Do we need boosters? At the moment, in October 2021, there is relatively little evidence about how boosters should be deployed, if and indeed for many people whether they're needed. After vaccination we develop an immune response that provides protection as we now know with the COVID-19 vaccines. And over time the immune response will start to fall, but that doesn't mean that protection disappears. Our immune system still remembers that we've had those two doses of the vaccine. And that will continue to be present, that memory will be present if we meet the virus again in the future. And for most people, that is likely to be sufficient to protect us from getting severe disease. There may be some people, particularly those whose immune systems are compromised, and maybe the very elderly, who will benefit from booster doses, at least in the short term. But in a pandemic we're learning all the time, and so it's critical we continue to watch the data to make sure that we are maximizing the use of vaccines to protect people in our populations. But at this moment we should be optimistic that for most people they have very good protection after two doses of the vaccines, and that experts all around the world are monitoring the situation closely so we can be offered boosters if and when they're needed. But in the short term protection still looks excellent.