I think that where an individual's choices to not take preventative healthcare actions that are free, widely available and very well publicised and understood impact upon the ability to deliver essential care to others who did take those actions, it is reasonable to take actions that favour the one being disadvantaged.
Rights may be absolute but they can also be withheld. The right to liberty can be overridden by incarceration when someone has committed a suitably serious offense, in order to a) rehabilitate them and b) protect the rest of society from them. I don't see why a right to healthcare couldn't be equally restricted in order to protect the rest of society.