Hey sarah, if you get toxo as an adult you get flu like symptoms (i think, am dredging up 3rd year uni stuff here) so you wouldn't know. It's not a problem for adults as the parasite forms little cyst like things in tissue notably the brain and then just sort of sits there. Because adult brains are fully formed it's not a problem but when brain tissue is forming as in a featus it is a huge problem. Upside - my DH has to do the cat litter to even though we are still trying. He HE HE