We'll almost certainly need an annual covid vaccination for the same reasons we get annual flu vaccinations - with our current medical technology we can neither rid the planet of the virus nor obtain permanent immunity.

I didn't get flu shots in the past mostly because the shot hurts more than the flu, but COVID is another animal and pretty scary. Maybe they could be combined into a single poke.

In fact we have no idea how long this vaccine or any other [of the experimental covid-19 vaccines] will last for. They've got projections out to at least a year, but uncertainty becomes too great after that. It may last quite a long time, we don't really know.

for the same reasons we get annual flu vaccinations

No. We get annual flu vaccinations because flu viruses mutate significantly and quickly, so we're always getting vaccinated against new threats. Not against threats that we've forgot how to defend against.

[edited to clarify that the uncertainty is around the experimental vaccines; for old standards, we do have a very good idea]

You're right - I should have said "periodic vaccination", not annual.

Also yeah, there's a subtle difference between why we'd need periodic covid vaccinations vs flu vaccinations. But in the end the result is the same, we'll probably need to be re-vaccinated against covid over time.

Covid isn't going away because it has a non-human animal reservoir, so it's all about a strategy to prevent it's re-emergence into the sapiens reservoir. It's possible that periodic vaccinations of the population as a whole would be overkill and we could reactively immunize smaller populations as re-infection occurs.