of the 695,643 positive cases that were eligible for follow-up, 644,303 (92.6%) were reached and asked to provide details of their recent contacts
o blith y 695,643 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 644,303 (92.6%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar