Recent instances of gastrointestinal illnesses at sea have been making headlines and leaving some travelers wary of setting sail. But thankfully, you're not as likely to contract norovirus -- marked by symptoms like vomiting, nausea, diarrhea and stomach pain -- as you may think. According to the Cruise Lines International Association, seven norovirus outbreaks on cruise ships were reported in 2013. These cases affected only 1,238 of 21.3 million total passengers who sailed on CLIA-affiliated ships last year. And if an outbreak does occur, cruise ship crew members are required to report all cases to the Centers for Disease Control and Prevention before entering a U.S. port. Furthermore, CDC-mandated Outbreak Prevention and Response Plans enforce each crew member's role in thwarting the spread of norovirus via contaminated surfaces, tainted food and water, or infected passengers.
Of course, illness on cruise ships can't be fully prevented, but a few extra safety measures can make a big difference. U.S. News spoke with Assistant Deputy Chief of the CDC's Vessel Sanitation Program, Cmdr. Aimee Treffiletti to find out what cruise lines and passengers can do to ensure healthy travel at sea.
How ships prevent and control outbreaks
The CDC conducts twice-yearly sanitation inspections of cruise ships operating under the Vessel Sanitation Program's jurisdiction to determine their compliance with a long list of health and safety measures. Inspectors check nearly every inch of a ship, including all common areas, dining rooms, swimming pools and medical facilities, and score each ship on a 100-point scale. To score above the required 85 points -- and to decrease the likelihood that passengers end up with the stomach flu -- crews take the following measures:
It may seem obvious, but thorough cleaning can make a huge difference when it comes to transmitting viruses. And that's not just on surfaces in kitchens and bathrooms where norovirus tends to be most prevalent. "If they have a casino on board, a casino manager might be in charge of frequently sanitizing things like the casino chips, and changing the playing cards and sanitizing the slot machines," Treffiletti said. Areas where people have been sick are meticulously cleaned with sanitizer or disinfectant that is effective against norovirus, she added.
Often, a norovirus outbreak comes down to someone who knowingly or unknowingly brings a contagious virus on the ship. That's why one key to prevention can be ensuring that everyone on board is healthy from the get-go. Many ships have medical professionals on hand to screen passengers for signs of illness as they board, while other ships require that passengers fill out a form inquiring about vomiting or diarrhea in the 72 hours prior to sailing. If you get sick on board, you may be quarantined to your room to reduce the likelihood of spreading the virus to others. In some cases, guests may be asked to disembark due to illness; know your rights by reviewing your cruise ticket contract before you board.
File reports and notify passengers
Cruise ships must keep track of instances when passengers or crew members report multiple symptoms of the stomach flu. The ship must notify the CDC when 2 percent of the passengers on board have symptoms. Once 3 percent of people on board (on cruise ships carrying 100 or more passengers) have signs of illness, the CDC classifies the case as an outbreak. At that point, the CDC conducts an investigation to determine the cause of the pattern and to help prevent the virus from spreading further. "We go on board, we look through [the ship's] records ... and we also watch their sanitation barrier to ensure that they're following their plan -- [we're] just another set of eyes to watch," Treffiletti said of the CDC's role during an outbreak.
How passengers can avoid illness
Although the crew members work hard at prevention, their methods simply can't account for every germ. Passengers can take their health and safety into their own hands with a few key recommendations from the CDC:
Wash your hands
Proper hygiene can go a long way when it comes to protecting yourself from norovirus. "The No. 1 way to prevent the spread of a transmissible illness like norovirus is with proper and frequent hand-washing," Treffiletti emphasized. It is especially important to wash your hands before touching your mouth, after touching communal surfaces like railings or bathroom doors, and after contact with people who are sick.
Rest and hydrate
A healthy immune system is one of your best defenses against contracting viruses on board. A good amount of sleep will help your body repair and rejuvenate, so try to catch plenty of shut-eye before and during your trip. It's also important to stay hydrated: You'll flush any potential pathogens out of your system and prevent worsening symptoms due to dehydration. "You're out of your routine and maybe not drinking as much water as possible, but that's always really important," Treffiletti said.
Do your research
The CDC's Vessel Sanitation Program collects records of cruise ship norovirus outbreaks, and publishes all reports and inspection results on its website. Use the CDC's search tool to find the health records and history of any ship before you book a cruise. You can discover which ships score highest in cleanliness and which ships have had virus outbreaks in the past. U.S. News also uses ships' average CDC health ratings to calculate the Best Cruises rankings; the scores are displayed on each ship's profile. Before you choose an itinerary, consider this: You're no more likely to contract norovirus by traveling to one particular port versus another. However, Treffiletti notes that norovirus is more often found on cruises that leave during the winter months (coinciding with a seasonal increase in norovirus on U.S. shores).
Be cautious at the buffet
Cruises have a reputation for dishing out copious amounts of food, often served buffet style. But sometimes food can grow tepid if it's sitting out for too long. One trick to staying healthy at the buffet is to make sure you steer clear of anything lukewarm -- especially food items you would expect to be piping hot or very cold. Also, let crew members know if you spot someone failing to use proper utensils or otherwise contaminating the food.
Overall, the best way to stay healthy at sea is to follow the best practices for staying healthy ashore. Gastrointestinal illness is no more common on cruises than on land, Treffiletti said. "Anytime where you have a large group of people together in a lot of shared spaces ... you tend to see an increase in illnesses like norovirus."
-- Allison Michaels