of the 16,956 positive cases that were eligible for follow-up, 15,700 (92.6%) were reached and asked to provide details of their recent contacts
o blith y 16,956 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 15,700 (92.6%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar