1st Gulf had some problems with one of the vaccines. Can't remember which one it was, but they had to stop administering it.The Gulf War vaccinations were a pretty limited set. FWIW, I didn't even know such a thing existed.
Flu vaccines are somewhat more limited. Anyone know what the percentages were for those? I personally never got one.
And it's the reason why the military hasn't made the covid vaccine mandatory (so far).
One of my ex-gfs of the time was one of the people working on that stuff. Used to call soldiers/sailors/airmen/marines "test dummy pin cushions" or something like that.