I developed a redness on half of my neck going down and including my trunk - mostly upper chest and entire back.  A day later a rash appeared with much itching.  The itching continues although the rash is diminishing.  Now on my upper back an area about the size of a nickel has developed as a fluid filled blister and there are two areas on my wrist - the inside and outside like two inch wide stripes with no discomfort.  The itching continues on my trunk.  This is baffling.  All began about two weeks ago.  I feel well.