Nearly 80 passengers and crew members aboard an Oceania Cruises ship became ill from a norovirus outbreak during a voyage from the United States to Canada.
Those who became ill experienced diarrhea and vomiting, which are characteristic symptoms of norovirus infection.
The cruise line and ship crew implemented several measures in response, including enhanced cleaning and disinfection procedures, in accordance with the cruise ship's outbreak prevention and response plan. Staff also collected stool specimens from sick passengers for testing and isolated those who were ill.
The ship's operators also spoke with the CDC’s Vessel Sanitation Program regarding procedures for sanitation, cleaning, and reporting protocols for ill cases.
The CDC is remotely monitoring the situation, including reviewing the ship's outbreak response and sanitation procedures.
Norovirus, commonly called the stomach flu or stomach bug, spreads easily through contaminated food, water, or surfaces, or through person-to-person contact. Most of those who become infected recover within one to three days, though they can continue spreading the virus for several days after feeling better.
The CDC requires cruise ships to report gastrointestinal illness cases when passengers and crew inform the ship's medical center about their symptoms. Medical staff evaluate whether symptoms meet the agency's case definition for acute gastroenteritis: three or more loose stools within 24 hours or more than normal for that individual, or vomiting accompanied by diarrhea, muscle ache, headache, abdominal cramps, or fever.
The agency noted that the reported cases represent the total number of people who became sick during an entire voyage and do not indicate that all affected individuals were ill at the same time.
In late September, Royal Caribbean's Serenade of the Seas experienced a similar outbreak during a 13-day voyage from San Diego.
That ship reported 94 sick passengers out of 1,874 total and four ill crew members out of 883 staff as of early October. The outbreak was reported to the Vessel Sanitation Program on Sept. 28, nine days after departure. The ship docked in Miami following the outbreak.
The high volumes of people and new environments that travelers encounter aboard large cruise ships can contribute to the spread of the illness, according to health officials. The agency encourages passengers to practice healthy cruising guidelines, including frequent handwashing and avoiding public areas when feeling sick.