The Centers for Disease Control and Prevention said that dozens of people on board a cruise ship now docked in California were sickened by a norovirus outbreak.
The agency’s Vessel Sanitation Program said on Wednesday that 102 passengers, out of 3,032 total, and 23 crew members, out of 1,144 total, on board the Princess Cruises’ Ruby Princess vessel reported being ill. The ship’s voyage dates were from June 12 to July 2.
The predominant symptoms reported by passengers and crew members were diarrhea and vomiting, the CDC said, identifying norovirus as the source of the outbreak, a highly contagious virus that often spreads among people in crowded conditions.
The Ruby Princess docked in San Francisco on Thursday, according to the CruiseMapper tracking service. The next destinations on the cruise itinerary include stops in Alaska and British Columbia, Canada, before it heads back to San Francisco.
The CDC said that Princess Cruises’ crew members “increased cleaning and disinfection procedures according to their outbreak prevention and response plan, collected stool specimens from gastrointestinal illness cases for testing, isolated ill passengers and crew,” and consulted with the CDC’s sanitation program. The agency added that it is remotely monitoring the outbreak situation.
With the reporting of norovirus cases on the Ruby Princess, there have been seven total outbreaks on cruise ships reported to the CDC so far in 2026.
In June, norovirus was blamed for an outbreak on the Lindblad Expeditions’ National Geographic Sea Bird cruise ship that sickened 20 of 95 passengers and crew.
Norovirus is generally considered the most common virus or bacterial infection that causes outbreaks on cruise ships. Of the seven reported outbreaks this year, five were caused by the virus and the other two by E. coli, according to the CDC.
Norovirus is often spread through food or by contact with surfaces. It is a short-lived illness for many people, but it can be dangerous for people with underlying health conditions, young children, and those aged 65 and older, health officials say.
Symptoms include sudden onset of vomiting, diarrhea, and stomach pain that can last three days, according to the CDC.
“If you have norovirus illness, you can feel extremely ill, and vomit or have diarrhea many times a day,” the agency says on its website. “This can lead to dehydration (loss of body fluids), especially in young children, older adults, and people with other illnesses.”
Most norovirus outbreaks occur when people who are already infected spread the virus directly to others, such as by sharing food or utensils.
Washing hands frequently is key to preventing a norovirus infection, especially after using the bathroom or before eating and drinking. It is best to use soap and water, scrubbing and washing for at least 20 seconds. Hand sanitizer alone doesn’t work well against norovirus, the CDC said.
Princess Cruises said in a statement to media outlets this week that crew on the Ruby Princess responded promptly and implemented “enhanced sanitation protocols across the ship.” The ship will be thoroughly cleaned and disinfected before departing on its next trip later Thursday, the company said.
Ruby Princess did not immediately respond to an Epoch Times request for comment on Friday.
