flared up a severe inflammation of her Hashimotos; flared up a severe inflammation of her Hashimotos; left arm started aching, then the achiness moved to her body; muscles were contracting; not able to sleep; no endurance; gained weight; brain is foggy; whole body just seized up; tremors; began to sweat; teeth chattering, shivering, chills; muscle in my chest kept popping; flu symptoms; Initial information received on 11-Nov-2019 regarding an unsolicited valid serious case received from a consumer.  This case involves a 73 years old female patient who experienced left arm aching, then the achiness moved to her body (pain) ,flared up severe inflammation of her hashimotos (autoimmune thyroiditis) with (condition aggravated),  muscles were contracting (muscle contractions involuntary) , not able to sleep (initial insomnia) , no endurance (exercise tolerance decreased) , gained weight (weight increased) , brain is foggy (feeling abnormal) , whole body just seized up (musculoskeletal stiffness) , tremors (tremor) , began to sweat (hyperhidrosis) and teeth chattering, shivering, chills (chills), flu symptoms (Flu like symptoms) and muscle in chest kept popping (chest discomfort) while she received vaccine INFLUENZA USP TRIVAL A-B HIGH DOSE SUBVIRION VACCINE [FLUZONE HIGH DOSE].  The patient's past medical history, medical treatment(s), vaccination(s) and family history were not provided. At the time of the event, the patient had ongoing Hashimotos. The patient did not received other vaccines.   On an unknown date (reported as between 04 Oct-2019 to 06-Oct-2019), the patient received a dose of suspect INFLUENZA USP TRIVAL A-B HIGH DOSE SUBVIRION VACCINE (lot UJ232AA and Exp. Date 10- Apr-2020) via unknown route in the left upper arm.  On an unknown date, the patient experienced flared up a severe inflammation of her hashimotos (autoimmune thyroiditis) with (condition aggravated), left arm aching, then the achiness moved to her body (pain) ,muscles were contracting (muscle contractions involuntary) , not able to sleep (initial insomnia) , no endurance (exercise tolerance decreased) , gained weight (weight increased) , brain is foggy (feeling abnormal) , whole body just seized up (musculoskeletal stiffness) , tremors (tremor) , began to sweat (hyperhidrosis) and teeth chattering, shivering, chills (chills), symptoms (Flu like symptoms) and muscle in chest kept popping (chest discomfort) (Unknown latency) following the administration of INFLUENZA USP TRIVAL A-B HIGH DOSE SUBVIRION VACCINE. This event was assessed as medically significant.  It was reported that, after vaccination evening, around 9pm, her left arm started aching, then the achiness moved to her body and she developed chills. Shivering and "flu symptoms" had subsided. It took her about a week to get back to feeling better. She stated that this episode, flared up a severe inflammation of her Hashimotos. She had no endurance, had gained weight and her brain is foggy. She stated that she has intermittent better and worse days, stating, "None are good." She has not followed up with her Hashimotos doctor because she has not been able to find a good Hashimotos doctor. She stated that she was going to follow up with her general practitioner.  Relevant laboratory test results included: On an unknown date body temperature was between 100-100.5 and was 102 after some time.  Final diagnosis was hashimoto's disease with aggravated condition.  The patient was treated with IBUPROFEN (IBUPROFEN) for chills and increase body temperature.  At the time of reporting, the patient was recovering from flu like symptoms, teeth chattering, shivering, chills and recovered on an unknown date from initial insomnia and tremors. For rest all events outcome was not reported.; Sender's Comments: This case concerns a 73 years old female patient who presented with hashimoto's disease (aggravated), pain, muscle contractions involuntary, initial insomnia, exercise tolerance decreased, weight increased, feeling abnormal, musculoskeletal stiffness, tremor, hyperhidrosis and chills after vaccination with INFLUENZA USP TRIVAL A-B HIGH DOSE SUBVIRION VACCINE [FLUZONE HIGH DOSE]. The time to onset is unknown. The patient had history of Hashimoto's disease. However, lab tests ruling out alternate etiologies were not reported. Based upon the reported information, the role of vaccine cannot be assessed.