Norwalk Virus - Not Just for Cruise Ships?

So Ben and Joel got home late yesterday afternoon from their trip to Charleston, where they had a good time despite getting little sleep (apparently sleeping with 540 boys in the crew quarters of an aircraft carrier does not make for a restful night). Joel did take a few pictures, which I will post later when I have a chance. The footnote to the trip is that at 4:30 this morning Ben woke up with vomiting and diarrhea. Coincidentally (or not), I learned later this morning that Ben's friend Jared, also on the trip this weekend, woke up at exactly 4:30 this morning with the same symptoms. I'm now trying to keep Ben hydrated between frequent trips to the bathroom, and wondering how many other boys might have gotten sick as well??