And if a few years down the road 100,000 people get Alzheimer's, or heart disease (just to mention two conditions known to be connected to inflammation)? It's remote in time, nobody has done long-term studies, so no one is interested in those people.
If it was certain there was no risk to immunizations, that would be a whole 'nother story. But it's not. When the risk of complications is high - whether it's human polio or canine parvo - that's a whole 'nother story too. But with the seasonal flu, it's not.

