Can you diagnose me???

If you click on these pictures you may be able to see that Brianna has a lovely rash all over her body. We know it's contagious because her buddy Evan has it and Brayden's friend Sophi is getting it as well. It's not chicken pox - but we're just not sure what to call it! I don't feel well today either - my body aches and my stomach isn't quite right - however no rash for me! Any thoughts on what this may be???
Thankfully Brayden and Gary seem ok so far (but who knows how long that will last). Here is a picture of Brayden showing you his "skills"!!!