My paternal grandparents had no indoor plumbing. When I visited them as a child I was put in charge of bringing in water for coffee and breakfast oatmeal. I would run to the well and pump hard — with no result.
Then I’d remember the priming glass of water kept inside. Pouring it in the pump first always led to bountiful water.
The dramatic aspect of priming happens with many vaccines, which is one reason many are given as a series. Examples are DPT and polio. Priming also can occur with the flu vaccine, even though each year’s vaccine is different.
The reason I bring this up is because in the past few years many people — who previously received annual flu shots — have chosen not to.
What the media fail to report is that it is precisely that older population who have received flu shots over many years, who have the best chance of getting better “bang for the buck” via priming from all their previous vaccines.
And the strategy the CDC (Centers for Disease Control and Prevention) is now considering is to give two identical flu vaccines in the same season, with the first one being the priming dose for the second.