I just read on Yahoo.com that the most germ infested places, studies show, in our homes are...
the refrigerator door handle
salt and pepper shakers
I must admit...I used to be in a great habit of wiping down the light switches and doorknobs w/ Lysol wipes quite regularly. However, I have not done it lately. So I would just encourage you to wipe down as many of these as you can as the winter is right around the door! =)