Many zombie series start with the overly used hunting trip or coma to explain why the protagonist has no idea whats happening. This usually so the writer can dump the reader with what happened, saving time. What other explanations could I use to explain the protagonists lack of knowledge?
How about a sailing trip? A small crew or even a single man sailing across a wide body of water, like the Pacific? That might provide sufficient time away from land, and sufficient isolation from communications, to provide what you need.
Those seem to be the biggest problems - overcoming the invasive presence of communication, and the speed of modern communication, along with allowing time for whatever's causing the apocalypse to spread to a pandemic.
An alternative might be a more rural setting, at a time in the past when communications were more difficult and mass media didn't yet exist. If mass communication is less available, and focused in one location - some small towns only had a single operator to connect them to the outside world - losing touch is far easier.
Brainstorming with a whiteboard or a pad of paper can really be beneficial in coming up with ideas, though. You might want to give that a try.