Ysgrifennais atoch ar 16 Ebrill i amlinellu’r camau sy’n cael eu cymryd yng Nghymru mewn ymateb i’r achos presennol o’r frech goch yn ardal Abertawe. Hoffwn roi’r diweddaraf i chi ar y sefyllfa ddiweddaraf.
I wrote to you on 16 April to provide an outline of the actions being taken in Wales in response to the current outbreak of measles centred in the Swansea area.  I would like to provide a further update on the latest position.