Er bod y brechlyn yn lleihau’r risg o salwch COVID difrifol, rydym yn dal i ddysgu am effaith y brechlyn ar drosglwyddiad y feirws, a gallai rhywun ei basio i eraill o hyd, hyd yn oed ar ôl cael y brechlyn.
Although vaccination greatly reduces the risk of severe COVID, we are still learning about how the vaccine affects transmission of the virus and someone could still pass it on even after being vaccinated.