1 week after the flu shot, I developed severe joint pain in his shoulders, and a little back issue. Went to hospital and came back with a diagnosis polymyalgia rheumatica.; little itching; hives; joint pain; Like a rash or chemical reaction; This spontaneous case was reported by a physician and describes the occurrence of POLYMYALGIA RHEUMATICA (1 week after the flu shot, I developed severe joint pain in his shoulders, and a little back issue. Went to hospital and came back with a diagnosis polymyalgia rheumatica.) in an elderly male patient who received mRNA-1273 BIVALENT .222 (MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5)) for COVID-19 prophylaxis. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product INFLUENZA VACCINE (FLU [INFLUENZA VACCINE]) for an unknown indication.    No Medical History information was reported.   In September 2022, the patient received fifth dose of mRNA-1273 BIVALENT .222 (MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5)) (unknown route) 1 dosage form. In October 2022, the patient received dose of INFLUENZA VACCINE (FLU [INFLUENZA VACCINE]) (unknown route) 1 dosage form. In 2022, the patient experienced PRURITUS (little itching), URTICARIA (hives), ARTHRALGIA (joint pain) and RASH (Like a rash or chemical reaction). In October 2022, the patient experienced POLYMYALGIA RHEUMATICA (1 week after the flu shot, I developed severe joint pain in his shoulders, and a little back issue. Went to hospital and came back with a diagnosis polymyalgia rheumatica.) (seriousness criterion medically significant). The patient was treated with PREDNISONE ongoing since an unknown date at a dose of tapered dose, taking for 5 weeks. At the time of the report, POLYMYALGIA RHEUMATICA (1 week after the flu shot, I developed severe joint pain in his shoulders, and a little back issue. Went to hospital and came back with a diagnosis polymyalgia rheumatica.) had not resolved and PRURITUS (little itching), URTICARIA (hives), ARTHRALGIA (joint pain) and RASH (Like a rash or chemical reaction) had resolved.        For mRNA-1273 BIVALENT .222 (MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5)) (Unknown), the reporter did not provide any causality assessments.   No concomitant information was provided.  The patient was taking treatment medication as prednisone tapered dose currently (at the time of report), which patient had been taking for 5 weeks.  It was reported that received the omicron as a 5th booster in the right upper arm in September. Patient never had coronavirus prior to that at the end of September. Then a few days later patient developed a little itching, hives and joint pain. Like a rash or chemical reaction. Lasted 3-4 weeks. After that patient went home and received the flu shot in the left arm first week of October. 1 week after the flu shot, patient developed severe joint pain in the shoulders and a little back issue. The patient went to hospital and came back with a diagnosis polymyalgia rheumatica. The patient had been very active previously and not experienced anything like that and wanted to know if there were reports of polymyalgia rheumatica following the COVID-19 vaccine.   Company Comment: This is a spontaneous case concerning an elderly, male patient with no reported medical history and administration of the influenza vaccine, who experienced the serious (due to medically significant) unexpected, event of Polymyalgia rheumatica, which occurred after the mRNA-1273.222 (Original/Omicron BA.4/5) vaccine, received as the fifth dose of COVID-19 vaccination schedule. Patient reported a few days after vaccination he developed a little itching and hives and joint pain. Like a rash or chemical reaction that lasted 3-4 weeks. After that he received the flu shot in the left arm first week of October and 1 week after the flu shot, he developed severe joint pain in his shoulders, and a little back issue. Went to hospital and came back with a diagnosis polymyalgia rheumatica. Patient received prednisone. The outcome was reported as not recovered. The administration of influenza vaccine one week prior to onset of polymyalgia rheumatica symptoms, remains as a confounder. The benefit-risk relationship of mRNA-1273.222 (Original/Omicron BA.4/5) vaccine is not affected by this report.; Sender's Comments: Company Comment: This is a spontaneous case concerning an elderly, male patient with no reported medical history and administration of the influenza vaccine, who experienced the serious (due to medically significant) unexpected, event of Polymyalgia rheumatica, which occurred after the mRNA-1273.222 (Original/Omicron BA.4/5) vaccine, received as the fifth dose of COVID-19 vaccination schedule. Patient reported a few days after vaccination he developed a little itching and hives and joint pain. Like a rash or chemical reaction that lasted 3-4 weeks. After that he received the flu shot in the left arm first week of October and 1 week after the flu shot, he developed severe joint pain in his shoulders, and a little back issue. Went to hospital and came back with a diagnosis polymyalgia rheumatica. Patient received prednisone. The outcome was reported as not recovered. The administration of influenza vaccine one week prior to onset of polymyalgia rheumatica symptoms, remains as a confounder. The benefit-risk relationship of mRNA-1273.222 (Original/Omicron BA.4/5) vaccine is not affected by this report.