in the situation where good communication and access will help the vast majority of people, and will end up being vaccinated. but to fully protect the community in a country like the uk, with the numbers you've described, do you believe it would be right now to push the vaccination to 16 and i7—year—olds? indeed, in the us, they now are vaccinating all children over 12. do you think that is an important part of collective protection? well, i think at this moment, the key question for teenagers and younger children is whether or not vaccination of those groups has any direct benefit for them. and there's probably are a subgroup of children who have just slightly increased risk of severe disease. and definitely i think they should be included in vaccine programmes. but broader vaccination in childhood doesn't have so much direct benefit for them. so the real question is, will it prevent transmission and protect adults? and in a country like the uk, where the vast majority of adults are vaccinated, it's not such an important issue