On the question of whether we need to update the vaccines: Sara Gilbert spoke to this in some detail in her TWiV interview [813]. They have been testing version

On the question of whether we need to update the vaccines: Sara Gilbert spoke to this in some detail in her TWiV interview [813]. They have been testing versions specific to other variants, but haven't found a real need. Delta is not very different antigenically than the ancestral type - beta and gamma are more so, but delta is winning because it's more transmissible. The story becomes quite complex when you get into details - the T and B memory cells broaden the response, so are unlikely to need much updating. [813]: https://www.youtube.com/watch?v=A_5o6qZyyQk&t=1145s https://www.youtube.com/watch?v=A_5o6qZyyQk&t=1145s