The stomach bug caught up with Kenneth Thompson just a few days before the end of the cruise. He’d seen others getting sick and was hoping he would escape unscathed. But then his stomach started to feel queasy. Pretty soon he was vomiting every half hour. “I never had anything like this,” says the 71-year-old from Concord, S.C. “It just came out of me in streams, just gushes of it.”
Thompson was one of more than 400 passengers sickened by the norovirus on a Celebrity Cruise lines ship in mid-February. That outbreak of gastrointestinal illness is one of eight to hit cruise ships in 2010 — with four in just one week, according to the Centers for Disease Control and Prevention. The CDC has officially tied many of the outbreaks to the norovirus. Compared to 2009, when there were just 15 total outbreaks on cruise liners, the early 2010 figures may portend a very bad year.
Just a blip — or a trend?
Experts aren’t yet sure what to make of the rash of outbreaks, but they’re not ready to raise the alarm and call it an epidemic. “Four in one week — that’s not happy news,” says Dr. Claire Panosian, a clinical professor of infectious diseases at the David Geffen School of Medicine at the University of California at Los Angeles. “It could be a blip or it could be a trend. It’s too early to say.”
The only way to know whether rash of outbreaks is just a coincidence or a sign that something might have changed with the virus is to wait and see how the next few months go, says Dr. Neil Fishman, an associate professor of medicine and director of health care epidemiology and infection prevention for the University of Pennsylvania Health System. If the outbreaks continue to occur at the same rate as they have in the past few months, then there might be something to worry about, Fishman says.
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Data from the CDC show the number of norovirus outbreaks on cruise liners had been dropping over the last several years, until now. In 2008, there were 14 outbreaks; in 2007, 17; and in 2006, 32. So far, 2010 is outpacing the number of norovirus clusters recorded in 2006.
Cruise liners have begun taking extra precautions to try to stop the outbreaks. Sometimes ships delay boarding to allow crew extra time to clean between cruises. The norovirus has struck three Royal Caribbean ships this year, prompting the cruise line to enforce additional sanitizing on the ships and within the cruise terminal, according to spokesperson Cynthia Martinez.
“In these situations, there will be heightened cleaning procedures being carried out throughout the ship during the entire sailing,” she said in an e-mail.
Panosian isn’t surprised that two of the outbreaks occurred on the same ship in the same month. It’s very hard to disinfect a cruise liner, especially when you’re dealing with such a tough and virulent virus, she says.
As an example of how tough the virus is, Fishman points to an outbreak that occurred among players and spectators after a football game between the University of Pennsylvania and Cornell several decades ago. Researchers eventually determined everyone got sick from ice that was contaminated with norovirus.
Viruses like HIV and hepatitis C can’t survive being frozen and will die soon after they’re out of the body, Fishman says. So, unlike the norovirus, which can linger on surfaces, you’re unlikely to catch them from contact with a surface touched by an infected person.
That’s why the norovirus can spread so effectively, Panosian says. The virus is in both fecal matter and vomit. “You can only catch it through direct contact,” Panosian says. “But it can be in just a thin film on the finger that touches a doorknob. The next person who touches the doorknob can pick up the virus.”
Another example of the virus’s hardiness: It can sometimes survive cleaning with a 10 percent bleach solution, Fishman says, adding that experts haven’t yet figured out the best way to kill off it off.
That doesn’t mean you should give up on disinfecting your personal space, Fishman says. Hand-washing is one of the best ways to protect against the virus. Even better, use some kind of alcohol based cleanser.
Video: Mishaps trouble cruise industry Another factor contributing to the easy spread of the virus is that a person can still be infectious days after symptoms have cleared. “Even scarier,” says Fishman, “some people shed the virus and without ever having any symptoms.”
And in the close quarters of a cruise liner, you can end up with a huge human reservoir, says Panosian. The same situation tends to occur in nursing homes, Fishman says. “Minus the water slide (it's) the same kind of contained environment,” he adds.
One big problem area is the buffet tables that are so ubiquitous on cruise liners, says Panosian. She suggests people eat only hot foods and stay away from items such as sandwiches and salads. Fishman also suggests passengers stick to bottled water as an extra precaution.
The staff on Margie Ritter’s cruise ship tried to mitigate problems associated with the buffet table once the outbreak started. Passengers were served meals instead of being allowed to take from the buffet. “They didn’t even place bread bowls on the table,” says Ritter, a 51-year-old pharmacist from Myrtle Beach. “They served us individually.”
One other thing to keep in mind if you’re on a cruise: The virus has an incubation period.
Jon Blilie, 67, of Gautier, Miss., figured he’d eluded the virulent virus, but was struck by vomiting and diarrhea within a day of arriving home.
Still, Blilie says he’d sign on for another cruise. “I know that goes with the territory,” he explains. “You get that many people in such a small space. You’re going to catch something.”
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