Shhh everyone, it can hear you talking about it right now...
Just kidding, I don't get poison ivy, never did, but I also avoid it now for the most part because my wife gets it. In fact she's not even here with me but might be starting to itch because I'm even talking about it!! I usually take a machete and sever the stems along a tree trunk and take out a 2" or more section, if you just cut it, it can grow back. This causes it to die in the tree and I just leave it, over time in rots and falls out of the tree in pieces. I see it along the stone walls, that's harder to get rid of since its usually a network of smaller vines. Around here a lot of people confuse it with Virginia Creeper, a harmless vine that looks vaguely similar.
When I'm done for the day, and I think I may have been near it, I put my clothes in the machine by themselves with Tide/Era/etc. I don't let my wife touch them. I then go wash with either Dawn or I find "Lava" soap works just as good, it takes all the oil off your skin.
I just cant ever think of a time I ever had a reaction to it, and I used to grab it with my bare hands and pull it out of trees and not wash for hours afterwards, never an issue. A coworker and her family would get it bad, and easily. One year we were talking about it and she described this dead tree in the yard that poison ivy had choked out the top of the tree. The tree died and the poison ivy kept using the this tree, more like a topless trunk, to start spreading out to other trees. They kept a 20 foot radius clear of the tree in fear that they would get it. It looked like a fuzzy caterpillar standing on end it was so covered with PI. I went there on a Saturday, cut the tree down, cut into rounds, loaded it into the pickup, and unloaded at the local transfer station. The attendant had me unload it in a different pile than the rest of the brush. I went home a couple hours later, showered with Lava soap and never got anything. Monday I saw her, and she said her mind had her feeling itchy all weekend!!
But I also don't usually get a reaction from mosquito bites. If I get any lump or redness it's gone within an hour. Deer fly bites usually itch for a little bit then go away. Ant bites & bee/wasp stings usually hurt then itch for a couple days, ice helps the swelling. Speaking of which I don't think I'd try ice on poison ivy, it may help the immediate itch, but I could see the water diluting and spreading the oils making it eventually worse.