This is a spontaneous report received from contactable reporter(s) (Consumer or other non-HCP) from medical information team, Program ID:  A female patient received BNT162b2, BNT162b2 omi ba.4-5 (BNT162B2, BNT162B2 OMI BA.4-5), on 03Nov2022 as dose 5 (booster), single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Bnt162b2 (Dose 1, Single), for COVID-19 Immunization, reaction(s): "a little headache", "a achy"; Bnt162b2 (Dose 2, Single), for COVID-19 Immunization, reaction(s): "a little headache", "a little headache", "a achy"; Bnt162b2 (Dose 3, Single), for COVID-19 Immunization, reaction(s): "a achy"; Bnt162b2 (Dose 4, Single), administration date: Jul2022, for COVID-19 Immunization, reaction(s): "a little headache", "a achy". The following information was reported: AMNESIA (non-serious) with onset 04Nov2022, outcome "recovered" (Nov2022), described as "experienced memory loss describing it as early onset alzheimer's/next morning with some memory loss"; SOMNOLENCE (non-serious) with onset Nov2022, outcome "unknown", described as "a little groggy"; ANAEMIA (non-serious) with onset Nov2022, outcome "unknown", described as "diagnosed with global transient anemia due to the violent reaction that she had to the vaccine"; DEMENTIA ALZHEIMER'S TYPE (medically significant) with onset Nov2022, outcome "unknown", described as "experienced memory loss describing it as early onset alzheimer's"; SEIZURE (medically significant), CHILLS (non-serious), TREMOR (non-serious) all with onset Nov2022, outcome "unknown" and all described as "shivering and shaking and almost convulsing."; LETHARGY (non-serious) with onset Nov2022, outcome "unknown", described as "went back to sleep and slept until noon, which is 4 hours longer than her normal schedule". The events "experienced memory loss describing it as early onset alzheimer's", "diagnosed with global transient anemia due to the violent reaction that she had to the vaccine", "a little groggy", "shivering and shaking and almost convulsing.", "went back to sleep and slept until noon, which is 4 hours longer than her normal schedule" and "experienced memory loss describing it as early onset alzheimer's/next morning with some memory loss" required emergency room visit. The patient underwent the following laboratory tests and procedures: Blood test: (Nov2022) Unknown results, notes: Caller stated his wife went to the ER and had an MRI, CT scan, blood work and urine and nothing was wrong; Computerised tomogram: (Nov2022) Unknown results, notes: Caller stated his wife went to the ER and had an MRI, CT scan, blood work and urine and nothing was wrong; Magnetic resonance imaging: (Nov2022) Unknown results, notes: Caller stated his wife went to the ER and had an MRI, CT scan, blood work and urine and nothing was wrong; Urine analysis: (Nov2022) Unknown results, notes: Caller stated his wife went to the ER and had an MRI, CT scan, blood work and urine and nothing was wrong.  Clinical course: He was calling on behalf of his wife who had the 5 COVID-19 vaccines. The first 4 times she had minor reactions and the last time she had the Bivalent booster, he had a very negative reaction and woke up the next morning with some memory loss and he was wondering if thats anything the is calling on behalf of his wife who had the 5 COVID -19 vaccines. The first 4 times she had minor reactions and the last time she had the Bivalent booster, he had a very negative reaction and woke up the next morning with some memory loss and he was wondering if thats anything that we have had reported on in previous cases. that we have been had reported on in previous cases. His wife had the 4th Pfizer shot mid Jul and received the bivalent booster on 03Nov2022. she only was an achy and had a little headache after the previous vaccines. after the 5th vaccine she was a little groggy and experienced some of the same things from the previous vaccines. In the middle of the night, around 2:30 AM to 3 AM, she was shivering and shaking and almost convulsing. she woke up at 8 AM and was warm because she had put clothes on and went back to sleep and slept until noon, which is 4 hours longer than her normal schedule. she had no recollection of getting the booster, experienced memory loss describing it as early onset Alzheimers. she knew who her husband was but did not remember that her daughter is getting married or that her mother had passed away. his wife went to the ER and had an MRI, CT scan, blood work and urine and nothing was wrong. by 12 AM she was starting to come back and at 2 AM she had her memory back and now has minor lapses but is pretty much back to herself. she was diagnosed with global transient anemia due to the violent reaction that she had to the vaccine. Caller declined to be transferred because he said his wife worked in the pharmaceutical industry for 30 years and did a project with Pfizer and his wife wants to be involved in the reporting, but she was unavailable at the time. Caller stated his wife will call back to make a report.  The information on the batch/lot number for BNT162b2, BNT162b2 omi ba.4-5 has been requested and will be submitted if and when received.