Over 20 million Americans go on commercial cruises very year. It’s a massive industry and one that hasn’t held any appeal for me. Ever.
But there’s one main thing that makes me never want to take a cruise, an occurrence so common that it’s called the cruise ship disease. I was working in a free clinic when a ship pulled up due to an outbreak. Our port is pretty small and normally only small cruise ships stop in, but a massive cruise ship in distress requiring medical assistance for its passengers docked. It was a strange sight. Our city, known for its small dimensions, had a ship with more stories than some of our famous landmarks. Our clinic saw a bunch of the cruise ship passengers as they didn’t have health insurance. I really felt for them. They were very sick, dehydrated, far from home and deeply concerned about the medical costs. It’s scary to be without health insurance but to get sick away from home without it? Nerve wracking!
Courtesy: barfblog.com
A spokesperson for the cruise line (eventually investigated by the feds) at the time blamed the passengers claiming, “In addition to our cleaning procedures, we rely on passengers’ compliance and good hygiene habits and the two of these must work in tandem to eradicate an outbreak.”
So what causes this? It can't just be a few people skipping washing their hands right? Why is it so common on cruise ships?
The virus behind cruise ship disease is norovirus. Viruses are pieces of information that insert themselves and hijack your cell's machinery to replicate. They don't always cause disease but when they do it can be deadly. Norovirus is transmitted through water, food, or contact with contaminated body fluids like vomit. Sounds delightful! The virus replicates in the small intestine (the long wiggly part of your guts). The symptoms can come on really fast, anywhere from 12 hours to 2 days. A 12 hour reaction is insanely quick. Once infected you can spend from to 1 to 3 days with serious symptoms like diarrhea and vomiting. You're especially contagious when your body is doing its best to get rid of it from both ends. Dehydration can occur quickly.
Often with a lot of viruses once you're exposed you raise a defense and your body keeps a memory of what you fought off. Norovirus immunity doesn't last very long and that's likely the reason why you can be infected more than once. So if you're really into cruises you're susceptible each time. Which stinks because it only takes a tiny tiny amount of the viral particles to infect you.
So why are cruise ships such fantastic breeding grounds for norovirus? Well for one, you have a contained space, then thousands of people sharing buffets, plus recycled gray water used for cleaning linens and decks, chairs and outdoor surfaces. Cruise ships catering to families have the added bonus of small vectors of disease known as children. Kids are fun, but they aren't paragons of cleanliness. Cruise ships also have a very short time between passenger rotations so they amount of time available for deep cleaning is limited.
Norovirus is pretty hearty and can live up to a week on stainless steel surfaces (the material most commercial kitchen counters are made of). The main method of transmission is the fecal-oral route. Ew, but true! So it wouldn't take much for an infected chef to start a chain reaction of infection, a dirty handed passenger sliming the seafood buffet or a not-so-fastidious small child hopping in the pool. Small cruise ship quarters also can lead to quick transmission between those sharing cabins where it would be difficult to avoid aerosolized vomit (yuuuuup). It's not just cruise ships affected; nursing homes, schools and commercial kitchens are also ideal breeding grounds for outbreaks. But I'm guessing that not that many folks are getting boozy and lax in nursing homes (and if they are, sign me up for one of those when I'm old!) Norovirus can be killed on surfaces with a little bleach and washed from your hands with soap and water.
So, for me? No thanks! The idea of taking a vacation on something dubbed a "poop cruise" doesn't sounds all that relaxing!
Thankfully involvement by the federal government and new regulations and cleaning expectations from the CDC mean that outbreak projections for 2015 are much lower than the last 5 years. Ships are now expected to allow longer times between passenger group rotations to allow for thorough cleaning even if it means taking a ship out of commission for a week (which, to me seems like short time to disinfect something that large.)
References:
172 Fall Ill After Norovirus Outbreak on Princess Cruises Ship Headed to L.A.
Widdowson, Marc-Alain, et al. "Outbreaks of acute gastroenteritis on cruise ships and on land: identification of a predominant circulating strain of norovirus—United States, 2002." Journal of Infectious Diseases 190.1 (2004): 27-36.
Zamyatkin, Dmitry F., et al. "Structural insights into mechanisms of catalysis and inhibition in Norwalk virus polymerase." Journal of Biological Chemistry 283.12 (2008): 7705-7712.
D'Souza, Doris H., et al. "Persistence of caliciviruses on environmental surfaces and their transfer to food." International journal of food microbiology 108.1 (2006): 84-91.
Chan, Martin CW, et al. "Fecal viral load and norovirus-associated gastroenteritis." Emerging infectious diseases 12.8 (2006): 1278.
Barker, J., I. B. Vipond, and S. F. Bloomfield. "Effects of cleaning and disinfection in reducing the spread of Norovirus contamination via environmental surfaces." Journal of Hospital Infection 58.1 (2004): 42-49.