of the 4,756 positive cases that were eligible for follow-up, 4,593 (96.6%) were reached and asked to provide details of their recent contacts
o blith y 4,756 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 4,593 (96.6%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar