lumbar stroke; general lethargy; paresthesia to mouth; lower extremity weakness; developed a droop to her mouth; the pads of her thumbs had begun to go numb/numbness in all her fingertips; paresthesia in her feet and limbs; getting worse and pain ( in lower extremities) was increasing; constipation; could not walk; stress; feeling fatigued; Based on additional information received on 10-Nov-2020, this case initially considered as non- valid non-serious was upgraded to valid serious.  Initial information was received on 09-Nov-2020 regarding an unsolicited valid serious case from a other health professional.  This case involves a 81-year-old female patient who experienced feeling fatigued (fatigue), could not walk (gait disturbance), stress, paresthesia in her feet and limbs (paraesthesia), getting worse and pain (in lower extremities) was increasing (pain in extremity), constipation, lumbar stroke (spinal stroke), droop to her mouth (facial paralysis) and the pads of her thumbs had begun to go numb/numbness in all her fingertips (hypoaesthesia), general lethargy (lethargy), paresthesia to mouth (paraesthesia oral) and lower extremity weakness (muscular weakness), while she received INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE [FLUZONE HIGH-DOSE QUADRIVALENT].  The patient's medical history included Haemangioma. Past medical treatment(s), vaccination(s), and family history were not provided. Concomitant vaccines none.  On 08-Sep-2020, the patient received a dose of 0.7 ml suspect INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE (strength-high dose, lot number and expiry date were not reported) via intramuscular route in unknown administration site for prophylactic vaccination.  On 26-Sep-2020, the patient developed serious feeling fatigued (fatigue) 18 days following the administration of INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE.  On 29-Sep-2020, the patient developed serious could not walk (gait disturbance) and stress, 21 days following the administration of INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE. The patient went to the local emergency department.  It was reported that the stress was associated with the cross-country move that she was in the mid-east of. At that point, she was able to ambulate, but required a walker to do so. Prior to this the patient had been extremely active. She played 18 holes of golf 4-5 times weekly, took part in water aerobics and pickleball, and did yoga daily.  On 08-Oct-2020, the patient developed serious paresthesia in her feet and limbs (paraesthesia), getting worse and pain in lower extremities was increasing (pain in extremity) and constipation 1 month following the administration of INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE.  The patient took into the emergency department again. After 7 hours, she was discharged with a diagnosis of constipation.  On 14-Oct-2020, the patient developed serious lumbar stroke (spinal stroke), droop to her mouth (facial paralysis) and the pads of her thumbs had begun to go numb/numbness in all her fingertips (hypoaesthesia) 1 month 6 days following the administration of INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE.  The event spinal stroke was assessed as medically significant.  On an unknown date, the patient developed serious general lethargy (lethargy), paresthesia to mouth (paraesthesia oral) and lower extremity weakness (muscular weakness) (unknown latency) following the administration of INFLUENZA QUADRIVAL A-B HIGH DOSE HV VACCINE.  The seriousness criteria was hospitalization for all the events.  On 16-Oct-2020, the patient was sent to the emergency department at the Clinic, where she was admitted. Patient remained in hospital for 3 weeks and was recently discharged to a rehabilitation facility.   Relevant laboratory test results included: On an unknown date: - Patient has not been given any definitive diagnosis, Magnetic resonance imaging (MRIs) show that her spine is inflamed. MRI, without conclusive diagnosis [inconclusive].  Corrective treatment was unknown.  At the time of report outcome was unknown for all the events.   Information on the batch number was requested.   Additional information was received on 10-Nov-2020 regarding a serious case by consumer (patient daughter).  Patient details, laboratory test and medical history added. Suspect drug updated. Previously coded adverse event was deleted, and new events added. Corresponding fields and narrative were updated accordingly.; Sender's Comments: Sanofi company comment as per follow up dated 10-Nov-2020: This case involves 81-year-old female patient who experienced fatigue, gait disturbance, stress, paraesthesia, pain in extremity, constipation, spinal stroke, facial paralysis, hypoaesthesia, lethargy, paraesthesia oral and muscular weakness after vaccination with FLUZONE HIGH-DOSE QUADRIVALENT. The time to onset is compatible. Magnetic resonance imaging (MRIs) show that her spine is inflamed. Further information regarding medical treatment, patient's health condition at time of vaccination and concomitant medications were not reported. Based upon the reported information the role of the suspect vaccine cannot be assessed.