...that makes an unvaccinated person a criminal...

Think that is not that b/w, law predicts other forms of violation the rules that are not defined in terms of criminal; like when you are driving through the red light, you get money punishment and some dark spots in your driving folder but is not regarded as criminal activity although endangers the driver and other members of traffic.
And speaking about morality, well, relativity is main characteristic of moral, it depends on different variables; take as an example the trolley problem :)