Mae canlyniadau cynnar yn y dystiolaeth o effeithiolrwydd y brechlynnau yn addawol o ran eu heffaith ar atal salwch difrifol ac atal trosglwyddo. Ond, hyd nes inni gyrraedd camau pellach y rhaglen frechu, bydd cyfran helaeth o’r boblogaeth yn dal mewn perygl o ddal yr haint.
Early results about the effectiveness of the vaccines are promising in terms of their effect in both preventing severe disease and transmission. But, until the vaccination programme is more advanced, a large proportion of the population will remain vulnerable to infection.