Some parents refuse to
have their children vaccinated. Should these parents be forced to
vaccinate their children in order to protect the rest of society against
the reemergence of killers, such as polio?
Ok but the same arguments apply. Why is the person not vaccinating: ignorance, mistrust, lack of time, too far or too inconvenient? Would some monetary inducement help? Again the reasons and concerns must be dealt with. You cannot force people to vaccinate unless it is an emergency sotuation: the carrot is normally more successful than the stick.