Gee, I guess I'm the 10% that never has had them.
I used to get them all of the time as a child, now I can hardly remember the last time I had one...yet I went for testing in August due to exposure to Hep B/C, the Dr tested for all STD's - and Herpes Simplex 1 still showed up as a positive for me! Fortunately it was the only thing I tested positive for! I do think, Shay, some families are more prone than others-although my 2 sons have yet to get one (19 yo and 14 yo).
It's hard to keep it to one party in the household - usually it'll get passed amongst siblings. Now that we're older, my bro and oldest sister still get them when they're stressed. Their children get them frequently.
My middle sis and me - we don't get them anymore, although it's in our blood - and our children have never had one.
Weirdest virus around if you ask me!