Are cruise ships really just floating petri dishes?

Are cruise ships really just floating petri dishes?

I grew up on the Costa del Sol watching cruise ships pass on the horizon and wondering what life looked like on the other side of that railing. At twenty-six, after the financial crisis took my business with it, I found my way to ships. Fifteen years later, having worked my way from entry level to senior officer on some of the world’s most demanding routes, I moved inland to Antequera and started… Source