I have suffered from emetophobia since I was about 12 (at least, that's when it was first an issue) and had a sv*. My therapist seems to think it developed throughout my childhood; my older brother had terrible problems with his tonsils and was constantly sick. He would v* often and randomly due to the swollen tonsils, and it took years before they finally removed them. This continued exposure made me feel terrified of being sick, because I knew it was a scary thing that I was trying to understand from a young age. I had a severe bought of anorexia for about a year in my teens due to the fact that I was terrified of being sick. Eventually, as most teenagers do, I recovered and worked my way out of the hole. I still suffered from anxiety when there was an outside "triggering event," but it wasn't anything crazy.
Now I am 26 and am still suffering from this terrible phobia. It has caused daily anxiety for me, but I think I'm starting to finally get it under control. I am terrified as the winter season creeps back upon us, but I am trying to work through my anxiety as best I can.