VLA1553-403 Pregnancy Surveillance Study

Inclusion Criteria: VLA1553 vaccinated population: * Women who have received the single dose of the VLA1553 vaccine during pregnancy or within the 30 days prior to the first day of the last menstrual period. * Pregnant at the time of enrolment in the study. * The participant understands and agrees to comply with the study procedures. Control group: * Pregnant at the time of enrolment in the study. * Women who have received vaccine(s) approved for use during pregnancy by the MoH and who meet the matching criteria described in the protocol. * The participant understands and agrees to comply with the study procedures. * Women who have not received the VLA1553 vaccine during pregnancy or within the 30 days prior to the first day of the last menstrual period. Exclusion Criteria: * Women who do not provide informed consent. * Women who are not part of the target population of the pilot vaccination strategy at the time of vaccination.