Nearly 100 people fell ill in a norovirus outbreak aboard Royal Caribbean’s Serenade of the Seas, which docked Thursday at PortMiami in Miami, Florida.
As of Wednesday, the U.S. Centers for Disease Control and Prevention (CDC) reported 94 of the ship’s 1,874 passengers and 4 of its 883 crew with gastrointestinal symptoms, including diarrhea and vomiting. The 13-night voyage departed San Diego on September 19 and concluded October 2 in Miami, where the CDC’s Vessel Sanitation Program is monitoring the response.
The outbreak was reported Sunday to the CDC’s Vessel Sanitation Program (VSP), triggering the ship’s Outbreak Prevention and Response Plan. According to the CDC, the crew implemented enhanced cleaning and disinfection, isolated symptomatic cases, collected stool samples for analysis, consulted with VSP on protocols, and continued case reporting while en route to PortMiami. The outbreak meets CDC reporting thresholds and is among a growing number of 2025 cruise-ship gastrointestinal incidents.
Outbreak details and containment
The CDC’s threshold for public listing is generally met when 3% or more of passengers or crew report gastrointestinal illness during a voyage. On Serenade of the Seas, the passenger incidence is about 5% while crew incidence is below 1%, according to CDC figures. The ship completed its itinerary and arrived at PortMiami early Thursday, where local coverage and passenger accounts highlighted increased cleaning, removal of shared tabletop items in dining venues, and active communication from ship leadership during the final days of the cruise.
In a statement to local media, Royal Caribbean said its priority is the health and safety of guests, crew, and the communities the ship visits and noted the line’s sanitation procedures “far exceed public health guidelines,” alongside additional measures activated during outbreaks. The company’s actions described by passengers and in CDC updates include intensified surface disinfection, isolation of symptomatic cases, medical evaluation, and continuous reporting to the VSP.
Norovirus risks, symptoms, and prevention
Norovirus is a highly contagious virus that can spread through contaminated food or water, surfaces, or close contact with an infected person. Symptoms typically begin 12–48 hours after exposure and usually last 1–3 days. Most people recover without treatment, though young children, older adults, and immunocompromised individuals are at higher risk of dehydration and may require medical care, according to Mayo Clinic.
Personal prevention steps recommended by public health sources include frequent and thorough handwashing with soap for at least 20 seconds, avoiding food or beverages prepared by someone who is ill, washing fruits and vegetables, cooking seafood properly, and disinfecting high-touch surfaces. On cruise ships, immediate reporting of symptoms to medical staff, self-isolation while symptomatic, and avoiding self-serve areas can help limit spread.
The CDC’s 2025 cruise outbreak tally indicates elevated activity compared with some prior years, with multiple norovirus events confirmed across different lines and vessels. Earlier in the year, Royal Caribbean’s Navigator of the Seas reported 134 passenger cases and 7 crew cases during a July sailing, an incident also listed by the VSP. In a separate incident, the Queen Mary 2 also suffered a norovirus outbreak during a Caribbean voyage originating in England.
As Serenade of the Seas completes its Miami arrival and disembarkation, the CDC’s VSP continues remote oversight and post-voyage review of the ship’s sanitation and outbreak response measures. Final laboratory analyses of collected specimens will confirm the causative agent and inform any additional recommendations. Travelers considering upcoming cruises are advised to follow CDC and healthcare guidance on norovirus prevention and to review cruise line health protocols prior to embarkation.
Visit Cruise Critic to research and plan your future cruises, connect with other cruisers and share your passion for cruising.
Photo Credit: Darryl Brooks / Shutterstock.com
