That’s not correct. The CDC looks at strains that emerged generally in Asia early in te year, and makes the vaccine to cover the 3 most likely NEW strains.
His answer was to my specific inquiry about protection from the bird flu.
He did say that the shot mostly protects against the three strains that were likely to breakout. He also said that some of those had been around for years and some were from breakouts last year.
The CDC site says:
What is the flu shot? The flu shot is an inactivated vaccine (containing killed virus) that is given with a needle, usually in the arm. It contains three seasonal influenza viruses that are grown in eggs. The seasonal flu vaccine protects against three influenza viruses that research indicates will be most common during the upcoming season.
http://www.cdc.gov/FLU/about/qa/flushot.htm
Neither the CDC site nor the doctor indicated there was any currency in creating the vaccine, only likelihood of occurrence and history of breakouts.