My husband had a sudden onset a couple of weeks ago. He was traveling and had to go to urgent care. Tested positive for Step A. Then it went into an upper respiratory illness. He received a steroid and antibiotic injection ( Rocephin) in urgent care and 10 days on Amoxicillin. Took him over 2 weeks to improve despite Gargles, sinus cleansing, peroxide and saline nebulizer treatments, taking all the good stuff for immune support. He was under increased stress due to family illness in another state. He took a flight out of town. May have gotten the secondary infection from the flights. It was a sudden onset of the strep throat.