You've spent months&mdash;maybe even years&mdash;planning your big sea cruise. The last thing you want is a shipboard illness steering your dream vacation off course. But it can happen. That's why it's important to take steps to reduce your risk, both before you leave and while you're at sea.
Outbreak
You've probably read about vacation-ruining illnesses that break out on cruise ships.
While there have been outbreaks of serious illnesses such as Legionnaires' disease, COVID-19, measles and meningitis, some of the most common health problems on cruises are gastrointestinal illnesses.
Gastrointestinal illnesses may be the result of salmonella, hepatitis&nbsp;A or E.&nbsp;coli infections, but most are caused by noroviruses, reports the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=who" target="_blank">World Health Organization</a> (WHO).
Noroviruses cause inflammation of the stomach and large intestines, resulting in vomiting, diarrhea and stomach cramping. Less commonly, infection causes a low fever and headaches.
Although contagious, noroviruses generally aren't serious. Most people recover in one to three days, the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=cdc" target="_blank">Centers for Disease Control and Prevention</a> (CDC) reports.
The greatest concern&mdash;especially for older people, young children and those with weakened immune systems&mdash;is dehydration due to vomiting and diarrhea. If a person can't replace lost fluids, medical attention may be needed.
Why it happens
Most outbreaks are linked to contaminated food and water.
According to CDC, factors that contribute to the spread of disease include:
<ul>
 <li>People onboard living in a closed, crowded environment where viruses can easily spread.</li>
 <li>Passengers going on cruises even though they are ill.</li>
</ul>
How illness spreads
According to CDC, you can get infected with a norovirus by:
<ul>
 <li>Eating food or drinking liquid that's infected. </li>
 <li>Touching infected surfaces or objects and then touching your mouth, nose or eyes. </li>
 <li>Being present when someone is vomiting. </li>
 <li>Sharing food with or eating from the same utensils as an infected person. </li>
 <li>Shaking hands with an infected person and then touching your mouth, nose or eyes before you wash your hands. </li>
 <li>Caring for someone who's infected. </li>
 <li>Not washing your hands after using the bathroom or changing diapers, or not washing them before eating or preparing food. </li>
</ul>
Staying shipshape
To avoid noroviruses:
<ul>
 <li>Wash your hands after using the bathroom and before eating. Pack an alcohol-based hand sanitizer to use along with handwashing. </li>
 <li>Avoid shaking hands if there's an outbreak. </li>
 <li>Keep your hands away from your mouth. </li>
 <li>Leave the area if you see someone get sick. Report the incident to cruise staff. </li>
 <li>Get plenty of rest to keep your immune system strong. </li>
 <li>If you're sick before a cruise, call the cruise line and ask if it's possible to reschedule. </li>
</ul>
If you get sick onboard, report your illness to the ship's doctor and work to avoid behaviors that could spread the disease to others.
Before you go
Before leaving home you'll want to do a couple of things:
Research your ship. CDC operates a vessel sanitation program, which monitors outbreaks and inspects the sanitation of cruise ships. You can get reports on specific ships via the program's website at <a href="http://www.cdc.gov/nceh/vsp" target="_blank">cdc.gov/nceh/vsp</a>.
The program inspects a ship's water supply, food-handling practices, crew hygiene practices and general cleanliness, along with other factors.
Get your shots. Be sure to get the immunizations recommended for the countries you'll be visiting. You'll want to be sure your vaccinations for tetanus, measles, mumps and other diseases are up-to-date. And, depending on where you're going, you may need additional protection against diseases such as yellow fever and hepatitis&nbsp;A.
You can get information on these shots from your doctor and CDC's Travelers' Health website at <a href="http://www.cdc.gov/travel" target="_blank">cdc.gov/travel</a>. Set up an appointment for shots at least a month before your trip, as some vaccines require time to take effect. 
Reviewed 7/17/2023

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