In the Nursery
As you may have suspected, pre-toilet trained children and their parents are a lot more likely to come in contact with germs during diaper changes. Taking extra care to wash your hands after diaper changes, especially before touching children or serving food, can help keep such germs from spreading. Changing table covers and pads should be switched out often and washed in hot water, preferably with detergents that contain germicides.
Another precaution that might limit germ exposure is regular cleaning of toys and other objects your kids touch repeatedly. Usually, a nontoxic cleanser like soap and water or hydrogen peroxide does the trick. Baby wipes with alcohol or a bleach and water solution may also be used in cases where soap and water aren't handy, if the toys are especially dirty or have an odor (be sure to rinse thoroughly in these cases).