And 2 articles from a quick Google search coincidentally show the same ~60% skip flu shots for both USA and UK:
https://abcnews.go.com/Health/ColdandFluNews/story?id=641897...
https://www.bbc.com/news/uk-scotland-42634781
If I didn't see the above, my intuition would have made me guess that 90%+ of medical professionals get flu shots. It turns out I was way off.
However, the reasons don't appear to be safety like this thread's article. One doctor said he doesn't get flu shots because the CDC makes a guess for what goes into the next season's flu shot and they're only ~50% correct. Since he got sick from the flu shot (even with the weakened virus) many years ago, he now avoids them. He still believes in the science of flu shot and not anti-vaxx but he personally chooses to not take it.
EDIT: Apologize for posting bad statistic. Is the UK NHS statistic accurate? If so, why do most UK health workers avoid it?