Venous thromboembolism; This literature-non-study case was reported in a literature article and describes the occurrence of EMBOLISM VENOUS (Venous thromboembolism) in a  patient of an unknown age and gender who received mRNA-1273 (Spikevax) for COVID-19 prophylaxis.       No Medical History information was reported.    On an unknown date, the patient received second dose of mRNA-1273 (Spikevax) (unknown route) 1 dosage form. On an unknown date, the patient experienced EMBOLISM VENOUS (Venous thromboembolism) (seriousness criterion medically significant). At the time of the report, EMBOLISM VENOUS (Venous thromboembolism) outcome was unknown. Not Provided      For mRNA-1273 (Spikevax) (Unknown), the reporter did not provide any causality assessments.   Concomitant and treatment medications were not reported. This case refers to a patient of unknown age and gender who experienced the Venous thromboembolism after second dose of mRNA-1273 vaccine.   This study described simultaneous vaccination (SV) with primary series COVID-19 vaccines and assess 23 pre-specified health outcomes following SV among persons aged greater than or equal to 5 years in the Vaccine Safety Datalink (VSD). from December 11, 2020-May 21, 2022. Analyses assessed frequency of SV.   Rate ratios (RRs) were estimated by Poisson regression when the number of outcomes was greater than or equal to 5 across both doses, comparing outcome rates between COVID-19 vaccinees receiving SV and COVID-19 vaccinees receiving no SV in the 1-21 days following COVID-19 vaccine dose 1 and 1-42 days following dose 2 by SV type received.  The most frequent simultaneous vaccines were influenza, HPV, Tdap, and meningococcal. Outcomes following SV with COVID-19 vaccines were rare (total of 56 outcomes observed after dose 1 and dose 2). Overall rate of outcomes among COVID-19 vaccinees who received SV was not statistically significantly different than the rate among those who did not receive SV.  Authors concluded that overall, the combined pre-specified health outcomes observed among persons who received simultaneous vaccines with COVID-19 vaccine were also rare and not at a statistically significantly different rate compared with those who did not receive simultaneous vaccination with the COVID-19 vaccine. Statistically significant adjusted rate ratios were observed for some individual outcomes (appendicitis, convulsions/seizures, and Bell's palsy), but the number of cases was small, there was no adjustment for multiple testing, and the possible effect of residual unmeasured confounding in these analyses may have contributed to these findings.  This case was linked to US-MODERNATX, INC.-MOD-2023-731103 (Linked Report).; Reporter's Comments: Company comment: This literature non study case concerns a patient of unknown age and gender, with no medical history information reported, who experienced the unexpected serious (medically significant) AESI of venous thromboembolism. The events occurred after the second dose of mRNA-1273 (1-42 days after 2nd dose). No further information about the event was provided. The benefit-risk relationship of mRNA-1273 is not affected by this report.; Sender's Comments:  US-MODERNATX, INC.-MOD-2023-731103:Master case