Today in the pandemic in October 2021 we have a situation where the high-income countries have now received enough doses of vaccines so that the whole population including adults and older children have been offered vaccines against COVID-19. And we're now even in a situation where there's consideration of programs for booster doses to improve protection further. And this is an immensely privileged position to be in just 10 months since the first vaccine doses were licensed. And the difficulty that we all face today is the inequity that there is globally. In many parts of the world in low-income countries there are no doses of vaccine available at this moment. So the real challenge is how do we deal with a situation where further doses used in high income countries for younger individuals as boosters will have perhaps a marginal gain over the huge protection we already have in our populations, whilst other populations of the world have had not received even their first dose. It's absolutely critical that those who are older adults, those with health conditions, and healthcare workers are prioritized globally to make sure that human populations everywhere are protected.