Flu shot effective less than half the time

The flu is widespread right now in Florida. Because of that, chances are pretty good either you or someone you know has or had it, despite having gotten the flu shot.

Numbers from the Centers for Disease Control and Prevention show the shot is effective less than half the time. 

Overall, getting a flu shot cut one’s risk of contracting flu and needing to see a doctor by 48 percent this season, when the effectiveness of the various components of the vaccine were assessed together, according to the CDC. 

Far and away the most common cause of influenza so far this year is the influenza A virus family known as H3N2. Seasons when H3N2 viruses dominate are typically harsh because the virus is especially hard on older adults. Older adults also get less benefit from flu vaccines than healthy younger people.

As well, the H3N2 component of the flu vaccine has not worked as well as other components in recent years. Flu vaccines are combination vaccines, protecting against three and sometimes four different flu strains.