How could you possibly know this if no one is tested before they are given the vaccine? Isn't it just an assumption based incorrectly on vaccine-acquired immunity which indeed is much shorter lived. I believe I read somewhere on the CDC website that the maximum length of immunity from the vaccine is 126 days.
I ask again, why would you not first find out if someone retains their immunity before shooting them up with a quadrivalent vaccine cocktail?
Are you of the belief that vaccine-acquired immunity is superior to naturally acquired immunity?
I know about the decay of immunity over time, because this is a very heavily researched subject. Most diseases do not cause permanent immunity.
I ask again, why would you not first find out if someone retains their immunity before shooting them up with a quadrivalent vaccine cocktail?
Why would I subject someone to a painful and invasive blood test, especially when the justification is so thin? I *know* they have some influenza antibodies, that isn't the issue. Whether they have antibodies that will protect them from the circulating strains is something different, and not that straightforward to test. I think that developing such a test for every single circulating strain of influenza would be expensive, and not quite as precise as people might believe.
Personally, I do not inject anyone with anything. I am a PhD, not an MD, and have no direct involvement in patient care. I am, however, a medical researcher, and vaccines (influenza, especially) are one of my subspecialties. Influenza vaccine technology is decades old, with the exception of the newer cell-based vaccines. It has a long and proven track record. I'd rather get a little injection that have someone pierce my arm with a huge needle to draw out copious quantities of blood for a questionable test of whether I'm immune to the circulating strains.