of the 173,640 positive cases that were eligible for follow-up, 173,022 (99.6%) were reached and asked to provide details of their recent contacts
o blith y 173,640 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 173,022 (99.6%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar