be harder to obtain than even the educational requirement currently in place.  Ideally, getting the exemption would require a daylong course with a short quiz at its end. The course requirement would help limit exemptions to only the very small set of parents with the strongest feelings against vaccines, parents who believe that asking them to vaccinate is akin to asking them to poison their child.”

http://wakeforestlawreview.com/2015/03/vaccines-measles-and-rights/