Blood clots; vomiting; lost feeling in legs; instant horrible headache; This spontaneous case was reported by a consumer and describes the occurrence of THROMBOSIS (Blood clots), VOMITING (vomiting) and HYPOAESTHESIA (lost feeling in legs) in a male patient of an unknown age who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.    On an unknown date, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 01-Dec-2021, the patient experienced HEADACHE (instant horrible headache). On 06-Dec-2021, the patient experienced VOMITING (vomiting) (seriousness criterion hospitalization) and HYPOAESTHESIA (lost feeling in legs) (seriousness criterion hospitalization). On an unknown date, the patient experienced THROMBOSIS (Blood clots) (seriousness criteria hospitalization and medically significant). The patient was treated with Surgery (Brain Surgery) for Thrombosis. At the time of the report, THROMBOSIS (Blood clots), VOMITING (vomiting), HYPOAESTHESIA (lost feeling in legs) and HEADACHE (instant horrible headache) outcome was unknown.            Concomitant information was not provided. Treatment medication was not provided.  In Dec2021,patient had a blot clot on his brain and had surgery to clip it. He is in hospital after brain surgery and that will be a long road to recovery. Patient was  very healthy (vegan/sober).  Company comment: This Spontaneous case concerns a male patient of unknown age with no relevant medical history, who experienced the unexpected, serious (Hospitalization/ Medically significant) events of Vomiting, hypoaesthesia and AESI thrombosis. The patient experienced headache 1 day after receiving the third dose number of mRNA-1273 vaccine, as he did not improve and 5 days after developed vomiting and hypoaesthesia, he was transferred to hospital where he was diagnosed with brain thrombosis and had surgery to clip it. It was reported that the patient can not speak, however, it is not clear if it was referred to his current post operative status or a sequel. The rechallenge is not applicable, as the outcome of the event is unknown. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.   This case was linked to MOD-2021-406068 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 09-Dec-2021: Follow up received patient demographics and new events were added.; Sender's Comments: This Spontaneous case concerns a male patient of unknown age with no relevant medical history, who experienced the unexpected, serious (Hospitalization/ Medically significant) events of Vomiting, hypoaesthesia and AESI thrombosis. The patient experienced headache 1 day after receiving the third dose number of mRNA-1273 vaccine, as he did not improve and 5 days after developed vomiting and hypoaesthesia, he was transferred to hospital where he was diagnosed with brain thrombosis and had surgery to clip it. It was reported that the patient can not speak, however, it is not clear if it was referred to his current post operative status or a sequel. The rechallenge is not applicable, as the outcome of the event is unknown. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.