What Causes Rash Extending From Collar Bone To Breast?

i have a rash extending from my right collar bone down on to the top of my breast. small red dots. they don t itch all the time, very rare for the most part and i have had them for at least four days now. i have had shingles in the past but i wanted to make sure it wasn t scabies seeing that i work in a juvenile hall. my head and throat have been hurting as well as my right ear and i thought it might be a bad ear infection.