Baker's cysts behind knee caps; head to toe body rash and hives outbreak; Autoimmune disease; Chronic urticaria; head to toe body rash and hives outbreak; chronic fatigue sleeps 11 hours a day; Brain fog; This spontaneous case was reported by a consumer and describes the occurrence of AUTOIMMUNE DISORDER (Autoimmune disease) in a 42-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 033F21A, 014C21A and 028A1A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concomitant products included LAMOTRIGINE (LAMICTAL), BUPROPION HYDROCHLORIDE (WELLBUTRIN) and CLONAZEPAM (KLONOPIN) for an unknown indication.   On 25-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 23-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 26-Nov-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. In 2021, the patient experienced FEELING ABNORMAL (Brain fog) and FATIGUE (chronic fatigue sleeps 11 hours a day). On 05-Dec-2021, the patient experienced AUTOIMMUNE DISORDER (Autoimmune disease) (seriousness criterion medically significant), URTICARIA CHRONIC (Chronic urticaria), URTICARIA (head to toe body rash and hives outbreak) and RASH (head to toe body rash and hives outbreak). On 10-Dec-2021, the patient experienced SYNOVIAL CYST (Baker's cysts behind knee caps). The patient was treated with PREDNISONE on 07-Dec-2021 at a dose of UNK UNK, qd; LORATADINE (CLARITINE) at a dose of UNK, qd and DIPHENHYDRAMINE HYDROCHLORIDE (BENADRYL [DIPHENHYDRAMINE HYDROCHLORIDE]) at a dose of UNK, prn. At the time of the report, AUTOIMMUNE DISORDER (Autoimmune disease), URTICARIA CHRONIC (Chronic urticaria), SYNOVIAL CYST (Baker's cysts behind knee caps), URTICARIA (head to toe body rash and hives outbreak) and RASH (head to toe body rash and hives outbreak) outcome was unknown and FEELING ABNORMAL (Brain fog) and FATIGUE (chronic fatigue sleeps 11 hours a day) had not resolved.            No medical history was reported. The patient reported that she was seen numerous times but HCPs. Stated that she went to urgent care 07-Dec-2021 in which she was prescribed prednisone. Stated that she saw her primary care doctor on 09-Dec-2021 who did not know what this was and gave 15 more days of prednisone.   Stated on 10-Dec-2021 she went back to urgent care due to Baker's cysts behind knee caps and they did not prescribe anything and said to raise legs. Stated she saw an immunologist on 29-Dec-2021 and has a follow up 02-Feb-2022 for blood test results.  This is a spontaneous case concerning  a  42-year-old, female patient with no relevant medical history, who experienced the unexpected serious events of Autoimmune disorder and unexpected non-serious events of Urticaria chronic, Synovial cyst, Urticaria, Feeling abnormal and expected non-serious events of Rash and Fatigue. The events  Autoimmune disorder, Urticaria Chronic, Urticaria,  and Rash occurred approximately 9 days after the third dose of mRNA-1273 COVID 19 Vaccine. On the 14th day after the third dose of mRNA-1273 COVID 19 Vaccine, events synovial cyst occurred.  On an unknown date after the third dose of mRNA-1273 COVID 19 Vaccine, the events feeling abnormal, and fatigue happened. The rechallenge was unknown since no information about the first dose was disclosed. The events were reported as not resolved. The benefit-risk relationship of mRNA-1273 COVID 19 Vaccine, is not affected by this report.; Sender's Comments: This is a spontaneous case concerning  a  42-year-old, female patient with no relevant medical history, who experienced the unexpected serious events of Autoimmune disorder and unexpected non-serious events of Urticaria chronic, Synovial cyst, Urticaria, Feeling abnormal and expected non-serious events of Rash and Fatigue. The events  Autoimmune disorder, Urticaria Chronic, Urticaria,  and Rash occurred approximately 9 days after the third dose of mRNA-1273 COVID 19 Vaccine. On the 14th day after the third dose of mRNA-1273 COVID 19 Vaccine, events synovial cyst occurred.  On an unknown date after the third dose of mRNA-1273 COVID 19 Vaccine, the events feeling abnormal, and fatigue happened. The rechallenge was unknown since no information about the first dose was disclosed. The events were reported as not resolved. The benefit-risk relationship of mRNA-1273 COVID 19 Vaccine, is not affected by this report.