True . . .I had mumps, TWICE. I gave it to myself. One gland (of nine possible) on the right side of my neck. In isolation at home. About two weeks later, a gland on the left side of my neck swelled up. I gave it to myself.

Incidentally, I am old enough I never got the MMR vaccines. I had already had 4 cases of the 3 viruses before they came out with the vaccines.