Gwnaeth y Prif Swyddog Milfeddygol gynnal nifer o ymarferion gyda'r plant gan gynnwys chwarae gyda "germau" anweledig, ysgwyd llaw a'r her "golchi welis".
The CVO carried out a number of exercises with the children including playing with "invisible" germ, shaking hands and a “dirty or clean” challenge.