Cruise lines also have different rules when it comes to their pool decks. Carnival and Royal Caribbean allow beverages in their pool as long as they're not in glasses. MSC Cruises does not allow any beverages in its pools, even in its adults-only pool areas.

In addition to hand-washing, every cruise line has increased its cleaning and sanitization efforts. Walk around any public area on a Carnival or Royal Caribbean ship - especially ones where people eat — and you see crew members with cleaning supplies waiting to swoop in when a passenger leaves in order to sanitize before someone else sits down.

When you board a Carnival or Royal Caribbean cruise ship, a lot of passengers head right for the onboard pizza place, It's not that the pizza is overly good (although some people really love it), it's just that free,

That's a good idea because it helps passengers make friends with people who may not agree with them on every issue. Sign up for the Come Cruise With Me newsletter to save money on your next (or your first) cruise.