The patient was still shaking a bit; COVID; She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine; She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine; This spontaneous case was reported by a consumer and describes the occurrence of TREMOR (The patient was still shaking a bit), COVID-19 (COVID), INTERCHANGE OF VACCINE PRODUCTS (She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine) and COVID-19 IMMUNISATION (She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine) in a 76-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.  The patient's past medical history included Unspecified disease of respiratory system. Previously administered products included for Product used for unknown indication: Pfizer (Dose 1, Lot: EL9253) on 30-Jan-2021, Pfizer (Dose 2 andLot: GL9267) on 21-Feb-2021. Past adverse reactions to the above products included No adverse event with Pfizer and Pfizer. Concurrent medical conditions included Diabetic (endocrine abnormalities (including diabetes)), Rheumatoid arthritis (diagnosed about 26 years ago), Immunocompromised, Allergy NOS, Chromosomal abnormality NOS and Obesity. Concomitant products included ABATACEPT (ORENCIA) for Immunocompromised.  In December 2021, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. In December 2021, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine) and COVID-19 IMMUNISATION (She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine). On 16-Mar-2022, the patient experienced COVID-19 (COVID). On an unknown date, the patient experienced TREMOR (The patient was still shaking a bit). At the time of the report, TREMOR (The patient was still shaking a bit) had not resolved and COVID-19 (COVID), INTERCHANGE OF VACCINE PRODUCTS (She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine) and COVID-19 IMMUNISATION (She had first two doses of Pfizer and Booster dose of Moderna Covid-19 vaccine) outcome was unknown.    The age of patient was reported as 76 years 3 months. It was reported that patient was over 75 when she received the vaccines. On an unknown date in Dec-2021, the patient received third booster of Moderna COVID-19. On 16-Mar-2022, the patient had Covid. The patient was still shaking a bit. The patient administered flu vaccines on same date of the Pfizer Suspect. On 10-Sep-2022, at 15:00 PM the patient took fourth dose of Pfizer Bivalent vaccine, Anatomical Location was Left upper arm, batch number was GJ5342. The patient got the Bivalent Pfizer Covid booster along side flu shot few days ago and running high grade fever ever since. The fever was dropping off and the patient was sitting in a quiet room and sweating and not down to normal and was able to have coherent thoughts again. No treatment medications were reported.  Company Comment: This spontaneous case concerning a 76 year old female patient with relevant medical history of Diabetes, Rheumatoid arthritis , Immunocompromised with concomitant product of ABATACEPT ( Orencia ) and Obesity. This patient received initially two doses of Covid 19 vaccine Pfizer as primary series with no reported adverse events and  Pfizer Bivalent Covid 19  as booster dose together with flu vaccine . This patient experienced non-serious , unexpected, AESI of Covid 19 which occurred approximately 3 months post vaccination with the third dose of Covid 19 vaccine . This was accompanied by another non-serious , unexpected event of tremor which occurred on an unknown date with vaccination with the third dose of mRNA-1273 vaccine.  Non-serious , unexpected events of Interchange of Vaccine Products and Covid 19 Immunization ( Re-vaccination with a different Covid 19 vaccine ) also occurred  The details surrounding the events like treatment information , medical consultation or  if any laboratories /diagnostic procedures done were not reported. Outcome of the events was unknown.The current Covid-19 pandemic remain confounder for the event Covid-19. The concurrent medical condition of diabetes mellitus, age  and the concomitant use of immunosuppresant remain confounders for the immune response to mRNA-1273 vaccine. The benefit -risk relationship of mRNA -1273 ( Moderna Covid 19 Vaccine) is not affected by this report.   Reporter did not allow further contact.; Sender's Comments: This spontaneous case concerning a 76 year old female patient with relevant medical history of Diabetes, Rheumatoid arthritis , Immunocompromised with concomitant product of ABATACEPT ( Orencia ) and Obesity. This patient received initially two doses of Covid 19 vaccine Pfizer as primary series with no reported adverse events and  Pfizer Bivalent Covid 19  as booster dose together with flu vaccine . This patient experienced non-serious , unexpected, AESI of Covid 19 which occurred approximately 3 months post vaccination with the third dose of Covid 19 vaccine . This was accompanied by another non-serious , unexpected event of tremor which occurred on an unknown date with vaccination with the third dose of mRNA-1273 vaccine.  Non-serious , unexpected events of Interchange of Vaccine Products and Covid 19 Immunization ( Re-vaccination with a different Covid 19 vaccine ) also occurred  The details surrounding the events like treatment information , medical consultation or  if any laboratories /diagnostic procedures done were not reported. Outcome of the events was unknown.The current Covid-19 pandemic remain confounder for the event Covid-19. The concurrent medical condition of diabetes mellitus, age  and the concomitant use of immunosuppresant remain confounders for the immune response to mRNA-1273 vaccine. The benefit -risk relationship of mRNA -1273 ( Moderna Covid 19 Vaccine) is not affected by this report.