of the 71,318 positive cases that were eligible for follow-up, 57,339 (80.4%) were reached and asked to provide details of their recent contacts
o blith y 71,318 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 57,339 (80.4%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar