Edrychodd y JCVI ar risgiau a manteision allweddol cynnig ail ddos i bobl ifanc 16-17 oed. Wrth wneud eu penderfyniad, ystyriwyd bod ail ddos yn cynnig amddiffyniad hirach rhag COVID-19, ac yn lleihau’r risg o haint a salwch difrifol, derbyniadau i’r ysbyty a derbyniadau i unedau gofal dwys ymhellach. Cafodd y manteision hyn eu cydbwyso â data sy’n dangos digwyddiadau niweidiol prin iawn ar ôl brechiadau mewn pobl ifanc.
The JCVI looked at the key benefits and risks of offering a second dose to 16-17 year olds and found that a second dose offered more durable protection against COVID-19 and further reduced the risk of infection and serious illness, hospitalisation and intensive care unit admission. These benefits were balanced against data showing the rare incidence of adverse events following vaccination in young people.