Chickenpox has been studied extensively over time. Chickenpox always begins on the chest, abdomen, or back if it is naturally acquired and the patient has not been immunized. The rash begins 10 to 21 days after the exposure and clearly follows a characteristic pattern. Remember chickenpox begins as red bumps which quickly become fluid-filled bumps in the first couple of days, and then crust over within a week. You will, therefore, know over a 24-48 hour period whether, in fact, it is chickenpox. It is easy to confuse chicken pox with insect bites, a reaction of the skin to something it came in contact with, or other causes of rash. Bumps on exposed areas of the body, such as the extremities, thus makes the diagnosis unlikely in this case. If there is any question about the rash, I would contact your child's physician. Otherwise, I would treat supportively -- trimming their nails so that they do not scratch it and become infected. Use small amounts of benadryl by mouth for any uncomfortable itching, and watch for the spread or the development of other symptoms.