of the 4,600 positive cases that were eligible for follow-up, 4,439 (96.5%) were reached and asked to provide details of their recent contacts
o blith y 4,600 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 4,439 (96.5%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar