I think if it's just a cold with no other symptoms, you can't exclude them. It just goes with the country we live in and colder winters.

Check the back of the Lysol wipes package to see how long it product has to be in contract with the surface to be effective. I don't use the wipes simply because I find it less expensive to have a sink/bucket of hot water and disinfectant for wiping hard surface and I submerge toys in the solution and let them air dry. Sounds like you are doing what you should, I'd just check the product information about use.