Unless of course it becomes a condition of medicare rebate, which is likely. As an un-vaccinated person is more costly to society as a whole.
But so are smokers, the obese, the disabled, people from low socio economic backgrounds and someone with a rare genetic disorder. There are also people who can't be vaccinated as well. If you want a collectivist health care system that means everyone is in it not just those who are more cost effective. The alternative is to abolish Medicare and go to a health insurance system where you get the health care you can afford.