The other side of that story is those who have claimed to have had severe tonsillitis or appendicitis at one time or another because they had a sore throat or some lower stomach cramps (i.e. some gas) but somehow thought they did but did not and never actually ever had either severe tonsillitis or appendicitis, and they actually survived their never non-life threatening condition. Surprise surprise!
Or maybe you had this guy as your doctor and you just got real lucky:
My pedi was trained at Johns Hopkins. He was from an era when kids died of real diseases. They kept an eye on my tonsillitis and sure enough, I outgrew it. He began practice before antibiotics. And told my mom that only in a few really bad cases did it mean anything other than sleepless nights for the mom.