Warning: There are going to be spoilers galore here.
To sum up: A new virus spreads among humanity, kills a bunch of us, then we cure it. The end.
Seriously, that's your whole film.
Ok, it's actually about the different families affected by the virus, and how they cope with the death of loved ones, and their communities breaking down.
Still, it's a long, plodding movie with no real point.
I guess it's a message about humanity, and how fragile we are, but how strong we are as well.
Whatever.
If the premise sounds interesting, see it. I've said nothing here that ruins the film, except for the cure thing, but c'mon, did you expect them to kill everyone?
If it doesn't sound interesting, skip it.
If you want the interactive version get "Plague Inc" on the iPhone as it's a simulator for releasing and mutating viruses into the population. It's pretty cool.