How Cruise Lines Protect Passengers from Pests

Updated for 2023

Every year, millions of people worldwide opt for a cruise for their family vacation. And it’s no wonder why they’re so appealing, because once you step on board everything is taken care of! You have access to food, drink and entertainment any time you want it.

The floating hotel can also be attractive to several different types of pests. The confined space, stored food for thousands of people, hundreds of beds on every floor, and stops in different ports are all part of a recipe that makes a cruise ship ripe for an infestation. Pests aren’t only a nuisance, but if handled incorrectly, can also cause sickness in humans.

So, how do cruise companies keep those large ships pest-free and you safe?


Ships and Pests

For as long as there have been ships, there has been the risk of disease and pests on board. In addition to cargo and people, ships have carried rats to all parts of the world. The brown rat – which is also called the wharf rat – is believed to have been able to spread to every continent except Antarctica because of boats and ships. The black rat ended up in the British Isles more than 1600 year ago by way of boats from Rome. And the Centers for Disease Control and Prevention (CDC) says cargo ships docking in ports on the West Coast in the early 1900s are responsible for the rodents that brought the bubonic plague to the U.S.

A cargo ship that docked in the Pacific Northwest in 2019 is believed to be responsible for bringing Asian giant hornets – also known as ‘murder hornets’ – to the U.S. The hornets have threatened crops and bee farms, as well as posed a danger to humans. A shipment of stone from China in 2014 left behind spotted lantern-flies in the Northeast, which have been detrimental to oak trees and vineyards.

But it isn’t just cargo ships that have problems with pests. Cruise liners are also vulnerable to pest populations onboard. Case in point, in 2016, the Carnival Corporation had several violations on two of its ships based out of the United Kingdom. CDC inspectors found insect remains throughout the ship, a pantry with a fruit fly infestation and cockroaches in an area where food is prepped and stored.


We looked at the average vessel sanitation scores by the CDC between 2018 and 2020. Viking Cruise Lines ranked the highest with an average sanitation score of 99.2%. On the low end, Royal Caribbean had an average score of 95.4%. With all of the other cruise lines in our sample falling within that range, you can feel confident that nearly any cruise line you select will be sanitary. If you’re interested in learning more about the CDC sanitation scores for individual cruise ships, click here and search the name of the cruise ship you’re interested in.

What Type of Pests are on Cruise Ships?

Cruise lines follow pretty strict guidelines when it comes to cleanliness and pests. After all, one bad sailing where everyone gets sick or there’s a rat infestation can ruin a trip and a company. But just like at home, no matter how much cleaning and preventative measures you take, pests will still find their way onboard.

Infestations on cruise ships can happen quickly since there is limited and confined space. Bed bugs and German cockroaches tend to be the pests that end up on cruise ships most often. Since both pests avoid light, they can remain undetected more easily by hiding in dark crevices and corners.


Bed Bugs

Bed bugs are generally brought onto cruise ships in passenger luggage. They are so tiny, you generally won’t know they are there until you wake up scratching from their bites. They like to hide beneath mattresses and in dark crevices of the bed.

Cruise lines have aggressive procedures in place to detect and treat bed bugs. They generally do weekly inspections in each cabin of the bed, curtains and carpet for any signs of an infestation. Housekeeping staff members are also trained to know what to look for and be able to identify bed bugs.


Flies in general can make their way onto a ship when it ports. But once the ship sets sail again, flies are usually blown off and no longer an issue. Fruit flies, though, can pose a separate problem. They fed on rotting food and can accumulate in food storage and kitchen areas. Fruit flies carry bacteria and can give passengers food poisoning. Making sure the drains and drain lines are clean will help solve the problem, as well as properly disposing of rotting food.

German Cockroaches

Cockroaches can cause issues on cruise ships. They can get onboard many different ways, but climbing into luggage or bags when they’re being loaded on and off the ship is probably the most common. They are easier than bed bugs to spot because they are larger and can be seen scurrying when you flip the lights of a room on. The ships are equipped with special chemicals to kill them before they are able to create an infestation.

Mice and Rats

From time to time, mice and rats will make their way onto a ship while it’s docked in port. Rats and mice carry many diseases that can make humans incredibly sick. But because they’re larger pests, they can be spotted easier. And since they chew through things, the evidence of them can be found fairly easily too.

To keep these rodents from boarding, rat guards are required when a ship is docked. They are disk-shaped, metal shields that attach to the moor lines and are designed to keep a mouse or rat from climbing up the rope from the dock to the ship. Sometimes, cruise lines will also have to use traps or rat poison to get rid of a problem.

How Do Cruise Ships Keep Pests Off the Boat?

Cruise lines are required by the CDC to have a pest management plan to treat any kind of pest problem that arises on board. The plan requires cruise companies to train certain crew members in pest management, as well as schedule regular monitoring inspections at night and during the day in certain areas when there isn’t much foot traffic or activity. They must also keep a log of their monitoring program. Ships are also required to use surveillance procedures like glue traps or other devices to detect any pest activity.

Detailed logs must be kept of all preventive procedures, any pests that have been found on the ship and what was done to take care of the pest. As part of a cruise line’s pest management plan, they may also have a pest control company regularly treat the ship to prevent pest problems when they are in port.

Here are some of the main CDC preventive requirements for pest control on cruise ships:

  • All trash cans used for food waste must have tight-fitting lids and be insect and rodent resistant.
  • Rat guards of durable or non-chewable material must be used in entry points of food areas.
  • Rat guards have to be placed on any mooring line that goes ashore when a ship arrives in port, and stay on until one hour before the ship leaves.
  • Food shipments being brought onboard must be inspected for any evidence of insects, rodents or other pests.
  • All food areas must be inspected often for pests or indications of them.
  • The area of the ship where garbage is held and handled must be inspected weekly for pests.
  • All surfaces that can be touched must be regularly cleaned to control the spread and transfer of any germs.

In addition to the self-management, cruises ships undergo random, twice-a-year-inspections through the CDC’s Vessel Sanitation Program (VSP). Because cruise lines don’t know when the inspections will occur, they have to stay ready. Inspectors from the CDC will board boats that operate from U.S. ports without notice. The inspection will take between five and eight hours and is designed to ensure cleanliness, wellness and safety for all passengers.

Much like restaurant inspections, after a cruise ship inspection, each vessel is given a score. A score between 85 and 100 is considered passing. The CDC actually posts the cruise ship inspection scores on its website. Click here to view the CDC scores for cruise ships.

If a cruise ship has violations during the inspection, they are required to correct them. Some corrections can happen immediately. Others are given a certain amount of time to complete. If there are serious violations, VSP inspectors can and will keep a ship in port until they are corrected.

The United States isn’t the only country that has cruise ship inspection programs. Brazil, Canada and countries throughout the European Union also have similar programs.

The measures that cruise lines take to keep pests off their ships aren’t just beneficial to them and the people that travel on them. It helps protect ports by not introducing new pest species to the various cities they visit, which can cause new illnesses to spread among humans and cause environmental issues to the ecosystem.

How Can I Stay Healthy on a Cruise?

The thought of pests creeping and crawling around a cruise ship may make you think twice about booking your next excursion at sea. But there are some things you can do to protect yourself, your family and others.

  • If you find any pests in your cabin or in any part of the ship, you should report it to someone immediately. The pest management crew will treat the problem promptly.
  • If your family wakes up one morning and everyone has little bites and is itching, your cabin may have bed bugs. Report the problem to the housekeeping staff immediately. You’ll likely be moved to another room and be given any treatment you may need by the medical staff onboard.
  • Wash your hands often. Pests can spread germs from person to person, so it’s important that you keep your hands as clean as possible.
  • It may be difficult because there’s so much to do on a cruise, but get enough rest. That will help your immune system stay healthy and keep you from getting sick.

The threat of pests onboard ships is real, but it shouldn’t keep you from booking your next cruise. Cruise companies have stringent guidelines they follow to keep pest problems to a bare minimum. Without an active pest prevention and management plan, these companies can suffer great monetary losses. Keeping pests off the ship ensures a good time and a healthy bottom line.