Every additional layer of protection that we get helps, and so I would highly recommend, especially somebody who's elderly who has yet gotten vaccinated to do so, because it really can go a long way towards giving you the durable and robust immunity that you want, this is definitely the time.

Stephen Kissler

It's really looking at that older age group and how much prior immunity they have, either from previous infection or vaccination, that I think has been the best indicator so far of how severe a given number of cases is going to end up being in terms of hospitalizations and deaths.

Stephen Kissler

I do still think it's a potential cause for concern that we may still see a higher case fatality rate and higher hospitalizations for Covid in United States than the UK because of the differences in underlying immunity.

Stephen Kissler