Rise of the Planet of the Apes was a good movie that worked as a nice prequel to a classic film franchise while also standing alone as a sci-fi monkey drama.
Dawn of the Planet of the Apes was a great movie that kicked everything up a notch and went into far greater emotional depths while being a true blockbuster experience as well. However, it worked so well partially because of how standalone it was from its predecessor. The human cast does not return, and our cast from the original have character arcs independent of those they had in the original movie.
This opening scene, then, acts as a bridge between those movies, but also as its own standalone art piece of a pandemic growing and human society collapsing. The peaceful globe-spinning graphics mixed with the increased panic of the archival footage makes for an unnerving intro that firmly sets the tone for the rest of the film.
Sequels do these sorts of “recap the previous movie” intros all the time, but rarely do they succeed on an artistic level all their own. Dawn of the Planet of the Apes is special.