She passed out twice and daughter called paramedics; Became violently ill and had to go to ER; She also fell and hit her head; She also fell and hit her head; Shaking; Doctor conveyed after patient took the vaccines her immunity may have gone higher; Fever of 102F; Chills with shaking; Headache to the extreme; This case was received via an unknown source (no reference has been entered for a health authority or license partner) on 03-Jan-2022 and was forwarded to Moderna on 03-Jan-2022.    This spontaneous case was reported by a consumer and describes the occurrence of LOSS OF CONSCIOUSNESS (She passed out twice and daughter called paramedics) in a 75-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 045521A, 015M20A and 011L20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.   On 12-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 13-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 14-Dec-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 14-Dec-2021, the patient experienced LOSS OF CONSCIOUSNESS (She passed out twice and daughter called paramedics) (seriousness criterion medically significant), ILLNESS (Became violently ill and had to go to ER), FALL (She also fell and hit her head), HEAD INJURY (She also fell and hit her head), IMMUNE SYSTEM DISORDER (Doctor conveyed after patient took the vaccines her immunity may have gone higher), PYREXIA (Fever of 102F) and HEADACHE (Headache to the extreme). 14-Dec-2021, the patient experienced TREMOR (SHAKING) and CHILLS (Chills with shaking). At the time of the report, LOSS OF CONSCIOUSNESS (She passed out twice and daughter called paramedics), ILLNESS (Became violently ill and had to go to ER), FALL (She also fell and hit her head), HEAD INJURY (She also fell and hit her head), TREMOR (Shaking), IMMUNE SYSTEM DISORDER (Doctor conveyed after patient took the vaccines her immunity may have gone higher), PYREXIA (Fever of 102F), CHILLS (Chills with shaking) and HEADACHE (Headache to the extreme) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 30-Dec-2020, SARS-CoV-2 test: positive (Positive) Positive for COVID-19 in 30-DEC-2020 prior to receiving the Moderna vaccines. On 14-Dec-2021, Pyrexia: 102 (High) fever of 102F. On an unknown date, Laboratory test: not provided (Inconclusive) Not provided.         No concomitant medications were reported. No treatment medications were reported.  Patient called to report severe side effects from Moderna second dose and Moderna Booster shot. Patient received booster on 14-DEC-2021. Beginning 14-DEC-2021 she became violently ill and had to go to ER. She passed out twice and her daughter called paramedics. She also fell and hit her head when she passed out. She had fever of 102F, chills with shaking, and had a headache to the extreme. Patient felt her side effects were more severe. ER ran several tests, they told her they hadn't seen any side effects this severe. Doctor conveyed after patient took the vaccines her immunity may have gone higher. She felt he was trying to make her feel better.   This case was linked to MOD-2022-437413.; Sender's Comments: This is a regulatory case concerning a 75-year-old female patient with no medical history provided, who experienced the serious unexpected event of Loss of consciousness(seriousness criterion medically significant).This event occurred on the same day the patient received their third dose of mRNA-1273 (Moderna COVID-19 Vaccine)The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report. Events seriousness assessed as per Regulatory Authority reporting.