If you’ve had chicken pox you still have the virus lying dormant in your spine

If you’ve had Chicken Pox as a child the Varicella-Zoster virus lies forever dormant in your spine nerves, waiting for your immune system to fail so it can come back as Shingles. (But if you haven’t had it as a child then you better hope you don’t get it as an adult because it can be fatal)

http://www.umm.edu/health/medical/altmed/condition/varicellazoster-virus