I thought that type Bs got the flu more easily than the others!
In ER4YT, p. 284, Dr. D says: "Influenza, ..., also strikes Type O and Type B in preference to Type A and Type AB."
So I think the recommendations for shots are all off.
DS, a B, insisted on getting a flu shot this year, and I didn't mind taking him and paying for it. But I didn't get one myself.
I'm now 64 and I've had the flu in the past, which was really bad. I got the flu shot a couple of years ago, two years, as it was recommended for 'the elderly'. I can't remember if I got one last year, possibly not, and at the time considered myself 'lucky'.