Be current on routine vaccines, flu, and COVID before you board, then add whatever your ports require.
The CDC says travelers should be up to date on all routine vaccines before every trip, and its destination pages list country-specific recommendations like hepatitis A. A ship concentrates people, so respiratory viruses and norovirus move fast; the CDC's Vessel Sanitation Program pushes frequent handwashing, especially after the toilet and before eating, since handrails, elevator buttons, and shared utensils spread germs. Book a travel-health review 4 to 6 weeks before departure with your itinerary.
What to do
Common questions
What vaccines do I need before a cruise?
Start with the same rule as any trip: the CDC says make sure you are up to date on all routine vaccines before every trip, which covers measles, tetanus, flu, and the rest of the standard schedule, plus current COVID vaccination. Cruises add a wrinkle: a ship is a dense, shared environment, and respiratory viruses and norovirus spread fast on board, so being current on flu and COVID shots matters more than on the average holiday. Then check the itinerary: ports in the Caribbean, Southeast Asia, or South America each carry their own vaccine recommendations, like hepatitis A for many destinations, which the CDC recommends for unvaccinated travelers going to a long list of countries. The CDC's destination pages list what is recommended per country, and a travel clinic or your GP can map your exact itinerary 4 to 6 weeks before departure. Beyond needles, ship hygiene does half the work: the CDC's Vessel Sanitation Program says wash your hands often, especially after the toilet and before eating, because handrails, elevator buttons, and shared utensils spread illness. Pack hand sanitizer with at least 60% alcohol for excursions.