I'm wondering if you're actually reinfecting yourself?

I once got poision ivy from a dog at work. I didn't realize it until I'd already touched a gazzilion things in my car & house which is why I had a very hard time getting rid of it, I was reinfecting myself. I ended up having to launder or scrub down everything I'd touched, sat on, leaned on, the WORKS to get rid of the oils in the house. Once I'd cleaned everything it finally went away.

Poision ivy oils can live for years outdoors even on a dead plant, they are very persistent.