On the 100th anniversary of the terrible flu pandemic of 1918 that is believed to have killed between 50 and 100 million people worldwide, it's natural to stop and wonder: What exactly is a pandemic? Is it just a bad year of the regular, seasonal flu?
There are some significant differences beween the two, the U.S. Centers for Disease Control and Protection says. The CDC just put out a graphic with a quick, side-by-side comparison of seasonal flu and flu pandemics.
There have been four pandemics in the past 100 years, with the most recent one in 2009.
The CDC graphic makes for some interesting reading. You can find it here.
Of course, the most important practical information to glean from all this is that almost everyone ages 6 months or older should get their flu shots!