vertical streaks on back of neck and upper back

[Guest guest]

Hi, my son has some thin vertical streaks across the top of his back. They are

dark red/purple. They are more along his shoulders and the back of his neck. I

first noticed two days ago, but I have been watching this closely and it seems

they are now spreading lower. Anyone seen anything like this before? It is a

first for us. Wondering if it is viral or bacterial related. He has not been

physically well for the past few days. Mostly allergy/sinus type symptoms. Only

a low grade fever in the 99's at most.

Kari