I recently commented on whether there should a cause of action against the parents of a child who do not vaccinate their children. See here. In that comment I wrote that "In California, . . . a bill is making its way through the system that would allow children to opt out of mandatory school vaccinations only if they have a medical condition that justifies an exemption. (NPR has the story here.) "
As an update to the issue, here is a link to an article in the New York Times on the bill in California.