I am in airports constantly, have traveled to 35 countries, every state, and average 30 states per year, and at least 4 3rd world countries per year. I have gotten the flu twice in my adult life, one of those times was the one and only year I got a flu shot.
And lab tests confirmed that it was actually the flu you had and also confirmed that the strain you had was the same as the strain you were vaccinated for?