The cruise industry had a year to forget as far as gastrointestinal outbreaks were concerned. The past year was the worst in more than a decade. Annual data released by the US Centers for Disease Control and Prevention (CDC) reported 16 outbreaks on ships last year, most of which were caused by norovirus. That is up from 14 outbreaks in 2023.
“While 2023 and 2024 both had higher numbers of cruise ship outbreaks than in years prior to the pandemic, we do not yet know if this represents a new trend,” the CDC said. “Prior to the pandemic we saw that the rates of gastrointestinal illness on cruise ships decreased during 2006-2019.”
The last month of the year was the worst, with nearly one-third of all outbreaks coming in December. It comes as demand for cruise vacations is near record levels, with corresponding high occupancy rates. Trade group Cruise Lines International Association (CLIA) has forecast about 37.1 million cruise passengers in 2025.
The CDC’s oversight of cruise outbreaks kicks in when 3% or more of the ships’ passengers or crew report sickness. Infectious disease expert Dr. William Schaffner says norovirus outbreaks vary throughout the year and tend to peak during winter months – on land and sea.
Salmonella and E.Coli Outbreaks Also Reported in 2024
Besides more than a dozen confirmed norovirus cases on ships, there was also an instance of salmonella food poisoning and E.coli in 2024. The cause of one outbreak, aboard Royal Caribbean’s Allure of the Seas in May, remains unknown.
Norovirus is widely associated as a ‘cruise ship virus’ although based on data, it makes up less than 1% of the estimated 2,500 reported norovirus outbreaks in the US.
The CDC urges cruise guests who suffer stomach bug symptoms like vomiting and diarrhea to “promptly report their illness and follow medical staff recommendations.”
The new year has got off to a bad start also, with two additional cruises reporting outbreaks. The CDC says more than 120 people have fallen ill on Holland America Line and Oceania Cruises ships.
On HAL’s Eurodam, 86 guests and eight crew have reported illness on its current cruise with the cruise line saying “cases were mostly mild.”
“We initiated enhanced sanitation protocols in conjunction with the CDC to minimize further transmission,” HAL said. On Oceania Nautica, 15 guests and 16 crew members are ill. The ship departed from Miami before Christmas. In both cases, diarrhea and vomiting are the predominant symptoms. Both cruises are scheduled to end on January 8.
