Rydym wedi bod yn monitro feirysau fel y Norofeirws a Hepatitis mewn carthffosiaeth ddynol ers degawd, fel rhan o raglen i fesur lefelau’r feirysau hyn yn y gymuned.  Ychwanegon ni’r COVID-19 at y rhestr fonitro ym mis Mawrth eleni.
We have been monitoring viruses like Norovirus and Hepatitis in human sewage for the last decade, as part of a programme to evaluate levels of these viruses in the community. We added COVID-19 to the surveillance list in March this year.