A Study to Investigate Cardiac Troponin Levels After mRNA-1273.712 Vaccine in Participants 12 Through 30 Years of Age

Exclusion Criteria

• •1. History of anaphylaxis or severe hypersensitivity reaction requiring medical intervention after receipt of any mRNA vaccine or therapeutic or any components of an mRNA vaccine or therapeutic.
• •2. Has known history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection within 3 months prior to enrollment.
• •3. Has a documented history of myocarditis or pericarditis.
• •4. Is acutely ill or febrile (temperature ≥38.0 degrees Celsius \[°C\]/100.4 degrees Fahrenheit \[°F\]) less than 72 hours prior to or at the Screening Visit or Day 1.
• •5. Has known conditions that may cause elevated cTnI.
• •* Cardiac disease/conditions including rhythm disorders and congenital heart disease
• •* Diabetes
• •* Uncontrolled hypertension (defined as systolic blood pressure \>140 millimeter of mercury (mmHg) or diastolic blood pressure \>90 mmHg)
• •* Alcohol or substance abuse
• •* Kidney disease
• •* Severe obesity, defined as body mass index (BMI) ≥40 kilograms per square meter (kg/m\^2) (\>20 years) or severe obesity defined as BMI for sex and age ≥120% of the 95th percentile \[BMI ≥35 kg/m\^2\] (for 12 to 20 years)
• •6. Currently has symptomatic acute or unstable chronic disease requiring medical or surgical care, to include significant change in therapy or hospitalization for worsening disease, at the discretion of the Investigator.
• •7. Has a medical, psychiatric, or occupational condition that may pose additional risk as a result of participation, or that could interfere with safety assessments or interpretation of results according to the Investigator's judgment.
• •8. Reported history of congenital or acquired immunodeficiency (eg, human immunodeficiency virus \[HIV\]), immunosuppressive condition or immune-mediated disease, asplenia, or recurrent severe infections disease.
• •9. History of Guillain-Barré syndrome.
• •10. Receipt of the following:
• •* Coronavirus disease 2019 (COVID-19) vaccine within 3 months prior to the first injection or if planning to receive at any time during the study (except for study intervention).
• •* Any other licensed vaccine within 28 days before the study injection or planned receipt prior to end of study (EOS).
• •* Systemic immunosuppressants or immune-modifying drugs for \>14 days in total within 6 months prior to Screening (for corticosteroids ≥10 milligrams (mg)/day of prednisone equivalent) or is anticipating the need for immunosuppressive treatment at any time during participation in the study.
• •* Systemic immunoglobulins or blood products within 3 months prior to the Screening/Baseline Visit or plans for receipt during the study.