of the 225,251 positive cases that were eligible for follow-up, 223,404 (99.2%) were reached and asked to provide details of their recent contacts
o blith y 225,251 o achosion positif a oedd yn gymwys i'w holrhain, cyrhaeddwyd 223,404 (99.2%) a gofyn iddynt ddarparu manylion y bobl y maent wedi dod i gysylltiad â nhw yn ddiweddar