Suggest Treatment For Itchy Rash On Inner Elbow

Hello. A week ago I noticed an itchy rash on my inner elbows. The rash appeared to look like very small ant bites, or goosebumps and were red in appearance. The following day I awoke with extreme flu-like symptoms - high fever, migraines, joint paint, vomiting and fatigue. Over this past week the rash has quickly, and still continues to spread over my body, affecting my entire arms, abdomen, thighs and calves. My fever broke several days ago, yet the rash is still running rampant. I'm completely perplexed! I would greatly appreciate any help. Thank you in advance.