The woman's flow of blood makes her unclean and by scripture, unfit for worship with God's people. She is to be avoided. Her touch renders Jesus unclean according to scripture. And according to scripture, contact with the dead makes him unclean, unfit for worship with God's people. The Pharisees and those like them presume that when the sacred touches the profane, it becomes profane.
Impurity always conquers purity.
These stories tell us Jesus practices the opposite. In Jesus, when the profane touches the sacred, it becomes sacred. Purity conquers impurity. But the people of Jesus' day had reason to fear impurity. Long ago before people understood anything about infection, these social bans were necessary to public health.