On July 16, 2025, the US Centers for Disease Control and Prevention (CDC) issued an official report of the 18th outbreak to happen on a cruise ship this year.

Navigator of the Seas disembarked guests on July 11, which is the same day the crew sent the report of a gastrointestinal illness outbreak to the Vessel Sanitation Program (VSP).

The 7-night round-trip voyage departed out of Los Angeles on July 4 and called on ports in Cabo, Mazatlan, and Puerto Vallarta in Mexico.

It is unclear when exactly the outbreak began, but the number of reported cases was high enough by the end of the cruise that the crew was required to report it to the VSP.

The rules state clearly that all outbreaks must be reported to the CDC when at least 3% of the crew or guests have any highly contagious symptoms.

As is pretty typical, the larger percentage of individuals on this sailing with gastrointestinal illness were the guests, not the crew.

According to the report done by the CDC, 134 of the 3,914 guests onboard the ship — which is 3.4% — experienced symptoms such as vomiting, diarrhea, and abdominal cramps.

On the other hand, only seven out of the 1,266 crew onboard (0.6%) had these same symptoms.

The outbreak may have been reported on disembarkation day, but the numbers are accumulated throughout the voyage.

That being said, the crew on Navigator of the Seas did take immediate action in response to the outbreak, beginning with increasing the cleaning and disinfecting procedures outlined in their outbreak and prevention response plan.

Beyond that, those who were ill were isolated and had specimens collected to help confirm the cause of the outbreak.

The crew also worked and consulted with the VSP to inform them of sanitation cleaning procedures and the reporting of cases of illness.

While the final verdict on the causative agent for the outbreak has yet to be confirmed, but the CDC has hinted that it is likely to be Norovirus.

There is a chance that it could remain unknown, as two other outbreaks on cruises have been unable to identify a causative agent since funding was cut to this branch of the CDC.

Despite the outbreak, Navigator of the Seas is currently wrapping up yet another 7-night voyage that has had no indications of a subsequent gastro illness outbreak.

Have Other Royal Caribbean Ships Had Outbreaks in 2025?

While there have been countless outbreaks this year, Royal Caribbean has only seen one other outbreak, and it was back in February.

Radiance of the Seas was just days into its 7-night voyage when an outbreak of gastrointestinal illness was reported to the VSP.

With 89 of the 2,164 guests onboard becoming ill, which was 4.1%, the report was again mandatory.

This outbreak caused the subsequent sailing to have delayed embarkation to allow extra time for the crew to perform a deep clean of the ship.

Like Radiance of the Seas, Navigator of the Seas also delayed embarkation for the subsequent sailing after the outbreak by several hours to allow the ship to be properly cleaned.

Read Also: 10 Reasons Why Cruise Ships Are Not Floating Petri Dishes

Guests on the July 11 voyage were informed only two days ahead of time of the expected delay for embarkation.

Despite the delay, it seems as though this sailing went on without issue and is set to disembark guests in Los Angeles on July 18, having completed the same itinerary as the cruise the week before.

However, its next several sailings will be shorter 3- and 4-night cruises with stops in Ensenada, Mexico, as well as Catalina Island.

While it may seem like there are more outbreaks than ever, cruisers should not stress too much, as sanitation protocols are improving all the time on cruise ships!