Datganiad ysgrifenedig: Cyngor diweddaraf y Cyd-bwyllgor ar Imiwneiddio a Brechu (JCVI) ar gynhyrchion brechlyn ar gyfer ymgyrch brechiadau atgyfnerthu Covid-19 yr hydref
Written statement: JCVI updated advice on vaccine products for the autumn COVID-19 booster vaccination campaign