You booked your cruise months ago. The kids are excited. The bags are packed, and you're ready for the cruise holiday you've been dreaming of for so long. But you're concerned about the recent news of an apparent outbreak of a highly contagious, flu-like illness known as norovirus on Carnival Cruise Lines' largest passenger ship Liberty.

How can you protect yourself against a viral outbreak on your cruise vacation?

Norovirus, also known as viral gastroenteritis, is sometimes referred to as "24-hour flu" since it normally lasts only one or two days. According to The Centers for Disease Control and Prevention, the most common symptoms are vomiting, diarrhea and stomach cramping. While noroviruses are highly contagious, the infections are not usually serious and most patients recover from a bout with norovirus with no long-term adverse health effects.

The CDC's number one tip on preventing a viral infection while on a cruise? Wash your hands.

Most viruses are spread by contacting contaminated surfaces. One passenger covers his mouth when sneezing, and grabs hold of the handrail while walking down the steps to retire to his cabin for some rest. Now the next person who touches the rail is at increased risk of becoming infected with the virus.

Here are some tips to help reduce your risk of a viral infection during your cruise:

—Wash your hands often. Before and after eating or drinking, smoking, preparing food, using the bathroom, changing diapers, after touching high-hand contact surfaces like door knobs or railings, and after returning to your cabin.

— Avoid shaking hands during an outbreak. Your shipboard companions will understand.

— Supplement your handwashing regimen with an alcohol-based hand sanitizer. That $2 bottle of Purell just might make the difference between a cruise you'll always remember and one you wish you could forget.

A healthy immune system will also help protect against infections and enhance your body's ability to fight a virus if you do become infected. Keep your immune system strong on a cruise by following these tips:

— Get plenty of rest. Those shore excursions can take a lot out of you, make sure to recharge your immune system through adequate sleep.

— Eat right. Be sure to visit the salad and fruit bar at least once a day.

— Avoid overconsumption of alcohol and caffeine. Those drinks with the little umbrellas will indeed be delicious, but overindulging can decrease your body's ability to fight infection.

— Avoid too much sun. Overexposure to the sun is linked to decreased efficiency of the immune system.

— Exercise. The restaurant is five decks from your cabin? Take the stairs. You'll be glad you did.

— Try to reduce your stress. Too much stress can have a negative impact on your immune system. Take a yoga class or meditation class while on board. Isn't being stress-free one of the reasons you're taking a cruise anyway?

Don't let news of this outbreak worry you. There's no need to change your plans. Just make sure to pack the hand sanitizer, keep your hands clean, and focus on maintaining your immune system at full strength throughout your trip. Bon Voyage!

Dr. Manny Alvarez is the managing editor of health news at FOXNews.com, and is a regular medical contributor on the FOX News Channel. He is chairman of the Department of Obstetrics and Gynecology and Reproductive Science at Hackensack University Medical Center in New Jersey. Additionally, Alvarez is Adjunct Professor of Obstetrics and Gynecology at New York University School of Medicine in New York City.

Dr. Manny Alvarez serves as Fox News Channel's senior managing health editor. He also serves as chairman of the department of obstetrics/gynecology and reproductive science at Hackensack University Medical Center in New Jersey. Click here for more information on Dr. Manny's work with Hackensack University Medical Center. Visit AskDrManny.com for more.