J.S.
Why would you imagine the oil is very much in your house. Like no one ever thought that until you. Several weeks and no one has got a rash, heck even your husband didn't know it was poison ivy, not sure what make you now discover it was poison ivy. Even if it was poison ivy he may have not come in contact with the oil and even if he did it would have washed off quickly.
I guess I am saying you sound like a victim of google diagnosis, not a good thing.
By the way I am not even allergic to poison ivy, like I can pick it, brush against it and no rash. We went out to the country and whacked the heck out of poison ivy so that the side of the car was gooey. I got a rash because it was so concentrated, washed right off the car, no one else was harmed.