of the 6,661 positive cases that were eligible for follow-up, 5,575 (84%) were reached and asked to provide details of their recent contacts
o blith y 6,661 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 5,575 (84%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar