The flu shot is a sort of "greatest hits" of the previous flu season, weakened and mixed in together... but there are always novel flus new to the season that can infect anyone... immunised or not. So even when there is a vaccine, anyone can catch a new version of the virus. When we think of this ability to mutate, we can recall that the common cold is a coronavirus, we can and do catch new colds. They mutate and return, it's what they do. And so, we do need pre-vaccine strategies that maximise total population health, maximise care of children and keep society functioning maximally - to at least, "first do no harm." Moreover, we need a fitter society that has time to exercise and eat right, time to have fun and de-stress. Perhaps this is a terrible way to learn that we need to be kinder to our bodies and brains. Perhaps it's time to get serious about implementing bio-medically appropriate social policies.