Enormous efforts have been made to provide booster vaccines to all eligible adults in the run-up to Christmas – almost 1.6m people have received a booster.
Mae ymdrechion enfawr wedi’u gwneud i ddarparu brechlynnau atgyfnerthu i bob oedolyn cymwys yn y cyfnod cyn y Nadolig – mae bron i 1.6m o bobl wedi cael brechlyn atgyfnerthu.