Gi infections are pretty common.You mean you have never ever in your life had the "stomach flu" or food poisoning. I don't know that it has to be a "bad infection" just an "infection" (By Bad you mean?? Had to be on antibiotics, got tossed in the hospital....from what I gather it can be the run of the mill GI infections people have and get over by themselves without intervention in a few days)Wow, you are lucky. I usually get a bout of one or the other every few years. I didn't know there were people who never had the "stomach flu" ever in their life. I thought everyone got this fairly regularly. And if I remember high school and college, being out a couple of days with the "stomach flu" was pretty common, and those viruses can tear through a dorm pretty easily.In studies going over medical records (in England where the records are searchable like that) people who had a GI infection are 4-20X more likely to get IBS in the year follow up than people who did not have a GI infection.It actually seems to be a pretty common way to get IBS started off, not a rare way.It probably isn't everyone, and it doesn't seem every IBSer has the bacterial overgrowth thing also, even in Post Infectious IBS.K.