I have pityriasis rosea. It started with the christmas tree rash on my back. A week later it spread to my upper left arm. I went to urgent care. The rash has spread down my arms on both sides. Now there is small blisters inside the small rashes. I am 72 years old. My daughter had this a few years ago and said it lasted from 6 to 12 weeks. My neighbor across the way says that he and his son 6 years old just went to the dr today and he said its a virus. Wondering if ours is the same thing.