Royal Caribbean cruise officials are busy scrubbing and sanitizing a giant cruise ship after nearly 650 passengers and crew got sick with suspected norovirus this week. But it won’t be easy to get the ship spic and span for the next batch of tourists.
The norovirus is sticky and hard to kill, and it gets everywhere.
Ask the people who found the virus in light fixtures and on mantelpieces in a British hotel after an outbreak, or the flight attendants who all got sick after a single passenger threw up on a jet, or the soccer players who got sick after a teammate threw up near — not on, but near — a grocery bag.
Now translate that to a monster liner with 15 decks, four pools, six whirlpools, 15 bars, clubs and lounges — including a casino — and shops.
“Any surface that you can disinfect, you probably should,” said Benjamin Lopman, a viral disease expert at the Centers for Disease Control and Prevention.
The Explorer of the Seas ship turned back partway through a 10-day cruise from Cape Liberty, N.J., to the Caribbean island of St. Maarten after patients started getting sick, with vomiting and diarrhea — classic symptoms of norovirus. It's a big vessel, carrying 1,165 crew and 3,050 passengers who are being encouraged to stay in their cabins as much as possible to reduce the risk of infection.
"Noroviruses are perhaps the perfect human pathogens."
Cleanup means going over every square inch. Workers will spray railings, handles and elevator buttons with bleach. They’ll soak carpets in disinfectant and even clean bedside Bibles. The CDC manual for keeping cruise ships clean is 267 pages long.
“There’s one particular incident where a food handler vomited into a sink and then cleaned the sink, but subsequently used it for food preparation,” says Lopman. Thousands of people got sick in that outbreak, he says.
That’s why there are now clear guidelines on what cleaner to use, how much to use and how long to let it sit to make sure it kills all the germs. The virus is extremely infectious, easily spread, sticks to surfaces and can survive liberal sloshing with alcohol-based hand sanitizer. It takes just a few tiny particles to infect someone and people can spread it both before they start feeling sick and after they feel better. “It can spread in food, it can spread in water and even on contaminated surfaces,” says Dr. Susan Rehm, medical director of the National Foundation for Infectious Diseases.
“Noroviruses are perhaps the perfect human pathogens,” CDC’s Aron Hall writes in the Journal of Infectious Diseases.
The viruses live in just the right zone to infect people, sticking to serving spoons at buffet tables, lingering on plates even after they’ve been through the dishwasher, floating into the air when someone vomits suddenly and even settling on fresh laundry.
“Once you get it onto a surface or get it onto a food source, it is pretty easily transmitted,” said Allison Aiello, a professor of epidemiology at the University of North Carolina.
The number one disinfectant is bleach, but there are other products listed by the Environmental Protection Agency as well. The key is to use them right.
“Bleach is a good product,” Aiello added. “But you have to let it sit for the right amount of time.” Just wiping with bleach won’t do it. And some surfaces are more challenging than others — think carpets or wood, neither of which comes out looking too good after being doused with bleach.
Just a few pieces of virus can make someone sick, and people infected with norovirus will spew out millions of bits of virus.
Outbreaks have been traced to casinos, schools nursing homes and basketball tournaments. In one widely reported case, seven girls on a school soccer team got infected after another team member threw up in a bathroom near a shopping bag holding their lunch.
In 2008, several sick members of a tour group threw up on a flight from Boston to Los Angeles and ended up infecting other passengers on the flight. On another flight, staff got sick for six days after a passenger vomited. “Over the course of a week, people were still getting sick from this one contamination episode,” Lopman said.
One outbreak linked to a Kentucky middle school basketball tournament in February 2012 put two children into the hospital and made more than 240 people sick. “Three persons from three separate teams had experienced illness onset before the tournament, and one had vomited courtside in a crowded gymnasium on the first night of the tournament,” a CDC team wrote in a report on the outbreak.
And it’s not just among kids. In December 2010, 24 players or team staffers from 13 different NBA teams got sick, a different CDC team reported.
Cruise ships create a perfect storm for the virus. “Unfortunately, it is in close settings, whether it be a school, a church, a cruise ship, where people are close together where viruses like norovirus tend to spread rapidly,” Rehm said.
And if your cabinmate is sick, it’s almost impossible to avoid getting sick, too.
Royal Caribbean officials say they'll clean the vessel three times. It's due back in its home port in New jersey Wednesday, and was scheduled to go back out again Friday for a nine-day Caribbean cruise.
Several investigations have linked outbreaks with public vomiting — someone suddenly throws up, and many of the people standing nearby end up infected later. And people might not even know — for instance, in a public restroom. “If you step into the bathroom right after someone got sick it would be in the air,” said Aiello.
Lopman says one investigation at a British hotel showed just how far the viral particles could float. Researchers swabbed the hotel after an outbreak several years ago. “They found virus in the light fixtures, on door handles, on fireplace mantles,” he said. “There were surfaces around 6 feet off the ground where you found norovirus.”
But the main culprit is dirty hands. All the experts recommend thorough washing with soap and water, especially after using the restroom, and perhaps an extra dollop of hand sanitizer just to be sure. And one of the biggest battles is over food preparation and health care workers coming to work while infected.
“Someone who is sick shouldn’t be preparing food,” Lopman said. And because the virus still spreads after someone feels better, they should stay home for 24 to 48 hours after they feel better.
“Clearly it is challenging, particularly in industries where there is no paid sick leave,” Lopman notes.