When I first started off in medicine, the flu vaccine was offered in September and October for the impending flu season of that year. Now the flu season is all year long. When was the last time you called the pharmacy? Any time of year, you will hear their advertising of the flu shot, no out of pocket expense, come in anytime….
Now the important question, does the flu shot work? Does the flu shot cause the flu?

For the website:
In short, there was an outbreak on a naval carrier where the immunization rate was 99%. The flu strain of their illness was conclusively linked to the flu immunization given to these sailors.
How effective is the shot? For the elderly (over 65) it is minimally effective. For younger folks, it may be 43% effective the first year, but the second year of vaccination, an immunized person may be 15% more likely to get the flu! What about year 3, year 4…? No research on this.

Navy Proves Flu Shot Causes Flu