A 15-year-old adolescent male comes to the clinic with his parents with a chief complaint of fever, nausea, vomiting, poorly localized abdominal pain, arthralgias, and swollen lymph nodes". States he has felt "lousy" for a couple of weeks. The fevers have been as high as 102 F. His parents thought he had the flu and took him to an Urgent Care Center. He was given Tamiflu® and sent home. He says the Tamiflu didn’t seem to work. States had a slight sore throat a couple of weeks ago and attributed it to the flu. A physical exam revealed a thin young man who appears to be uncomfortable but not acutely ill. Posterior pharynx reddened and tonsils 3+ without exudate. + anterior and posterior cervical lymphadenopathy. Tachycardic and a new onset 2/6 high-pitched, crescendo-decrescendo systolic ejection murmur auscultated at the left sternal border. Rapid strep +. The patient was diagnosed with acute rheumatic heart disease (RHD). Explain how a positive strep test has caused the patient’s symptoms.