# 6288
NIAID, part of the NIH, has just released a short (3 minute) video that nicely illustrates how flu viruses change antigenically over time, and eventually mutate so that the current flu vaccine no long is effective.
As the seasonal H3N2 virus that has been covered in the flu vaccine over the past 3 years has begun to accumulate changes like the ones discussed in this video, in the fall a new H3N2 strain will be incorporated in the flu shot.
There are currently 18 videos on the NIAID Youtube site, and links to others on other channels.
Well worth taking a look.
