Cruise Ship GI Outbreaks Are Declining, U.S. CDC Says

Scientists with the U.S. Centers for Disease Control's Vessel Sanitation Program (VSP) reported Friday that the rate of acute gastroenteritis outbreaks on cruise ships dropped sharply in 2014 to just three per thousand voyages, down from over six per thousand in 2012.

The team surveyed sanitation report data from larger cruise ships on U.S. voyages from 2008 to 2014 – a total of about 30,000 voyages and 75 million passengers.

For these 75 million passengers during the study period, only 130,000 cases of gastroenteritis were reported – a rate of less than two tenths of one percent. The rate for crew members was even lower.

And outbreaks – incidents involving many infected passengers – have shown a decreasing trend, the study found.

2014 had only 15 outbreaks, down from 17 the year before and 27 in 2012.

The rate of individual cases also came down over the study period, from 27 per 100,000 travel days in 2008 to just 22 in 2014.

Similar to patterns ashore, the rate of infections was higher in the winter months than in summer. For passengers, the average January rate was double the rate in July over the seven year study period.

Study co-author Dr. Amy Freeland told media that passengers should wash their hands thoroughly to stay safe, and that if they do become ill, they need to report it.

“Often, people don’t want to report feeling sick because they don’t want to be isolated during their vacation,” she said. “The problem with that is if there is illness onboard, crew members don’t know and they can’t step up their sanitation efforts.”

While it may seem self-evident, health experts agree that good handwashing is key to preventing the spread of norovirus. For passengers looking to stay healthy and crewmembers looking to keep their customers safe, the CDC offers specific guidelines for disease control settings. The recommended duration is 40-60 seconds.

In addition, they recommend the use of ethanol-based hand sanitizer only when hands are not visibly soiled, and for a duration of at least 20-30 seconds.