Special Investigation for Booster Dose of Comirnaty in Children Ages 6 Months Though 4 Years

COMIRNATY Intramuscular Injection for 6 Months to 4 Years Old (Monovalent: Omicron XBB.1.5) Special Investigation for Booster Immunization in Children Aged 6 Months to 4 Years

The purpose of this post-marketing study is to assess the safety of Comirnaty monovalent XBB.1.5. for booster vaccination children ages 6 months though 4 years under actual use medical practice.

Inclusion Criteria:

• Children aged 6 months to 4 years at the time of the booster vaccination (4th dose) who (or whose representative) gave written consent to take part in the study.

Exclusion Criteria:

-There are no exclusion criteria for this study.