You work in a GP surgery and receive a telephone call from Mrs Jones who reports her 14 year old son, Toby, has come out in a widespread non-blanching red rash. She emails you an image of the rash and it looks maculopapular in nature. There is no history of headache, neck stiffness or vomiting. He was seen by your GP colleague 2 days ago with a sore throat and fever and was commenced on Amoxicillin.
What is the most likely pathogen behind his likely diagnosis?