Welcome Daniel. I did not have the "disadvantage" you have by not knowing for sure. I was promised a bike for my sixth birthday and was in the hospital. My dad answered my question of where my bike was by telling me I was not going to get a bike but braces instead. I know I had it and never did get my bike. But life has thrown me some great things my way also that probably would not have taken place. It must be frustrating to not know your medical history and be blindsided by the unknown. I have read it is very possible many had non-paralytic polio that was diagnosed as a summer flu. There is a vast amount of experience and information available here.