 I wondered if you might describe for a layperson, a non-scientist, this issue of the virus evolving. How would you explain that to somebody without, without a biology A level or similar? RNA viruses change a lot. HIV viruses are RNA viruses. Influenza viruses are RNA viruses. And they mutate. They mutate randomly. There's no thinking behind it. It just happens. And then those mutations which give the virus an advantage, it can more easily go from me to you. It can transmit easier. It can pass to other people. Those viruses will become the dominant strains in a community. We've seen that in the UK, South Africa as well, where a new mutation happened. It gave the virus an advantage. It was easy, more easily to transmit from one person to another, and it became the dominant strain. What is more worrying is that the fact that we now have people that have been infected and we're now starting to vaccinate people. Therefore, the virus that mutates in a way that escapes those vaccines or infections will give also those viruses an advantage, and they will become the dominant strains. The best way of preventing that is to reduce the amount of virus in the world, reduce the chances of mutations happening, and reduce the chance of that variant having an advantage and becoming dominant. And the best way of doing that is to reduce transmission, make the vaccines available globally, and prevent those variants happening. It's much easier to prevent than it is to respond to new variants coming into the population of viruses in the world.