there were 39,881 positive cases eligible for follow-up, of which 31,308 (78.5%) were reached and asked to provide details of their close contacts
o blith y 39,881 o achosion positif a oedd yn gymwys i gael camau dilynol, cafwyd gafael ar 31,308 (78.5%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar