In this guide
  1. Why it spreads so easily on ships
  2. The #1 habit: soap and water
  3. Other practical habits
  4. Check outbreak reports before you sail
  5. If you get sick onboard
  6. If you’re sick before you sail
  7. Sources
General information, not medical advice. This guide explains common options and official guidance. It can't account for your health, medicines or itinerary. Talk to your own doctor or pharmacist before your cruise. Medical disclaimer.

“Cruise ship virus” headlines usually mean norovirus. The CDC says more than 90% of cruise ship gastrointestinal (GI) outbreaks with a confirmed cause are norovirus (CDC Yellow Book: Cruise Ship Travel). The good news: GI illness rates on cruises fell from 32.5 to 16.9 cases per 100,000 travel days between 2006 and 2019, and there are simple habits that help.

Why it spreads so easily on ships

The CDC lists the features that make norovirus good at causing outbreaks (CDC):

  • It takes only a small amount of virus to make someone sick.
  • It spreads easily from person to person.
  • People shed the virus for a long time. It can be in stool for 2 weeks or more after feeling better (CDC: Norovirus prevention).
  • There’s no long-term immunity and no vaccine.
  • It can survive routine cleaning.

The #1 habit: soap and water

The CDC is clear: hand sanitizer does not work well against norovirus. You can use it in addition to handwashing, but not instead of it (CDC: Norovirus prevention).

Wash with soap and water for at least 20 seconds, especially:

  • Before eating (yes, every buffet trip)
  • After using the toilet or changing diapers
  • Before touching your face

On a cruise, the CDC also recommends washing hands frequently and using a sanitizer with at least 60% alcohol only when soap and water aren’t available (CDC cruise chapter).

Other practical habits

  • Avoid contact with people who are ill (CDC).
  • Follow safe food and water habits ashore.
  • Shellfish: the CDC notes quick steaming doesn’t kill norovirus. Choose well-cooked shellfish (CDC: Norovirus prevention).

Check outbreak reports before you sail

The CDC’s Vessel Sanitation Program posts GI outbreaks on ships in its jurisdiction when 3% or more of passengers or crew report symptoms. In 2026 it has listed outbreaks across several cruise lines, mostly norovirus (CDC VSP: Outbreaks on cruise ships). The CDC’s traveler checklist suggests checking this page before your trip.

If you get sick onboard

The CDC advises cruisers to call the ship’s medical center promptly, even for mild GI symptoms, and to strictly follow isolation instructions (CDC). That protects your fellow passengers and lets the medical team check for dehydration.

  • Keep sipping fluids. Oral rehydration salts are on the CDC’s travel health kit list.
  • Seek help urgently if you can’t keep fluids down, feel faint, or have blood in your stool.
  • Don’t go to the buffet or public areas while ill.

See what to do if you get sick on a cruise.

If you’re sick before you sail

The CDC says people who become ill with a communicable disease before a voyage should talk to their healthcare professional and delay travel until no longer contagious. Check cancellation terms and consider trip cancellation insurance when you book (CDC).

Sources