I got yelled at something fierce when I told a group how I made myself not allergic. They said I'd make people die and sue me. But I didn't catch poison ivy/oak after I read in a Euell Gibbons' book how to eat (!!) the tiny first leaves, so red and shiny, in the spring. One a day for a week. Like, really tiny, 1/4 an inch. I balled them inside a bit of Wonderbread, like a pill. gulp. Never had a problem with the stuff again.
This is NOT medical advice!!!! Do not do this unless you're fearless and will not sue me, either!!! Maybe I'm a fool for even mentioning this!
Vaccine is old germs, no?
Owell.