At a glance
Learn about the gastrointestinal illness outbreak on Royal Caribbean ship Allure of the Seas in May 2024, including outbreak details and actions taken in response.
Outbreak details
Cruise Line: Royal Caribbean International
Cruise Ship: Allure of the Seas
Voyage Dates: May 20–May 24, 2024
Voyage number: 31795
Final case counts:
- Number of passengers who reported being ill during the voyage out of total number of passengers onboard: 121 of 6,364 (1.90%)
- Number of crew who reported being ill during the voyage out of total number of crew onboard: 3 of 2,143 (0.14%)
Predominant symptoms: diarrhea, vomiting, and abdominal cramps
Causative agent: unknown
Actions in response to the outbreak
In response to the outbreak, Royal Caribbean and the crew aboard the ship reported the following actions:
- Increased cleaning and disinfection procedures according to their outbreak prevention and response plan.
- Isolated ill passengers and crew.
A large number of cases were reported in a 12-hour period during the voyage, and many passengers reported similar symptoms and symptom onset times after travel. VSP reviewed the ship’s AGE logs and questionnaires detailing activities and meal locations for the 72 hours before that 12-hour period.
More information
Cases
Gastrointestinal illness is a commonly used term for acute gastroenteritis (AGE). Cruise ships report cases that meet our case definition for AGE. We define a reportable case of AGE as
- Three or more loose stools within a 24-hour period or what is more than normal for that person OR
- Vomiting along with one of the following symptoms: diarrhea, muscle ache, headache, abdominal cramp, or fever.
Case totals
Cases reported are totals for the entire voyage. It does not mean all people are sick at the same time, such as when they arrive or leave a port or ship.
Causative agent
Norovirus is often a cause of gastrointestinal outbreaks on cruise ships, but we don’t always know the cause of the outbreak when we begin an investigation. Finding the agent that caused an outbreak (causative agent) can take time. When an outbreak occurs, people whose symptoms met the case definition are asked to provide stool or vomitus samples. These samples are tested to determine the causative agent.
In this outbreak, outbreak notification occurred after the voyage, so samples were not available for testing.