CCDD Director Prof. Lipsitch is featured in an interview to FiveThirtyEight sharing his views about flu, vaccination and best timing for it.
According the Dr. Lipsitch there are several studies showing that the effectiveness of the flu vaccine wanes towards the end of the season. The bottom line- it is better to get the vaccine later in the season as you have better chances of being protected from flu.
Challenges of vaccine effectiveness and waning studiesBest time for a flu shot? Before Halloween.