Think the flu is bad? Try norovirus. One leading expert calls it “the Ferrari of the virus world” because it’s one of the most infectious viruses known to man, causing nine out of 10 episodes of viral stomach outbreaks worldwide.
Its signatures are the excretive double-whammy of diarrhea and vomiting—and violent versions of both (the norovirus symptoms are so notorious for this that scientists have created a projectile-vomiting robot to study puke-borne contagion trajectory). This makes it ultra-spreadable. Also, as science writer Carl Zimmer explains, “each gram of feces [of an infected person] contains around five billion noroviruses. (Yes, billion).” Here’s what’s worse, writes Zimmer:
Once the norovirus emerges from its miserable host, it has to survive in the environment. Noroviruses have no trouble doing so, it seems. Fine droplets released from sick people can float through the air and settle on food, on countertops, in swimming pools. They can survive freezing and heating and cleaning with many chemical disinfectants. In 2010, scientists surveyed a hospital for noroviruses and found 21 different types sitting on a single countertop. It takes fewer than 20 noroviruses slipping into a person’s mouth to start a new infection.
Impervious to both commercial dishwashers and the kind of sink-and-towel operations typical of most restaurants, it can also withstand all the Purell you can throw at it. (Fact: health care facilities that use hand sanitizers over hand-washing are six times as likely to have norovirus outbreaks.) And it’s not just counters, cutlery and other people’s hands that pose risks. You can also get norovirus from the strangest surfaces, such as a reusable shopping bag that sickened an entire tournament of soccer players.
On top of all that, there’s a new mutant strain of it which no one is vaccinated for. Called “Sydney 2012″—it’s named for the specifics of its origins—it is therefore highly contagious. Which is likely why the UK has seen 72% more cases this winter than last year, with 1.19 million Britons succumbing. It has also long since migrated to Japan, Belgium, Denmark and New Zealand. French authorities report an incidence of cases that qualify it as an epidemic.
The US, which under normal conditions sees 21 million norovirus cases a year, has been spared a good deal of this. But recent news suggests Sydney 2012 has already arrived, highlighting another peculiar feature of the norovirus: its association with cruise ships. The connection is such that it is sometimes called the “cruise ship disease.”
“Cruise ships are almost a sentinel sensing system for norovirus,” as Peter White, professor of microbiology at the University of New South Wales in Sydney, told Bloomberg. This is largely due to the close quarters of a cruise ship, which quickly become a petri dish of viral mayhem if a carrier happens to board one. This can create an “ecology” for an outbreak, despite the best intentions of the cruise lines, says Jean-Paul Rodrigue, professor of transit geography at Hofstra University.
“Health issues aboard cruise ships are of significant concern to the industry, particularly in light of a virus strain such as norovirus,” Rodrigue told Quartz by email. “Operators are usually very diligent about sanitary conditions aboard their ships… since public image is a very important factor for cruises. Still, if you excuse the pun, ‘shit happens.’”
And happen it did on the P&O’s Oriana, which toured Europe before docking in Southampton, UK, in December, smelling like vomit and carrying passengers who told the UK press they had been on “a plague ship.” The docking of the Azura in the same port the next day saw similar blowback.
And now the US is getting nervous, as three such vessels have docked in the US in the last three weeks. The Emerald Princess landed in Fort Lauderdale in late December reporting an outbreak, while the Crown Princess, which sailed from Italy to Texas, also was hit. Just this month, the Queen Mary 2 docked in Brooklyn with an outbreak of Sydney 2012. (The QM2, which does a regular route between New York and the UK, has reported norovirus outbreaks four times since 2004.)
Even as Sydney 2012′s landfall in the US begins to distract from the cruise ship chaos it’s caused, its heightened contagiousness has some suspecting that it will hurt the cruise industry. “Norovirus is going to wreak havoc in their cruise industry for the next year while this new strain gets a grip,” White told Bloomberg.
And it’s a big industry—somewhere in the range of $30 billion this year, which is a 5% increase from 2012.
Others, like Hofstra’s Rodrigue, believe the impact on cruise line revenue can easily be overestimated.
“Although stories of outbreaks on cruise ships have, of course, negative impacts on bookings, the industry has the advantage of having cruises often be booked months in advance, implying that the media attention is likely to have receded (if not altogether vanished) by the time a cruise takes place,” he says. Moreover, he notes, they can also discount to boost demand. “Thus, unless health issues on cruise ships are serious and recurrent (no indications that it is the case at this point) concerns such as the norovirus do not appear to have a notable impact on the industry,” he adds.
Moreover, demand has been increasing steadily, even through the global downturn. In the past few years, the industry has seen particularly explosive growth, with some 16.3 million passengers in 2011, a 10% increase on 2010 (pdf). That’s projected to hit 21.0 million passengers this year. Given the strong growth in demand, the constraint on growth comes much more from the supply side of the equation—from the scarcity of large ports in which to dock.
The stock prices for Royal Caribbean and Carnival, which together claim around 70% market share, would seem to bear this out. The news of the Sydney 2012 outbreaks has been accompanied by only slight hiccups in the steady climb that both of their shares have seen since July of last year.
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