Found 2 thin foot long white string in stool. looks like dental floss or thin white noodle. is this a worm? what kind? is it from my cat?

Possibly a tapeworm: Intestinal worms are surprisingly common but seldom diagnosed. It sounds like you might have a tapeworm, which can be many feet long but come out in pieces. If you collect a piece your Dr. can send it to a lab for analysis.You can also get blood or saliva tests for antibodies to tapeworm. It could be from a cat.See http: //www.healthhype.com/human-intestinal-worms-symptoms-pictures-treatment.html