I took my 5-year-old to see the live-action version of "The Lion King" last weekend. While we were waiting for the film to begin, we were subjected to a commercial for Disney's cruise line, sold as a family-friendly excursion with your favorite Disney characters. My son, of course, was ready to go tomorrow. I didn't have the heart to tell him that, as my child, he's never getting on one of those things.

I know plenty of people love cruises. The convenience of seeing a variety of places without having to plan them individually; the all-inclusive meals; the variety of entertainment options; and for those with kids, the special activities provided for youngsters. I get it. But as an individual trained in microbiology and infectious diseases, what I see when contemplating such an excursion is the potential to be trapped with thousands of others in a confined space, suffering from gastrointestinal aliments like norovirus and E. coli, respiratory infections including influenza and chickenpox, or, as a recent Scientology cruise demonstrated, measles. And that just doesn't sound like a fun vacation to me.

Granted, I could become ill via any type of travel, or even via a staycation with my kindergartener. But cruise ships take those risks of background infection and amplify them.

This is hardly a secret: Just this week it was reported that inspectors from the Centers for Disease Control and Prevention gave the Carnival ship “Fantasy” one of the company’s worst ever sanitation inspection reports. (The Carnival Corp. & PLC made close to $19 billion in full revenues in 2018.)

Granted, I could become ill via any type of travel, or even via a staycation with my kindergartener. But cruise ships take those risks of background infection and amplify them due to the constant shared quarters of travelers onboard. The ships are notoriously difficult to clean when a case of norovirus is diagnosed. And norovirus is so infectious that it's almost impossible to avoid in close quarters — a mere 10 viral particles is enough to make someone sick. I've suffered through a travel-related norovirus illness alone in a hotel before and it was horrible. I can't even imagine how much worse it would have been if I was sharing that tiny room (and that nasty virus) with my family.

View this graphic on nbcnews.com

While norovirus is the key cruise ship pathogen, other stomach bugs can proliferate as well. Among the violations reported on Carnival’s “Fantasy,” for example, included “brown water discharged from two shower hoses in the medical center.” The medical center! The main pool gutters on the 855-foot ship were also not functioning correctly: “There was a visible film on the top of the water, and there was excessive visible debris floating on the water.”

And inspectors observed a general lack of attention to food safety throughout, including deficiencies “related to food equipment and facilities, protection of food and clean items, handling of waste and soiled items, food employee knowledge, and food employee managerial control.” Utensils for the buffets were stored in soiled water, or dirty ones were added in with clean utensils; water was leaking onto containers of vegetables; sneeze guards were missing or improperly used; breads with visible fly contamination were reused; and on and on.

Seriously, I’ll pass.

While this most recent inspection may be an outlier, the CDC investigates an average of 12 to 13 gastrointestinal disease outbreaks on cruise ships each year, monitored by the Vessel Sanitation Program (VSP). And while I can readily avoid local restaurants that have poor ratings from food inspections, once you're on the ship, you're basically stuck when it comes to dining options.

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And the purview of the VSP is gastrointestinal infections — not all infections. Respiratory infections very likely go under-reported for a variety of reasons, including lack of diagnostic capabilities on the ship, and a lack of knowledge by employees or passengers that such illnesses should be reported to health officials. Such infections could easily be transmitted on the ship, and because their incubation period may be days or weeks, could go undiagnosed until after you return home.

I realize that in the bigger picture, most cruise travelers will be just fine. The CDC notes: “From 2008 to 2014, 74 million passengers sailed on cruise ships in the Vessel Sanitation Program’s jurisdiction. Only 129,678 passengers met the program’s case definition for acute gastrointestinal illness and only a small proportion of those cases (1 in 10) were part of a norovirus outbreak.”

But personally, I’d rather not take the risk. (There’s also the small but very real chance you could get stranded, fall overboard or spend the trip without working plumbing.) For those of you who are cruise lovers and want to know how your ship rates, you can check the vessel’s inspection history before you book or travel to see if they have a history of brown water or fly-bagels. For those of you who abstain like myself, I'll still see you at the beach — I'll just drive or fly there instead.