I was hospitalized with double pneumonia in April 2021; Diagnosed with myelodysplasia/ Suffered with extremely low blood platelets; This spontaneous case was reported by a patient and describes the occurrence of PNEUMONIA (I was hospitalized with double pneumonia in April 2021) and MYELODYSPLASTIC SYNDROME (Diagnosed with myelodysplasia/ Suffered with extremely low blood platelets) in a  patient of an unknown age and gender who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.     No Medical History information was reported.   In February 2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 25-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. In April 2021, the patient experienced PNEUMONIA (I was hospitalized with double pneumonia in April 2021) (seriousness criteria hospitalization and medically significant). In October 2021, the patient experienced MYELODYSPLASTIC SYNDROME (Diagnosed with myelodysplasia/ Suffered with extremely low blood platelets) (seriousness criterion medically significant). At the time of the report, PNEUMONIA (I was hospitalized with double pneumonia in April 2021) and MYELODYSPLASTIC SYNDROME (Diagnosed with myelodysplasia/ Suffered with extremely low blood platelets) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Platelet count: Low.         Concomitant product use was not provided by the reporter.   Patient was suffering from extremely low blood platelets and received frequent transfusions as treatment. Patient was examined and treated by multiple physicians but none of the physician had been able to diagnose or prescribe a treatment for the mentioned symptoms.  Company comment-This spontaneous case concerns a patient of unspecified gender and age with no medical history reported, who experienced the unexpected serious (Medically significant/Hospitalization) event of Pneumonia, unexpected serious (Medically significant) event of Myelodysplastic syndrome after second dose of mRNA-1273 vaccination in covid -19 vaccination series. Pneumonia occurred unspecified days in April2021, Myelodysplastic syndrome approximately 7 months after vaccination. Patient has extremely low platelet count and receives frequent transfusions as advised by oncologist. No further information on risk factors, detailed clinical course, investigations, treatment of the events was available in the report. Outcome of the events was not known at the time of report. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.   This case was linked to MOD-2022-667987 (Patient Link).; Sender's Comments: This spontaneous case concerns a patient of unspecified gender and age with no medical history reported, who experienced the unexpected serious (Medically significant/Hospitalization) event of Pneumonia, unexpected serious (Medically significant) event of Myelodysplastic syndrome after second dose of mRNA-1273 vaccination in covid -19 vaccination series. Pneumonia occurred unspecified days in April2021, Myelodysplastic syndrome approximately 7 months after vaccination. Patient has extremely low platelet count and receives frequent transfusions as advised by oncologist. No further information on risk factors, detailed clinical course, investigations, treatment of the events was available in the report. Outcome of the events was not known at the time of report. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.