Abstract
This study will evaluate the safety and immunogenicity of the mRNA-1273.214 vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concerns (VOCs) in participants aged 6 months to <6 years, when administered as a primary series in sars-cov-2 vaccine-naïve participants (part 1) and a single booster dose given to participants who previously received 2 doses of the mrna-1273 vaccine as a primary series (part 2).>
