Flu season is hardly over. But as people continue to queue up at doctors’ offices and pharmacies to get the vaccine, there is one thing the older set should consider: for senior citizens—the group for which the flu poses the biggest threat—shots are only 9 percent effective. This year, people older than 65 have been hospitalized for the flu at the highest rate in a decade, and this new discovery by the Centers for Disease Control and Prevention could be why.
