Apparently, there is a trend on cruise ships to put extra fat in the food which can have a laxative effect on a person. This is to make sure all of the ship's plumbing works properly and that there is little to no chance of the plumbing getting clogged or backed up.
You can get norovirus from an infected person, from contaminated food or water, or by touching contaminated surfaces. The virus causes your stomach or intestines or both to get inflamed (acute gastroenteritis). This leads you to have stomach pain, nausea, and diarrhea and to throw up.