My grandson had a fever for several days around Christmas time but has been fever free for about 3 or 4 days. Last night he developed a minor rash on the inside of his thighs and on lower abdomen. He flew home to Florida this morning and my son called and said that he had a terriible dry cough and has the rash all over his body but not fever, What can it be? They are not in the area where he has a primary care physician. Should they take him to a doc in a box?