Stroke; Gotten very sick from vaccine; Tachycardia; Blood pressure issues; Dizziniess; Heart rate issues; This spontaneous case was reported by an other health care professional and describes the occurrence of CEREBROVASCULAR ACCIDENT (Stroke) in a 40-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. #027L20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included COVID-19 (hospitalized for 7 days; treated with Remdesivir; long recovery) from 11-Sep-2020 to October 2020. Concurrent medical conditions included Blood pressure (ongoing issues) and Heart rate (ongoing issues).    On 05-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 03-Mar-2021, the patient experienced CEREBROVASCULAR ACCIDENT (Stroke) (seriousness criterion hospitalization). On an unknown date, the patient experienced ILLNESS (Gotten very sick from vaccine), TACHYCARDIA (Tachycardia), BLOOD PRESSURE FLUCTUATION (Blood pressure issues), DIZZINESS (Dizziniess) and HEART RATE IRREGULAR (Heart rate issues). At the time of the report, CEREBROVASCULAR ACCIDENT (Stroke), ILLNESS (Gotten very sick from vaccine), TACHYCARDIA (Tachycardia), BLOOD PRESSURE FLUCTUATION (Blood pressure issues), DIZZINESS (Dizziniess) and HEART RATE IRREGULAR (Heart rate issues) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 25-Mar-2021, SARS-CoV-2 antibody test: 9.64 after one round of the vaccine. On an unknown date, SARS-CoV-2 antibody test: 220 natural antibodies after 2 months.     mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) was withdrawn on an unknown date.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Patient reports that he had worked for an urgent care performing testing and contracted COVID-19 back in 11SEP2020. Patient was hospitalized for 7 days, was administered Remdesivir, and had a long recovery. Patient reports having issues regulating his blood pressure and heart rate so bad that he had almost died during that time. The recovery took up until 1st week of October and did not feel well until then. Patient reports it was advised to defer first dose of vaccination for COVID-19 for 3 months.   Patient self-medicated with OTC Tylenol and Advil which did not help. Patient reports that he was hospitalized a second time around last month (03MAR2021 approximately) for experiencing a stroke. Symptoms felt like he was experiencing a mini-COVID-19 episode and was having a relapse of COVID-19. ER professional advised patient to never take the second dose of the vaccine. Patient reports taking an antibody test (after a single dose of the vaccine) for both natural and for the spike protein on 25MAR2021. Patient reports that he had gotten a 9.64 reading from just one round of the vaccine in comparison to the doctors he had worked who had received both doses of the vaccine, never gotten sick with COVID-19, and produced a 9.0 reading. Patient reports his natural antibodies after 2 months was at 220. Patient wishes to report this information to highlight that his natural antibodies were so high from the previous COVID-19 infection that when he had gotten the first round of the vaccine, he believes that his body rejected the vaccine so strongly that he presented with severe side effects from the vaccine. Patient would like to submit his information to show that he is proof that if someone previously had COVID-19, they should only need a single dose of the vaccine. In addition, patient expressed that if a patient's natural antibody is high, then a reduced dose should be provided or the vaccine should be deferred until natural antibodies reduce   Most recent FOLLOW-UP information incorporated above includes: On 02-Apr-2021: Event details reported; Sender's Comments: Very limited information regarding the events has been provided at this time.  Further information has been requested.