What's Up Doc?: What's the deal with flu vaccines

  • Published
  • By Capt. (Dr.) Stephen Storey
  • 47th Medical Group
LAUGHLIN AFB, Texas --  Why do I get the flu vaccine every year if all other shots were only once, as a kid?

The flu vaccine is a very high profile vaccine because we must get it again each year. 
By some special mechanisms in its reproduction cycle, the influenza virus mutates and changes very fast, so that each year different strains are present. Therefore, the flu vaccine produced for a given year has a mix of the most common strains across America, a "Top Ten Hits" list for the flu virus, teaching our immune systems the newest virus fad. 
So, while you get protection for about a year, the virus will inevitably come back a little different later. The other infections that have a vaccine don't have quite this rapid of change and mutation. 
We now have the nasal form of Influenza vaccine which is squirted into the nostrils. This nasal form can be given starting at 5-years-old up until 50-years-old for normal healthy people who do not have any chronic diseases or poor immune systems (cancer therapy, chronic steroid use, advanced lung disease) or live with someone in that condition.
Individuals less than 5-years-old and more than 50-years-old, or those with chronic illnesses as above, will get the injection form of the flu shot. It may not totally prevent a case of flu, and it won't stop the common cold, but it can decrease the severity of illness should you get the flu.