Back Pain; shoulder and hip pain/Polyarthralgia; Rash on his torso, Fever, joint pain and Rheumatic Fever 103.7F; This case was received via an unknown source (no reference has been entered for a health authority or license partner) on 30-Mar-2022 and was forwarded to Moderna on 30-Mar-2022.    This spontaneous case was reported by a consumer and describes the occurrence of BACK PAIN (Back Pain), ARTHRALGIA (shoulder and hip pain/Polyarthralgia) and RHEUMATIC FEVER (Rash on his torso, Fever, joint pain and Rheumatic Fever 103.7F) in a 20-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 030821B) for COVID-19 vaccination.     Previously administered products included for COVID-19 vaccination: J&J COVID-19 Vaccine in February 2021. Past adverse reactions to the above products included No adverse event with J&J COVID-19 Vaccine.    On 31-Dec-2021, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 21-Feb-2022, the patient experienced BACK PAIN (Back Pain) (seriousness criteria hospitalization and medically significant), ARTHRALGIA (shoulder and hip pain/Polyarthralgia) (seriousness criteria hospitalization and medically significant) and RHEUMATIC FEVER (Rash on his torso, Fever, joint pain and Rheumatic Fever 103.7F) (seriousness criteria hospitalization and medically significant). The patient was hospitalized on 21-Feb-2021 due to RHEUMATIC FEVER, then on 21-Feb-2022 due to ARTHRALGIA and BACK PAIN. At the time of the report, BACK PAIN (Back Pain), ARTHRALGIA (shoulder and hip pain/Polyarthralgia) and RHEUMATIC FEVER (Rash on his torso, Fever, joint pain and Rheumatic Fever 103.7F) had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Biopsy bone marrow: clear (normal) Biopsy of Bone Marrow came out clear.. On an unknown date, Blood test: negative (Negative) Blood test for pathogens came out negative. On an unknown date, Body temperature: 103.7 (High) 103.7F. On an unknown date, Electrocardiogram: normal (normal) normal. On an unknown date, Heart rate: high (High) High Heart Rate 200 BPM and high (High) another episode of High Heart rate. On an unknown date, Magnetic resonance imaging heart: normal (normal) normal.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   It was reported that, Patients Mother was calling to report that her 20-year-old son received a booster of Moderna COVID-19 vaccine and experienced adverse events that are continuing today.  First dose: J&J COVID-19 Vaccine on  FEB2021    after 3 weeks of moderns booster, the patient experienced the  reported events. He visited the Emergency Room and was admitted to the hospital on the same day. On 21FEB2022 he was Diagnosed with: Adverse Reaction to vaccine. He was released from the hospital after 5 days.  He was re-hospitalized on 28FEB2022. He was released after 5 days again It was reported that patient experienced rash on torso, fever, joint pain.  No concomitants were reported.         No treatment information was reported.  Company Comment: This spontaneous case concerns a 20-year-old male patient with no relevant medical history, who experienced the unexpected serious events of Back Pain, Arthralgia (shoulder and hip pain/Polyarthralgia) and Rheumatic fever that occurred 51 days after receiving the booster dose of mRNA-1273 Vaccine.  The events were medically significant and led to hospitalization. Patient initially presented with rash on his torso associated with back, shoulder and hip pain with heart rate of 200 beats per minute. He was then admitted and diagnosed with Rheumatic fever (Temperature of 103.7F) and Polyarthralgia and sent home five days later. Two days after discharge, patient was readmitted for another episode of high heart rate, joint pain and fever and eventually discharged after 5 days. Blood test for isolates and bone marrow biopsy were negative, EKG, and cardiac MRI were all normal.  Patient previously received a dose of J&J COVID-19 Vaccine on an unspecified date. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.; Sender's Comments: This spontaneous case concerns a 20-year-old male patient with no relevant medical history, who experienced the unexpected serious events of Back Pain, Arthralgia (shoulder and hip pain/Polyarthralgia) and Rheumatic fever that occurred 51 days after receiving the booster dose of mRNA-1273 Vaccine.  The events were medically significant and led to hospitalization. Patient initially presented with rash on his torso associated with back, shoulder and hip pain with heart rate of 200 beats per minute. He was then admitted and diagnosed with Rheumatic fever (Temperature of 103.7F) and Polyarthralgia and sent home five days later. Two days after discharge, patient was readmitted for another episode of high heart rate, joint pain and fever and eventually discharged after 5 days. Blood test for isolates and bone marrow biopsy were negative, EKG, and cardiac MRI were all normal.  Patient previously received a dose of J&J COVID-19 Vaccine on an unspecified date. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.