Cruise Control: Reducing Your Risk for the Norwalk Virus

The Centers for Disease Control (CDC) and the International Council for Cruise Lines (ICCL) have been working together since the early 1970s to ensure your cruising experience is a safe, healthy, and enjoyable one. So, why are there disease outbreaks? Sources in the cruising industry blame it on the increased popularity of cruising. More people, more ships, more destinations, and less vessel “downtime” between trips can set the stage for a Norwalk virus outbreak. But, that does not mean your ship needs to sail without you. Here are some tips for a safe and healthy cruising adventure.

The Norwalk virus is actually quite common and is rarely a deadly or life-threatening illness. The original Norwalk virus strain was named after an outbreak of gastroenteritis in a school in Norwalk, Ohio in 1968. The gastroenteritis caused by the Norwalk virus (or Norwalk-like viruses/noroviruses) is a mild, self-limiting, but highly contagious disease characterized by nausea, vomiting, diarrhea , and abdominal pain. Muscle aches and low-grade fever may also occur. Symptoms of Norwalk virus typically develop within 1-2 days of exposure and may last from one day to one week.

Water is a common source of outbreaks of the Norwalk virus. This may include water from municipal supplies, wells, recreational lakes, swimming pools, and water stored aboard cruise ships. The Norwalk virus is transmitted by the oral-fecal route, directly from person-to-person, through ingestion of contaminated water and foods, or through contact with a surface that has been contaminated.

Shellfish and salad ingredients are the foods often implicated in Norwalk virus outbreaks. Ingestion of raw or insufficiently steamed clams and oysters poses a high risk of infection with Norwalk virus. Foods other than shellfish can be contaminated when washed in water that contains the virus or by food handlers carrying the virus.

The close living quarters of a cruise ship amplify the opportunities for transmission of Norwalk-like viruses. Because cruise ships offer such a conducive environment, the CDC and ICCL established the Vessel Sanitation Program (VSP) in the early 1970s. This means that the VSP staff can do unannounced inspections of ships. Unfortunately, despite routine cleaning and strict sanitation standards, the arrival of new, susceptible, or affected passengers every 1-2 weeks provides an environment in which the Norwalk virus can still flourish.

There are some measures you can take to reduce your risk of getting sick during your cruise.

Seek medical attention immediately. All cases of suspected Norwalk virus should be reported to the ship’s medical staff.

The most common complication of Norwalk is dehydration . Drink plenty of bottled water, clear liquids such as defizzed ginger ale or decaffeinated colas , fruit juices, or decaffeinated teas or broth made from safe drinking water.

If you become extremely sick and dehydrated, you may need a special rehydration solution. This is best obtained from the ship’s medical staff, but it may be available in a dry mix, which can be purchased in a drug store before you leave home. (Ask your doctor about this before you go). Very severe cases may require a hospital admission so that you can receive hydration and electrolytes through an IV.

Get as much rest as you can and stay calm. Gastroenteritis is an uncomfortable, but not usually serious illness, which will usually resolve itself within a few days. If you become ill onboard, you may be isolated from the rest of the passengers, or you may be asked to disembark at the next port. This is done for your own protection, as well as the protection of the other passengers on the ship. It may not be the end to your vacation that you had envisioned, but it will be in everyone's best interest. Remember, new ships sail every day. Once you are feeling better, you can be on the next one!