of the 673 positive cases that were eligible for follow-up, 570 (85%) were reached and asked to provide details of their recent contacts
o blith y 673 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 570 (85%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar