Woke up nauseated with full blown vertigo; Hasn't eaten today; Woke up nauseated with full blown vertigo; Very unbalanced; Deafness; Vomiting; Woke with chills; Low grade temperature about 100F; Some soreness; This spontaneous case was received on 08-Sep-2020 from other non-health professional (consumer) via Agency (reference number: SEQW20-01337) and concerned a 72-year-old male patient.  The patient's medical history and concomitant medications were not reported.  On 05-Sep-2020 at about 3pm, the patient was vaccinated with Fluad Quadrivalent [influenza vaccine, inactivated influenza virus surface antigen (subunit), egg-derived, MF59; anatomical location: left deltoid, dose: 0.5 ml, route of administration: not reported] for an influenza prophylaxis. The batch number reported was 279786 and expiry date was 31-Aug-2020.  On the same day, after receiving Fluad Quadrivalent, the patient experienced some soreness.  On 06-Sep-2020 at 2am, one day after receiving Fluad Quadrivalent, the patient woke up with chills. During the day, the patient ran a low grade temperature about 100F for a few hours and had some vomiting.  On 07-Sep-2020, two days after receiving Fluad Quadrivalent, the patient was unbalanced and reported deafness and stated not total deafness but almost.  On 08-Sep-2020, three days after receiving Fluad Quadrivalent, the patient woke up nauseated with full blown vertigo and had to lay down. The patient was very unbalanced and hadn't eaten while deafness remained. The patient contacted medical doctor (MD) and they set him up for Covid test tomorrow at 2pm and prescribed nausea medication. The nausea has passed and he has now had a bowel movement (BM) and that has helped.  On 06-Sep-2020, the patient recovered from the events of chills, fever and vomiting.  On 08-Sep-2020, the patient recovered from the event of nauseated.  At the time of initial reporting on 08-Sep-2020, the patient had not recovered from the events of 'deafness' and 'balance disorder'.  The outcome for the events of pain', vertigo' and decreased appetite' were not reported.  The reporter did not provide causality assessment to Fluad Quadrivalent vaccine.  The reporter assessed the events as serious.  Company comment: Balance disorder, deafness, pain, vertigo, decreased appetite, pyrexia, vomiting, chills and nausea was associated with the use of the suspect product Fluad Quadrivalent. Pain occurred the same day after receiving the vaccine making chronology suggestive while for other events is assessed as plausible since they developed in the following days. The patient's medical history and concomitant medications were not reported however, there was a suspicion on COVID infection, but this was not confirmed. With information presented, causality is assessed as possibly related for pain, vertigo, decreased appetite, pyrexia, vomiting, chills and nausea due to plausible temporal relationship and lack of confounding factors. The patient's advanced age may provide some explanation for deafness making this event unlikely related to the vaccine. More information is needed for more precise causality assessment. (''unlikely related'' defaults to "related" in the safety database for reporting purposes); Sender's Comments: Balance disorder, deafness, pain, vertigo, decreased appetite, pyrexia, vomiting, chills and nausea was associated with the use of the suspect product Fluad Quadrivalent. Pain occurred the same day after receiving the vaccine making chronology suggestive while for other events is assessed as plausible since they developed in the following days. The patient's medical history and concomitant medications were not reported however, there was a suspicion on COVID infection, but this was not confirmed. With information presented, causality is assessed as possibly related for pain, vertigo, decreased appetite, pyrexia, vomiting, chills and nausea due to plausible temporal relationship and lack of confounding factors. The patient's advanced age may provide some explanation for deafness making this event unlikely related to the vaccine. More information is needed for more precise causality assessment. (''unlikely related'' defaults to "related" in the safety database for reporting purposes)