of the 208,209 positive cases that were eligible for follow-up, 207,164 (99.5%) were reached and asked to provide details of their recent contacts
o blith y 208,209 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 207,164 (99.5%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar