of the 34,985 positive cases that were eligible for follow-up, 30,217 (86.4%) were reached and asked to provide details of their recent contacts
o blith y 34,985 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 30,217 (86.4%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar