If you ever had chicken pix, you "have shingles" right now.
Your immune system never fully fights off chicken pox. It fights it to a standstill and it goes away, but can't kill all of it so there is a little alive in you forever, under the immune systems boot.
If your immune system fails for any reason, you get Shingles because chicken pox is no longer suppressed, and without an immune system to fight it, it is worse than ever before.
If you ever had chicken pix, you "have shingles" right now.
Your immune system never fully fights off chicken pox. It fights it to a standstill and it goes away, but can't kill all of it so there is a little alive in you forever, under the immune systems boot.
If your immune system fails for any reason, you get Shingles because chicken pox is no longer suppressed, and without an immune system to fight it, it is worse than ever before.