there were 11,663 positive cases eligible for follow-up, of which 9,940 (85.2%) were reached and asked to provide details of their close contacts*
o blith y 11,663 o achosion positif a oedd yn gymwys i gael camau dilynol, cafwyd gafael ar 9,940 (85.2%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar*