Believe it or not,.....I often get PI in the winter....yep.......because I'm too forgetful to wear gloves when I'm digging/transplanting a small tree or shrub from the property....and PI roots or suckers (which can run laterally....away from the visible "above-ground" stem....up to many feet away) are interwoven with the roots of other plants - including the one I'm transplanting. dopey me!
You may have contacted some that way...