I disagree. The government SHOULD be able to force people to do things to be up to standard for the good of society. Attending a basic level of public education? Maintenance of hygiene? REASONABLE actions to prevent the spread of diseases? I believe a vaccine which has been scientifically proven to have a lower risk of death than the disease it prevents qualifies as such.

Contrast the above with a case of two lives in one package. An independently functional mother and an as yet unborn child. Is it reasonable to allow the mother to risk their own life (and endanger the linked child's life) in pursuit of some belief when that risk does not spread to others? That is a very different question than one which has an impact on risk to society as a whole.

I will say, if you support enforcing a particular outcome against 'parents rights' in this case, you had better also be for more state intervention and standards upkeep with respect to ensuring that child has sufficient resources and support to become a functioning member of society. If you're willing to go that far, then I can support the logical stance of extending said support even to the point of forcing the child out of their mother against the only individual who could consent or deny consent for that effort.