No vaccine offers 100% protection. However, the flu vaccines have been shown to give good protection. Those who have the vaccine and are still unlucky enough to catch flu should have a milder dose.
Rydym yn croesawu gohebiaeth a galwadau ffôn yn y Gymraeg neu'r Saesneg. Atebir gohebiaeth Gymraeg yn y Gymraeg, ac ni fydd hyn yn arwain at oedi. Mae’r dudalen hon ar gael yn Gymraeg drwy bwyso’r botwm ar y dde ar frig y dudalen.
We welcome correspondence and telephone calls in Welsh or English. Welsh language correspondence will be replied to in Welsh, and this will not lead to a delay. This page is available in Welsh by clicking ‘Cymraeg’ at the top right of this page.