A good way to make sure that viruses and bacteria are not continually reintroduced to a child is to sanitize the toys. There are commercial sanitizing mixes sold commercially, but an inexpensive way to clean toys is to soak them in a solution of bleach and water. According to the Clorox website, wash, wipe or rinse toys with water then soak in a solution of 3/4 cup Clorox Regular Bleach per gallon of water for 5 minutes. Rinse, then let air dry overnight in the sink.
If you have just a few toys, you can also just boil them for a few minutes in a pot on the stove, just as if you were sanitizing bottles.
The dishwasher is another great place to clean toys. While most parents lower the water temperature on their hot water tank, as long as the temperature is above 120°F, it will safely clean toys and dishes. Just be sure to place plastic toys in the top rack.
Fabric toys can be washed with simple soap and water and you can spray Lysol or another disenfectant on a cloth and wipe down toys with electronics.
Don't forget other places where your child places his mouth, either- such as crib rails and climbing toys or other large toys.
Beyond these cleaning measures, the most important thing to encourage in your household is hand washing. The average child has up to six colds a year, but regular hand washing can cut that in half. Have your children clean their hands before playing with toys to help keep germs from transferring. It's a simple way to get your children involved in their own health, and it's likely to make a big difference.
Because of Sam's current virus, as of yesterday, I am sanitizing the toys that Sam has played with that day nightly after he goes to bed. I'm going to buy a few spray bottles so that we can have the solution handy and not have to make a huge batch to clean the toys weekly (at least).