Cruise lines are battling norovirus outbreaks, affecting hundreds of passengers and crew

Cruise ships have reported the highest number of norovirus outbreaks on their ships in more than 10 years, affecting hundreds of passengers and crew members, with Royal Caribbean and Carnival Corp.’s ships among those most impacted.

Cruise lines have reported 13 separate outbreaks to the Centers of Disease Control and Prevention through the six months ending in June, up from two norovirus and two unknown outbreaks in 2022. It’s the most number of reported norovirus outbreaks on cruise ships since 2012, when there were 16.

And this year’s outbreaks represent the highest number since cruises began sailing again in summer 2021 after being suspended for more than a year due to the COVID-19 pandemic.

Seven of the outbreaks occurred on cruise lines owned by Miami-based Royal Caribbean Group and five occurred on cruise lines owned by Miami-based Carnival Corp., according to the CDC’s Vessel Sanitation Program, which requires cruise lines to report to the agency the number of passengers and crew members who say they have symptoms of gastrointestinal illness during a voyage. Celebrity, Royal Caribbean International, Holland America, Princess and P&O were among the Royal Caribbean and Carnival lines affected.

The other outbreak occurred on a ship owned by Viking Cruises.

Here’s what to know:

What is norovirus? How does it spread? How do you treat it?

Sometimes known as the “stomach flu” or “stomach bug,” noroviruses cause vomiting, diarrhea, nausea and stomach pain. However, the virus is not related to the flu, which is caused by influenza.

Most common from November to April, norovirus is the “leading cause of vomiting and diarrhea and food-borne illness in the United States,” according to the CDC. It spreads easily and can make anyone ill. The virus most often spreads in closed and crowded environments, such as hospitals, nursing homes, child care centers, school and cruise ships, according to the Mayo Clinic.

You can get norovirus in a variety of ways, such as by eating or drinking contaminated food and drinks, touching an infected surface and then touching your mouth or having direct contact with someone ill from the virus, according to the CDC.

While there is no specific treatment to treat the illness, the CDC recommends drinking lots of water or other drinks, like sports drinks, that don’t have caffeine or alcohol to help avoid dehydration. Norovirus symptoms usually last one to three days and most people recover, according to the Mayo Clinic.

When did the most recent norovirus outbreak occur on a cruise ship?

The most recent outbreak reported to the CDC occurred on Viking Neptune, a cruise ship owned by Switzerland-based Viking Cruises, during a June 6-June 20 voyage. The CDC says 110 of 838 passengers, or 13.1%, and nine of 455 crew members, or 1.98%, reported feeling ill during the voyage.

Viking Cruises said it increased cleaning and disinfection procedures, collected poop specimens from people ill with the gastrointestinal illness to send to the CDC for pathogenic identification and provided updates twice a day to officials on the number of cases on board the ship until it arrived in New York and was boarded by environmental health officers, according to the CDC’s investigation update.

When were the Carnival and Royal Caribbean cruise ship outbreaks?

Celebrity Cruises, which is owned by Royal Caribbean Group, reported norovirus outbreaks on three of its cruise ships so far this year:

Celebrity Summit

Voyage dates: May 15-May 25.

Number of people who reported being ill during voyage: 152 passengers of 2,144 (7.09%); 25 crew of 963 (2.60%).

Celebrity Equinox

Voyage dates: March 9-March 18.

Number of people who reported being ill during voyage: 122 passengers of 2,579 (4.7%); 14 crew of 1,222 (1.1%).

Celebrity Constellation

Voyage dates: March 6-March 17.

Number of people who reported being ill during voyage: 87 passengers of 2,062 (4.2%); 10 crew of 960 (1.04%)

Royal Caribbean International, which is owned by Royal Caribbean Group, reported norovirus outbreaks on four of its voyages, including two separate outbreaks on its Enchantment of the Seas:

READ MORE: What is norovirus and how do you treat it? What to know about the ‘cruise ship virus’

Enchantment of the Seas

Voyage dates: March 23-March 31 and March 11-March 23.

Number of people who reported being ill during March 23-31 voyage: 117 passengers of 2,362 (5.0%); 20 crew of 917 total (2.18%)

Number of people who reported being ill during March 11-23 voyage: 155 passengers of 2,148 (7.22%); 10 crew of 880 (1.14%).

Jewel of the Seas

Voyage dates: Jan. 28-Feb. 3.

Number of people who reported being ill during voyage: 68 passengers of 2,185 (3.11%); 1 crew of 865 (0.12%)

Brilliance of the Seas

Voyage dates: Jan. 16-Jan. 21.

Number of people who reported being ill during voyage: 70 passengers of 2,160 (3.24%); 8 crew of 838 (0.95%)

“The health and safety of our guests, crew, and communities we visit are our top priority,” Royal Caribbean said in a statement to the Herald Wednesday. “To maintain the highest levels of health onboard our ships, we implement rigorous safety and cleaning procedures, many far exceeding public health guidelines.”

Princess Cruises, which is owned by Carnival Corp. & plc, reported norovirus outbreaks on three of its ships:

Grand Princess

Voyage dates: March 31-April 28

Number of people who reported being ill during voyage: 99 passengers of 1,727 (5.73%); 32 crew of 1,089 (2.94%)

Emerald Princess

Voyage dates: March 17-April 1.

Number of people who reported being ill during voyage: 99 passengers of 2,123 (4.66%); 21 crew of 1,192 (1.76%).

Ruby Princess

Voyage dates: Feb. 26-March 5

Number of people who reported being ill during voyage: 284 passengers of 2,881 (9.9%); 34 crew of 1,159 (2.9%).

Holland America, a subsidiary of Carnival Corp. and plc, reported an outbreak on its Nieuw Amsterdam ship:

Nieuw Amsterdam

Voyage dates: May 6-May 21

Number of people who reported being ill during voyage: 246 passengers of 1,971 (12.4%); 38 crew of 826 (4.60%)

P&O Cruises, also owned by Carnival and plc, reported an outbreak on its Arcadia ship:

Arcadia

Voyage dates: Jan. 3-April 13

Number of people who reported being ill during voyage: 88 passengers of 1,752 (5.02%); 20 crew of 815 (2.45%).

Carnival did not respond to requests for comment from the Herald Wednesday.