she could not even walk; Pain was so severe that when in legs; Hives all over body after booster; Severe pain after booster/Still has mild pain after medication; Positive for blood clot after vaccine, but they could not find a blood clot per MD; Heart Rate doubles when in pain after booster (148 BPM); Pain all over body after booster and when pain comes; Booster injection site was closer to under the arm/Booster vaccine Injected in artery per MD; Extremes Pain in the right arm injection site after booster; This spontaneous case was reported by a consumer and describes the occurrence of THROMBOSIS (Positive for blood clot after vaccine, but they could not find a blood clot per MD) in a 55-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 042J21A, 048B21A and 038A21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.   On 25-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 25-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 29-Jan-2022, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 29-Jan-2022, the patient experienced INCORRECT ROUTE OF PRODUCT ADMINISTRATION (Booster injection site was closer to under the arm/Booster vaccine Injected in artery per MD) and VACCINATION SITE PAIN (Extremes Pain in the right arm injection site after booster). On 08-Feb-2022,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced THROMBOSIS (Positive for blood clot after vaccine, but they could not find a blood clot per MD) (seriousness criterion medically significant), HEART RATE INCREASED (Heart Rate doubles when in pain after booster (148 BPM)), GAIT DISTURBANCE (she could not even walk), PAIN IN EXTREMITY (Pain was so severe that when in legs), URTICARIA (Hives all over body after booster), PAIN (Severe pain after booster/Still has mild pain after medication) and PAIN (Pain all over body after booster and when pain comes). The patient was treated with LORATADINE at an unspecified dose and frequency. At the time of the report, THROMBOSIS (Positive for blood clot after vaccine, but they could not find a blood clot per MD), HEART RATE INCREASED (Heart Rate doubles when in pain after booster (148 BPM)), INCORRECT ROUTE OF PRODUCT ADMINISTRATION (Booster injection site was closer to under the arm/Booster vaccine Injected in artery per MD), GAIT DISTURBANCE (she could not even walk), PAIN IN EXTREMITY (Pain was so severe that when in legs), URTICARIA (Hives all over body after booster), PAIN (Severe pain after booster/Still has mild pain after medication), VACCINATION SITE PAIN (Extremes Pain in the right arm injection site after booster) and PAIN (Pain all over body after booster and when pain comes) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 08-Feb-2022, Heart rate: 148 (High) 148 BPM.         Concomitant medication were not reported.  Patient had no adverse reactions after first and second doses of Moderna. Patient administered Steroid pack twice but still had mild pain, hives appear with heat.  Company comment:This is a spontaneous case concerning a 55-year-old, female patient with no reported medical history and with vaccine history of receiving first and second dose of mRNA-1273 vaccine with no reported adverse events, who experienced the unexpected serious (medically significant) AESI event of thrombosis and unexpected non-serious events of severe pain, hives all over the body, general body pain, heart rate increased, gait disturbance and leg pain, the expected non-serious event of vaccination site pain. Incorrect route of product administration was also reported. The event vaccination site pain and reported incorrect route of product administration occurred the same day after the third dose of mRNA-1273 vaccine administration while the events thrombosis, severe pain, hives all over the body, general body pain, heart rate increased, gait disturbance and leg pain occurred 10 days after the third dose of mRNA-1273 vaccine administration. Allegedly the events were described as, 10 days after the booster dose patient experienced severe pain and sought consult to hospital. The doctor told her that the vaccine injection was given in her artery. The injection site was closer to under the arm and patient experienced extreme pain in the vaccinated right arm. The doctor stated to the patient that she came out positive for blood clot, however they could not find a blood clot. Patient also started having hives all over her body, pain all over body and when in pain her heart rate doubles (148 BPM). Patient had finished steroid pack twice but still has mild pain and hives appear with heat. The skin feels hot first and then hives kick in, on & off on different body parts. Patient takes Loratadine. Pain is so severe in legs, she can not even walk. She does not wish to appear in public places and work, when adverse events kick in. The outcome of the events were unknown. The incorrect route of product administration remain confounder. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a spontaneous case concerning a 55-year-old, female patient with no reported medical history and with vaccine history of receiving first and second dose of mRNA-1273 vaccine with no reported adverse events, who experienced the unexpected serious (medically significant) AESI event of thrombosis and unexpected non-serious events of severe pain, hives all over the body, general body pain, heart rate increased, gait disturbance and leg pain, the expected non-serious event of vaccination site pain. Incorrect route of product administration was also reported. The event vaccination site pain and reported incorrect route of product administration occurred the same day after the third dose of mRNA-1273 vaccine administration while the events thrombosis, severe pain, hives all over the body, general body pain, heart rate increased, gait disturbance and leg pain occurred 10 days after the third dose of mRNA-1273 vaccine administration. Allegedly the events were described as, 10 days after the booster dose patient experienced severe pain and sought consult to hospital. The doctor told her that the vaccine injection was given in her artery. The injection site was closer to under the arm and patient experienced extreme pain in the vaccinated right arm. The doctor stated to the patient that she came out positive for blood clot, however they could not find a blood clot. Patient also started having hives all over her body, pain all over body and when in pain her heart rate doubles (148 BPM). Patient had finished steroid pack twice but still has mild pain and hives appear with heat. The skin feels hot first and then hives kick in, on & off on different body parts. Patient takes Loratadine. Pain is so severe in legs, she can not even walk. She does not wish to appear in public places and work, when adverse events kick in. The outcome of the events were unknown. The incorrect route of product administration remain confounder. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.